From 780219dc0b80fbaf1fa031227f33ef70264e5adc Mon Sep 17 00:00:00 2001
From: Sebastião Guerra <sebastiao.luiz.guerra@gmail.com>
Date: Sun, 8 Nov 2026 08:04:33 -0300
Subject: Replace zero pointer constants in address book components
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Signed-off-by: Sebastião Guerra <sebastiao.luiz.guerra@gmail.com>
---
 kaddressbook/addresseditwidget.cpp                 |  4 +-
 kaddressbook/addresseditwidget.h                   |  4 +-
 kaddressbook/addresseeeditorbase.h                 |  2 +-
 kaddressbook/addresseeeditordialog.h               |  2 +-
 kaddressbook/addresseeeditorextension.h            |  2 +-
 kaddressbook/addresseeeditorwidget.cpp             | 14 +++----
 kaddressbook/addresseeeditorwidget.h               |  2 +-
 kaddressbook/addviewdialog.h                       |  2 +-
 kaddressbook/advancedcustomfields.h                |  2 +-
 kaddressbook/common/kabprefs.cpp                   |  2 +-
 kaddressbook/common/locationmap.cpp                |  4 +-
 kaddressbook/contacteditorwidgetmanager.cpp        |  2 +-
 kaddressbook/contacteditorwidgetmanager.h          |  2 +-
 kaddressbook/customfieldswidget.h                  |  6 +--
 kaddressbook/distributionlisteditor.cpp            |  2 +-
 kaddressbook/distributionlisteditor.h              |  2 +-
 kaddressbook/distributionlisteditor_p.h            |  4 +-
 kaddressbook/distributionlistentryview.cpp         |  4 +-
 kaddressbook/distributionlistentryview.h           |  2 +-
 kaddressbook/distributionlistpicker.cpp            |  6 +--
 kaddressbook/distributionlistpicker.h              |  2 +-
 kaddressbook/editors/cryptowidget.h                |  2 +-
 kaddressbook/editors/imeditorwidget.cpp            |  2 +-
 kaddressbook/editors/imeditorwidget.h              |  2 +-
 kaddressbook/emaileditwidget.cpp                   |  2 +-
 kaddressbook/emaileditwidget.h                     |  4 +-
 kaddressbook/extensionmanager.cpp                  |  8 ++--
 kaddressbook/extensionmanager.h                    |  2 +-
 kaddressbook/features/distributionlistngwidget.cpp |  3 +-
 kaddressbook/features/distributionlistngwidget.h   |  4 +-
 kaddressbook/features/distributionlistwidget.cpp   |  2 +-
 kaddressbook/features/resourceselection.cpp        | 10 ++---
 kaddressbook/filtereditdialog.cpp                  |  8 ++--
 kaddressbook/filtereditdialog.h                    |  4 +-
 kaddressbook/filterselectionwidget.h               |  2 +-
 kaddressbook/freebusywidget.h                      |  2 +-
 kaddressbook/geowidget.cpp                         |  2 +-
 kaddressbook/geowidget.h                           |  6 +--
 kaddressbook/imagewidget.cpp                       |  6 +--
 kaddressbook/imagewidget.h                         |  4 +-
 kaddressbook/imeditwidget.h                        |  2 +-
 kaddressbook/incsearchwidget.h                     |  2 +-
 kaddressbook/interfaces/configurewidget.h          |  2 +-
 kaddressbook/interfaces/contacteditorwidget.h      |  6 +--
 kaddressbook/interfaces/core.h                     |  2 +-
 kaddressbook/interfaces/extensionwidget.h          | 10 ++---
 kaddressbook/interfaces/xxport.cpp                 |  2 +-
 kaddressbook/interfaces/xxport.h                   |  6 +--
 kaddressbook/jumpbuttonbar.cpp                     |  2 +-
 kaddressbook/jumpbuttonbar.h                       |  2 +-
 kaddressbook/kabcore.cpp                           | 24 ++++++------
 kaddressbook/kabcore.h                             |  4 +-
 kaddressbook/kablock.cpp                           |  4 +-
 kaddressbook/kaddressbook_options.h                | 14 +++----
 kaddressbook/kaddressbookview.h                    |  6 +--
 kaddressbook/kcmconfigs/addhostdialog.h            |  2 +-
 kaddressbook/kcmconfigs/addresseewidget.cpp        |  6 +--
 kaddressbook/kcmconfigs/addresseewidget.h          |  4 +-
 kaddressbook/kcmconfigs/extensionconfigdialog.cpp  |  2 +-
 kaddressbook/kcmconfigs/extensionconfigdialog.h    |  2 +-
 kaddressbook/kcmconfigs/kabconfigwidget.h          |  2 +-
 kaddressbook/kcmconfigs/kcmkabconfig.cpp           |  4 +-
 kaddressbook/kcmconfigs/kcmkabconfig.h             |  2 +-
 kaddressbook/kcmconfigs/kcmkabcustomfields.h       |  2 +-
 kaddressbook/kcmconfigs/kcmkabldapconfig.cpp       |  4 +-
 kaddressbook/kcmconfigs/kcmkabldapconfig.h         |  2 +-
 kaddressbook/kcmconfigs/ldapoptionswidget.cpp      |  2 +-
 kaddressbook/kcmconfigs/ldapoptionswidget.h        |  2 +-
 kaddressbook/keywidget.h                           |  2 +-
 kaddressbook/ldapsearchdialog.h                    |  2 +-
 kaddressbook/main.cpp                              |  2 +-
 kaddressbook/nameeditdialog.h                      |  2 +-
 kaddressbook/phoneeditwidget.h                     |  2 +-
 kaddressbook/printing/detailledstyle.cpp           |  6 +--
 kaddressbook/printing/detailledstyle.h             |  4 +-
 kaddressbook/printing/kabentrypainter.cpp          |  2 +-
 kaddressbook/printing/kabentrypainter.h            |  2 +-
 kaddressbook/printing/mikesstyle.h                 |  2 +-
 kaddressbook/printing/printingwizard.cpp           |  8 ++--
 kaddressbook/printing/printingwizard.h             |  2 +-
 kaddressbook/printing/printprogress.h              |  2 +-
 kaddressbook/printing/printstyle.cpp               |  4 +-
 kaddressbook/printing/printstyle.h                 |  4 +-
 kaddressbook/printing/selectionpage.h              |  2 +-
 kaddressbook/printing/stylepage.h                  |  2 +-
 kaddressbook/searchmanager.h                       |  2 +-
 kaddressbook/secrecywidget.h                       |  2 +-
 kaddressbook/simpleaddresseeeditor.h               |  2 +-
 kaddressbook/soundwidget.h                         |  2 +-
 kaddressbook/thumbnailcreator/ldifvcardcreator.cpp |  4 +-
 kaddressbook/typecombo.h                           |  2 +-
 kaddressbook/viewconfigurefieldspage.h             |  4 +-
 kaddressbook/viewconfigurefilterpage.h             |  2 +-
 kaddressbook/viewconfigurewidget.h                 |  4 +-
 kaddressbook/viewmanager.cpp                       | 18 ++++-----
 kaddressbook/viewmanager.h                         |  2 +-
 kaddressbook/views/cardview.cpp                    | 44 +++++++++++-----------
 kaddressbook/views/colorlistbox.cpp                |  2 +-
 kaddressbook/views/colorlistbox.h                  |  2 +-
 kaddressbook/views/configurecardviewdialog.h       |  2 +-
 kaddressbook/views/configuretableviewdialog.h      |  2 +-
 kaddressbook/views/contactlistview.h               |  2 +-
 kaddressbook/views/kaddressbookcardview.cpp        |  2 +-
 kaddressbook/views/kaddressbookcardview.h          |  4 +-
 kaddressbook/views/kaddressbookiconview.cpp        |  2 +-
 kaddressbook/views/kaddressbookiconview.h          |  4 +-
 kaddressbook/views/kaddressbooktableview.cpp       | 14 +++----
 kaddressbook/views/kaddressbooktableview.h         |  2 +-
 kaddressbook/xxport/bookmark_xxport.h              |  2 +-
 kaddressbook/xxport/csv_xxport.h                   |  2 +-
 kaddressbook/xxport/csvimportdialog.h              |  2 +-
 kaddressbook/xxport/eudora_xxport.cpp              |  8 ++--
 kaddressbook/xxport/eudora_xxport.h                |  2 +-
 kaddressbook/xxport/kde2_xxport.h                  |  2 +-
 kaddressbook/xxport/ldif_xxport.cpp                |  2 +-
 kaddressbook/xxport/ldif_xxport.h                  |  2 +-
 kaddressbook/xxport/opera_xxport.h                 |  2 +-
 kaddressbook/xxport/pab_xxport.cpp                 |  2 +-
 kaddressbook/xxport/pab_xxport.h                   |  2 +-
 kaddressbook/xxport/vcard_xxport.cpp               |  4 +-
 kaddressbook/xxport/vcard_xxport.h                 |  2 +-
 kaddressbook/xxportmanager.h                       |  2 +-
 kaddressbook/xxportselectdialog.h                  |  2 +-
 libkpimidentities/identity.cpp                     |  4 +-
 libkpimidentities/identity.h                       |  6 +--
 libkpimidentities/identitycombo.h                  |  2 +-
 libkpimidentities/identitymanager.h                |  2 +-
 tdeabc/tdeabc2mutt/main.cpp                        | 10 ++---
 tdeabc/tdeabc2mutt/tdeabc2mutt.cpp                 |  2 +-
 tdeabc/tdeabc2mutt/tdeabc2mutt.h                   |  2 +-
 .../tdeabcdistlistupdater.cpp                      |  4 +-
 131 files changed, 259 insertions(+), 258 deletions(-)

diff --git a/kaddressbook/addresseditwidget.cpp b/kaddressbook/addresseditwidget.cpp
index 60b818208..4ee1f218d 100644
--- a/kaddressbook/addresseditwidget.cpp
+++ b/kaddressbook/addresseditwidget.cpp
@@ -238,7 +238,7 @@ AddressEditDialog::AddressEditDialog( const TDEABC::Address::List &list,
                                       const char *name )
   : KDialogBase( Plain, i18n( "street/postal", "Edit Address" ), Ok | Cancel, Ok,
                  parent, name, true, true ),
-    mPreviousAddress( 0 )
+    mPreviousAddress( nullptr )
 {
   mAddressList = list;
 
@@ -380,7 +380,7 @@ void AddressEditDialog::removeAddress()
   if ( mAddressList.count() > 0 ) {
     TDEABC::Address::List::Iterator it = mTypeCombo->selectedElement();
     if ( mPreviousAddress && mPreviousAddress->id() == (*it).id() )
-      mPreviousAddress = 0;
+      mPreviousAddress = nullptr;
 
     mAddressList.remove( it );
     mTypeCombo->updateTypes();
diff --git a/kaddressbook/addresseditwidget.h b/kaddressbook/addresseditwidget.h
index b90228e58..4f9273f31 100644
--- a/kaddressbook/addresseditwidget.h
+++ b/kaddressbook/addresseditwidget.h
@@ -55,7 +55,7 @@ class AddressEditWidget : public TQWidget
   
 
   public:
-    AddressEditWidget( TQWidget *parent, const char *name = 0 );
+    AddressEditWidget( TQWidget *parent, const char *name = nullptr );
     ~AddressEditWidget();
 
     TDEABC::Address::List addresses();
@@ -97,7 +97,7 @@ class AddressEditDialog : public KDialogBase
 
   public:
     AddressEditDialog( const TDEABC::Address::List &list, int selected,
-                       TQWidget *parent, const char *name = 0 );
+                       TQWidget *parent, const char *name = nullptr );
     ~AddressEditDialog();
 
     TDEABC::Address::List addresses();
diff --git a/kaddressbook/addresseeeditorbase.h b/kaddressbook/addresseeeditorbase.h
index 7295ae2c6..7661c0a03 100644
--- a/kaddressbook/addresseeeditorbase.h
+++ b/kaddressbook/addresseeeditorbase.h
@@ -34,7 +34,7 @@ class AddresseeEditorBase : public TQWidget
   
 
   public:
-    AddresseeEditorBase( TQWidget *parent, const char *name = 0 )
+    AddresseeEditorBase( TQWidget *parent, const char *name = nullptr )
       : TQWidget( parent, name )
     {
     }
diff --git a/kaddressbook/addresseeeditordialog.h b/kaddressbook/addresseeeditordialog.h
index b9a9d3491..53d4fef3d 100644
--- a/kaddressbook/addresseeeditordialog.h
+++ b/kaddressbook/addresseeeditordialog.h
@@ -39,7 +39,7 @@ class AddresseeEditorDialog : public KDialogBase
 
   public:
     AddresseeEditorDialog( KAB::Core *core,
-                           TQWidget *parent, const char *name = 0 );
+                           TQWidget *parent, const char *name = nullptr );
     ~AddresseeEditorDialog();
 
     void setAddressee( const TDEABC::Addressee& );
diff --git a/kaddressbook/addresseeeditorextension.h b/kaddressbook/addresseeeditorextension.h
index 5099cfbc9..4c93762fa 100644
--- a/kaddressbook/addresseeeditorextension.h
+++ b/kaddressbook/addresseeeditorextension.h
@@ -33,7 +33,7 @@ class AddresseeEditorExtension : public KAB::ExtensionWidget
   
 
   public:
-    AddresseeEditorExtension( KAB::Core *core, TQWidget *parent, const char *name = 0 );
+    AddresseeEditorExtension( KAB::Core *core, TQWidget *parent, const char *name = nullptr );
     ~AddresseeEditorExtension();
 
     /**
diff --git a/kaddressbook/addresseeeditorwidget.cpp b/kaddressbook/addresseeeditorwidget.cpp
index 584b0c74a..64650552a 100644
--- a/kaddressbook/addresseeeditorwidget.cpp
+++ b/kaddressbook/addresseeeditorwidget.cpp
@@ -74,8 +74,8 @@ AddresseeEditorWidget::AddresseeEditorWidget( TQWidget *parent, const char *name
   kdDebug(5720) << "AddresseeEditorWidget()" << endl;
 
   initGUI();
-  mCategorySelectDialog = 0;
-  mCategoryEditDialog = 0;
+  mCategorySelectDialog = nullptr;
+  mCategoryEditDialog = nullptr;
 
   // Load the empty addressee as defaults
   load();
@@ -249,7 +249,7 @@ void AddresseeEditorWidget::setupTab1()
   bar = new KSeparator( KSeparator::HLine, tab1 );
   layout->addMultiCellWidget( bar, 7, 7, 3, 6 );
 
-  TQHBoxLayout *homePageLayout = new TQHBoxLayout( 0, 11, 7 );
+  TQHBoxLayout *homePageLayout = new TQHBoxLayout( nullptr, 11, 7 );
 
   label = new TQLabel( tab1 );
   label->setPixmap( TDEGlobal::iconLoader()->loadIcon( "homepage", TDEIcon::Desktop,
@@ -265,7 +265,7 @@ void AddresseeEditorWidget::setupTab1()
   homePageLayout->addWidget( mURLEdit );
   layout->addMultiCellLayout( homePageLayout, 8, 8, 3, 6 );
 
-  TQHBoxLayout *blogLayout = new TQHBoxLayout( 0, 11, 7 );
+  TQHBoxLayout *blogLayout = new TQHBoxLayout( nullptr, 11, 7 );
   label = new TQLabel( i18n("Blog feed:"), tab1 );
   blogLayout->addWidget( label );
   mBlogEdit = new KLineEdit( tab1 );
@@ -458,7 +458,7 @@ void AddresseeEditorWidget::setupAdditionalTabs()
       pageTitle = i18n( "Misc" );
 
     ContactEditorTabPage *page = mTabPages[ pageIdentifier ];
-    if ( page == 0 ) { // tab not yet available, create one
+    if (!page) { // tab not yet available, create one
       page = new ContactEditorTabPage( mTabWidget );
       mTabPages.insert( pageIdentifier, page );
 
@@ -787,7 +787,7 @@ void AddresseeEditorWidget::nameButtonClicked()
 void AddresseeEditorWidget::selectCategories()
 {
   // Show the category dialog
-  if ( mCategorySelectDialog == 0 ) {
+  if (!mCategorySelectDialog) {
     mCategorySelectDialog = new KPIM::CategorySelectDialog( KABPrefs::instance(), this );
     connect( mCategorySelectDialog, TQ_SIGNAL( categoriesSelected( const TQStringList& ) ),
              this, TQ_SLOT( categoriesSelected( const TQStringList& ) ) );
@@ -806,7 +806,7 @@ void AddresseeEditorWidget::categoriesSelected( const TQStringList &list )
 
 void AddresseeEditorWidget::editCategories()
 {
-  if ( mCategoryEditDialog == 0 ) {
+  if (!mCategoryEditDialog) {
     mCategoryEditDialog = new KPIM::CategoryEditDialog( KABPrefs::instance(), this );
     connect( mCategoryEditDialog, TQ_SIGNAL( categoryConfigChanged() ),
              mCategorySelectDialog, TQ_SLOT( updateCategoryConfig() ) );
diff --git a/kaddressbook/addresseeeditorwidget.h b/kaddressbook/addresseeeditorwidget.h
index f2110f75a..26b747399 100644
--- a/kaddressbook/addresseeeditorwidget.h
+++ b/kaddressbook/addresseeeditorwidget.h
@@ -69,7 +69,7 @@ class AddresseeEditorWidget : public AddresseeEditorBase
   
 
   public:
-    AddresseeEditorWidget( TQWidget *parent, const char *name = 0 );
+    AddresseeEditorWidget( TQWidget *parent, const char *name = nullptr );
     ~AddresseeEditorWidget();
 
     void setAddressee( const TDEABC::Addressee& );
diff --git a/kaddressbook/addviewdialog.h b/kaddressbook/addviewdialog.h
index 15084d668..7e7e930c3 100644
--- a/kaddressbook/addviewdialog.h
+++ b/kaddressbook/addviewdialog.h
@@ -45,7 +45,7 @@ class AddViewDialog : public KDialogBase
 
   public:
     AddViewDialog( TQDict<ViewFactory> *viewFactoryDict, TQWidget *parent,
-                   const char *name = 0 );
+                   const char *name = nullptr );
     ~AddViewDialog();
 
     TQString viewName()const;
diff --git a/kaddressbook/advancedcustomfields.h b/kaddressbook/advancedcustomfields.h
index f2d2afff0..29e826c9a 100644
--- a/kaddressbook/advancedcustomfields.h
+++ b/kaddressbook/advancedcustomfields.h
@@ -43,7 +43,7 @@ class AdvancedCustomFields : public KAB::ContactEditorWidget
 
   public:
     AdvancedCustomFields( const TQString &uiFile, TDEABC::AddressBook *ab,
-                          TQWidget *parent, const char *name = 0 );
+                          TQWidget *parent, const char *name = nullptr );
 
     void loadContact( TDEABC::Addressee *addr );
     void storeContact( TDEABC::Addressee *addr );
diff --git a/kaddressbook/common/kabprefs.cpp b/kaddressbook/common/kabprefs.cpp
index c4edf5d4d..ff2e2bad3 100644
--- a/kaddressbook/common/kabprefs.cpp
+++ b/kaddressbook/common/kabprefs.cpp
@@ -27,7 +27,7 @@
 
 #include "kabprefs.h"
 
-KABPrefs *KABPrefs::mInstance = 0;
+KABPrefs *KABPrefs::mInstance = nullptr;
 static KStaticDeleter<KABPrefs> staticDeleter;
 
 KABPrefs::KABPrefs()
diff --git a/kaddressbook/common/locationmap.cpp b/kaddressbook/common/locationmap.cpp
index 8ef225cf4..08c8752ae 100644
--- a/kaddressbook/common/locationmap.cpp
+++ b/kaddressbook/common/locationmap.cpp
@@ -32,7 +32,7 @@
 #include "kabprefs.h"
 #include "locationmap.h"
 
-LocationMap *LocationMap::mSelf = 0;
+LocationMap *LocationMap::mSelf = nullptr;
 static KStaticDeleter<LocationMap> locationMapDeleter;
 
 LocationMap::LocationMap()
@@ -73,7 +73,7 @@ TQString LocationMap::createUrl( const TDEABC::Address &addr )
 
   TQString urlTemplate = KABPrefs::instance()->locationMapURL().arg( TDEGlobal::locale()->country() );
   if ( urlTemplate.isEmpty() ) {
-    KMessageBox::error( 0, i18n( "No service provider available for map lookup!\nPlease add one in the configuration dialog." ) );
+    KMessageBox::error( nullptr, i18n( "No service provider available for map lookup!\nPlease add one in the configuration dialog." ) );
     return TQString();
   }
 
diff --git a/kaddressbook/contacteditorwidgetmanager.cpp b/kaddressbook/contacteditorwidgetmanager.cpp
index 100c62681..a721d68af 100644
--- a/kaddressbook/contacteditorwidgetmanager.cpp
+++ b/kaddressbook/contacteditorwidgetmanager.cpp
@@ -38,7 +38,7 @@
 #include "contacteditorwidget.h"
 #include "contacteditorwidgetmanager.h"
 
-ContactEditorWidgetManager *ContactEditorWidgetManager::mSelf = 0;
+ContactEditorWidgetManager *ContactEditorWidgetManager::mSelf = nullptr;
 
 ContactEditorWidgetManager::ContactEditorWidgetManager()
   : TQObject( tqApp )
diff --git a/kaddressbook/contacteditorwidgetmanager.h b/kaddressbook/contacteditorwidgetmanager.h
index c4aaf5d7c..b00a11a46 100644
--- a/kaddressbook/contacteditorwidgetmanager.h
+++ b/kaddressbook/contacteditorwidgetmanager.h
@@ -70,7 +70,7 @@ class ContactEditorTabPage : public TQWidget
   
 
   public:
-    ContactEditorTabPage( TQWidget *parent, const char *name = 0 );
+    ContactEditorTabPage( TQWidget *parent, const char *name = nullptr );
 
     /**
       Adds a widget to the tab.
diff --git a/kaddressbook/customfieldswidget.h b/kaddressbook/customfieldswidget.h
index da8def76b..7642d4c9e 100644
--- a/kaddressbook/customfieldswidget.h
+++ b/kaddressbook/customfieldswidget.h
@@ -64,7 +64,7 @@ class AddFieldDialog : public KDialogBase
   
 
   public:
-    AddFieldDialog( TQWidget *parent, const char *name = 0 );
+    AddFieldDialog( TQWidget *parent, const char *name = nullptr );
 
     TQString title() const;
     TQString identifier() const;
@@ -89,7 +89,7 @@ class FieldWidget : public TQWidget
   
 
   public:
-    FieldWidget( TQWidget *parent, const char *name = 0 );
+    FieldWidget( TQWidget *parent, const char *name = nullptr );
 
     void addField( const TQString &identifier, const TQString &title,
                    const TQString &type, bool isGlobal );
@@ -124,7 +124,7 @@ class CustomFieldsWidget : public KAB::ContactEditorWidget
   
 
   public:
-    CustomFieldsWidget( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = 0 );
+    CustomFieldsWidget( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = nullptr );
 
     void loadContact( TDEABC::Addressee *addr );
     void storeContact( TDEABC::Addressee *addr );
diff --git a/kaddressbook/distributionlisteditor.cpp b/kaddressbook/distributionlisteditor.cpp
index e0711b64f..1c71f0185 100644
--- a/kaddressbook/distributionlisteditor.cpp
+++ b/kaddressbook/distributionlisteditor.cpp
@@ -154,7 +154,7 @@ KPIM::DistributionListEditor::LineEdit::LineEdit( TQWidget* parent ) : KPIM::Add
 
 
 KPIM::DistributionListEditor::EditorWidget::EditorWidget( TDEABC::AddressBook* book,  TQWidget* parent )
-    : KDialogBase( parent, /*name=*/0, /*modal=*/ true, /*caption=*/TQString(), KDialogBase::Ok|KDialogBase::Cancel ), d( new DistributionListEditor::EditorWidgetPrivate )
+    : KDialogBase( parent, /*name=*/nullptr, /*modal=*/ true, /*caption=*/TQString(), KDialogBase::Ok|KDialogBase::Cancel ), d( new DistributionListEditor::EditorWidgetPrivate )
 {
     d->addressBook = book;
     Q_ASSERT( d->addressBook );
diff --git a/kaddressbook/distributionlisteditor.h b/kaddressbook/distributionlisteditor.h
index 986b92c23..e1dc64bdb 100644
--- a/kaddressbook/distributionlisteditor.h
+++ b/kaddressbook/distributionlisteditor.h
@@ -41,7 +41,7 @@ class EditorWidget : public KDialogBase
     TQ_OBJECT
   
 public:
-    explicit EditorWidget( TDEABC::AddressBook* book, TQWidget* parent = 0 );
+    explicit EditorWidget( TDEABC::AddressBook* book, TQWidget* parent = nullptr );
     ~EditorWidget();
 
     void setDistributionList( const KPIM::DistributionList& list );
diff --git a/kaddressbook/distributionlisteditor_p.h b/kaddressbook/distributionlisteditor_p.h
index 45670f928..4f2563e11 100644
--- a/kaddressbook/distributionlisteditor_p.h
+++ b/kaddressbook/distributionlisteditor_p.h
@@ -44,7 +44,7 @@ class LineEdit : public KPIM::AddresseeLineEdit
     TQ_OBJECT
   
 public:
-    explicit LineEdit( TQWidget* parent = 0 );
+    explicit LineEdit( TQWidget* parent = nullptr );
 };
 
 
@@ -53,7 +53,7 @@ class Line : public TQWidget
     TQ_OBJECT
   
 public:
-    explicit Line( TDEABC::AddressBook* book, TQWidget* parent = 0 );
+    explicit Line( TDEABC::AddressBook* book, TQWidget* parent = nullptr );
 
     void setEntry( const KPIM::DistributionList::Entry& entry );
     KPIM::DistributionList::Entry entry() const; 
diff --git a/kaddressbook/distributionlistentryview.cpp b/kaddressbook/distributionlistentryview.cpp
index 811e5167f..e53805774 100644
--- a/kaddressbook/distributionlistentryview.cpp
+++ b/kaddressbook/distributionlistentryview.cpp
@@ -20,7 +20,7 @@
 #include <tqstringlist.h>
 #include <tqvbuttongroup.h>
 
-KAB::DistributionListEntryView::DistributionListEntryView( KAB::Core* core, TQWidget* parent ) : TQWidget( parent ), m_core( core ), m_emailGroup( 0 )
+KAB::DistributionListEntryView::DistributionListEntryView( KAB::Core* core, TQWidget* parent ) : TQWidget( parent ), m_core( core ), m_emailGroup( nullptr )
 {
     m_mainLayout = new TQVBoxLayout( this );
     m_mainLayout->setSpacing( KDialog::spacingHint() );
@@ -101,7 +101,7 @@ void KAB::DistributionListEntryView::setEntry( const KPIM::DistributionList& lis
     m_entry = entry;
 
     delete m_emailGroup;
-    m_emailGroup = 0;
+    m_emailGroup = nullptr;
 
     TQPixmap pixmap;
     pixmap.convertFromImage( m_entry.addressee.photo().data() );
diff --git a/kaddressbook/distributionlistentryview.h b/kaddressbook/distributionlistentryview.h
index 13a9a8523..6316a16f7 100644
--- a/kaddressbook/distributionlistentryview.h
+++ b/kaddressbook/distributionlistentryview.h
@@ -27,7 +27,7 @@ class DistributionListEntryView : public TQWidget
   
 
 public:
-    explicit DistributionListEntryView( KAB::Core* core, TQWidget* parent = 0 );
+    explicit DistributionListEntryView( KAB::Core* core, TQWidget* parent = nullptr );
     void setEntry( const KPIM::DistributionList& list, const KPIM::DistributionList::Entry& entry );
 
 public slots:
diff --git a/kaddressbook/distributionlistpicker.cpp b/kaddressbook/distributionlistpicker.cpp
index b7295ad81..4e41dfc05 100644
--- a/kaddressbook/distributionlistpicker.cpp
+++ b/kaddressbook/distributionlistpicker.cpp
@@ -41,7 +41,7 @@
 #include <tqregexp.h>
 #include <tqvalidator.h>
 
-KPIM::DistributionListPickerDialog::DistributionListPickerDialog( TDEABC::AddressBook* book, TQWidget* parent ) : KDialogBase( parent, 0, true, TQString(), Ok | Cancel | User1 ), m_book( book )
+KPIM::DistributionListPickerDialog::DistributionListPickerDialog( TDEABC::AddressBook* book, TQWidget* parent ) : KDialogBase( parent, nullptr, true, TQString(), Ok | Cancel | User1 ), m_book( book )
 {
     Q_ASSERT( m_book );
     setModal( true );
@@ -92,8 +92,8 @@ void KPIM::DistributionListPickerDialog::slotUser1()
     bool validName = false;
     do
     {
-        TQRegExpValidator validator( TQRegExp( "\\S+.*" ), 0 );
-        const TQString name = KInputDialog::getText( i18n( "Enter Name" ), i18n( "Enter a name for the new distribution list:" ), TQString(), 0, this, 0, &validator ).stripWhiteSpace();
+        TQRegExpValidator validator( TQRegExp( "\\S+.*" ), nullptr );
+        const TQString name = KInputDialog::getText( i18n( "Enter Name" ), i18n( "Enter a name for the new distribution list:" ), TQString(), nullptr, this, nullptr, &validator ).stripWhiteSpace();
         if ( name.isEmpty() )
             return;
 
diff --git a/kaddressbook/distributionlistpicker.h b/kaddressbook/distributionlistpicker.h
index 9a2d9f7d5..73c3cfe6c 100644
--- a/kaddressbook/distributionlistpicker.h
+++ b/kaddressbook/distributionlistpicker.h
@@ -40,7 +40,7 @@ class DistributionListPickerDialog : public KDialogBase
     TQ_OBJECT
   
 public:
-    explicit DistributionListPickerDialog( TDEABC::AddressBook* book, TQWidget* parent = 0 );
+    explicit DistributionListPickerDialog( TDEABC::AddressBook* book, TQWidget* parent = nullptr );
     TQString selectedDistributionList() const;
 
     void setLabelText( const TQString& text );
diff --git a/kaddressbook/editors/cryptowidget.h b/kaddressbook/editors/cryptowidget.h
index 101b00341..081739900 100644
--- a/kaddressbook/editors/cryptowidget.h
+++ b/kaddressbook/editors/cryptowidget.h
@@ -39,7 +39,7 @@ class CryptoWidget : public KAB::ContactEditorWidget
   
 
   public:
-    CryptoWidget( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = 0 );
+    CryptoWidget( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = nullptr );
     ~CryptoWidget();
 
     void loadContact( TDEABC::Addressee *addr );
diff --git a/kaddressbook/editors/imeditorwidget.cpp b/kaddressbook/editors/imeditorwidget.cpp
index 9db30d9cc..a33fb478e 100644
--- a/kaddressbook/editors/imeditorwidget.cpp
+++ b/kaddressbook/editors/imeditorwidget.cpp
@@ -464,7 +464,7 @@ TQString IMEditorWidget::preferred() const
 KPluginInfo * IMEditorWidget::protocolFromString( const TQString &fieldValue ) const
 {
   TQValueList<KPluginInfo *>::ConstIterator it;
-  KPluginInfo * protocol = 0;
+  KPluginInfo * protocol = nullptr;
   for ( it = mProtocols.begin(); it != mProtocols.end(); ++it ) {
     if ( (*it)->property( "X-TDE-InstantMessagingKABCField" ).toString() == fieldValue ) {
       protocol = *it;
diff --git a/kaddressbook/editors/imeditorwidget.h b/kaddressbook/editors/imeditorwidget.h
index 4f347ca02..0175d54f8 100644
--- a/kaddressbook/editors/imeditorwidget.h
+++ b/kaddressbook/editors/imeditorwidget.h
@@ -52,7 +52,7 @@ class IMEditorWidget : public KDialogBase
   
 
   public:
-    IMEditorWidget( TQWidget *parent, const TQString &preferredIM, const char *name = 0 );
+    IMEditorWidget( TQWidget *parent, const TQString &preferredIM, const char *name = nullptr );
     ~IMEditorWidget() {};
 
     void loadContact( TDEABC::Addressee *addr );
diff --git a/kaddressbook/emaileditwidget.cpp b/kaddressbook/emaileditwidget.cpp
index ead36a0c7..79557e15f 100644
--- a/kaddressbook/emaileditwidget.cpp
+++ b/kaddressbook/emaileditwidget.cpp
@@ -48,7 +48,7 @@ class EmailValidator : public TQRegExpValidator
 {
   public:
     EmailValidator()
-      : TQRegExpValidator( 0, "EmailValidator" )
+      : TQRegExpValidator( nullptr, "EmailValidator" )
     {
       TQRegExp rx( ".*@.*\\.[A-Za-z]+" );
       setRegExp( rx );
diff --git a/kaddressbook/emaileditwidget.h b/kaddressbook/emaileditwidget.h
index 3f5d0a8de..9832a9823 100644
--- a/kaddressbook/emaileditwidget.h
+++ b/kaddressbook/emaileditwidget.h
@@ -47,7 +47,7 @@ class EmailEditWidget : public TQWidget
   
 
   public:
-    EmailEditWidget( TQWidget *parent, const char *name = 0 );
+    EmailEditWidget( TQWidget *parent, const char *name = nullptr );
     ~EmailEditWidget();
 
     void setEmails( const TQStringList &list );
@@ -75,7 +75,7 @@ class EmailEditDialog : public KDialogBase
 
   public:
     EmailEditDialog( const TQStringList &list, TQWidget *parent,
-                     const char *name = 0 );
+                     const char *name = nullptr );
     ~EmailEditDialog();
 
     TQStringList emails() const;
diff --git a/kaddressbook/extensionmanager.cpp b/kaddressbook/extensionmanager.cpp
index bdc0801d2..c919714ff 100644
--- a/kaddressbook/extensionmanager.cpp
+++ b/kaddressbook/extensionmanager.cpp
@@ -40,14 +40,14 @@
 
 #include "extensionmanager.h"
 
-ExtensionData::ExtensionData() : action( 0 ), widget( 0 ), weight( 0 ), isDetailsExtension( false )
+ExtensionData::ExtensionData() : action( nullptr ), widget( nullptr ), weight( 0 ), isDetailsExtension( false )
 {
 }
 
 ExtensionManager::ExtensionManager( TQWidget* extensionBar, TQWidgetStack* detailsStack, KAB::Core *core, TQObject *parent,
                                     const char *name )
     : TQObject( parent, name ), mExtensionBar( extensionBar ), mCore( core ),
-      mMapper( 0 ), mDetailsStack( detailsStack ), mActiveDetailsWidget( 0 )
+      mMapper( nullptr ), mDetailsStack( detailsStack ), mActiveDetailsWidget( nullptr )
 {
   Q_ASSERT( mExtensionBar );
   TQVBoxLayout* layout = new TQVBoxLayout( mExtensionBar );
@@ -146,7 +146,7 @@ void ExtensionManager::setExtensionActive( const TQString& extid, bool active )
       data.widget->hide();
     }
     if ( data.isDetailsExtension ) {
-      mActiveDetailsWidget = 0;
+      mActiveDetailsWidget = nullptr;
       emit detailsWidgetDeactivated( data.widget );
     }
   }
@@ -195,7 +195,7 @@ void ExtensionManager::createExtensionWidgets()
   }
   mExtensionMap.clear();
 
-  KAB::ExtensionWidget *wdg = 0;
+  KAB::ExtensionWidget *wdg = nullptr;
 
   {
     // add addressee editor as default
diff --git a/kaddressbook/extensionmanager.h b/kaddressbook/extensionmanager.h
index a44983aca..7d4bf6f95 100644
--- a/kaddressbook/extensionmanager.h
+++ b/kaddressbook/extensionmanager.h
@@ -59,7 +59,7 @@ class ExtensionManager : public TQObject
   
 
   public:
-    ExtensionManager( TQWidget *extensionBar, TQWidgetStack *detailsStack, KAB::Core *core, TQObject *parent, const char *name = 0 );
+    ExtensionManager( TQWidget *extensionBar, TQWidgetStack *detailsStack, KAB::Core *core, TQObject *parent, const char *name = nullptr );
     ~ExtensionManager();
 
     /**
diff --git a/kaddressbook/features/distributionlistngwidget.cpp b/kaddressbook/features/distributionlistngwidget.cpp
index 181744ad7..3a98731be 100644
--- a/kaddressbook/features/distributionlistngwidget.cpp
+++ b/kaddressbook/features/distributionlistngwidget.cpp
@@ -227,7 +227,8 @@ void KAB::DistributionListNg::MainWidget::changed( const TDEABC::Addressee& dist
 
 void KAB::DistributionListNg::MainWidget::updateEntries()
 {
-    const bool hadSelection = mListBox->selectedItem() != 0;
+    const bool hadSelection =
+    mListBox->selectedItem() != nullptr;
     const TQStringList newEntries = core()->distributionListNames();
     if ( !mCurrentEntries.isEmpty() && newEntries == mCurrentEntries )
         return;
diff --git a/kaddressbook/features/distributionlistngwidget.h b/kaddressbook/features/distributionlistngwidget.h
index 75cd50ced..38e388be8 100644
--- a/kaddressbook/features/distributionlistngwidget.h
+++ b/kaddressbook/features/distributionlistngwidget.h
@@ -49,7 +49,7 @@ class ListBox : public TDEListBox
     TQ_OBJECT
   
 public:
-    ListBox( TQWidget* parent = 0 );
+    ListBox( TQWidget* parent = nullptr );
 
 signals:
 
@@ -70,7 +70,7 @@ class MainWidget : public KAB::ExtensionWidget
   
 
 public:
-    explicit MainWidget( KAB::Core *core, TQWidget *parent = 0, const char *name = 0 );
+    explicit MainWidget( KAB::Core *core, TQWidget *parent = nullptr, const char *name = nullptr );
 
     //impl
     TQString title() const;
diff --git a/kaddressbook/features/distributionlistwidget.cpp b/kaddressbook/features/distributionlistwidget.cpp
index 763248533..1f699d5a3 100644
--- a/kaddressbook/features/distributionlistwidget.cpp
+++ b/kaddressbook/features/distributionlistwidget.cpp
@@ -476,7 +476,7 @@ void DistributionListWidget::updateContactView()
   isListSelected = !dist.isEmpty();
 #else
   TDEABC::DistributionList *list = mManager->list( mNameCombo->currentText() );
-  isListSelected = list != 0;
+  isListSelected = list;
 #endif
   if ( !isListSelected ) {
     mEditListButton->setEnabled( false );
diff --git a/kaddressbook/features/resourceselection.cpp b/kaddressbook/features/resourceselection.cpp
index 4e1d6b67f..f2b33ae33 100644
--- a/kaddressbook/features/resourceselection.cpp
+++ b/kaddressbook/features/resourceselection.cpp
@@ -135,7 +135,7 @@ void ResourceItem::stateChange( bool active )
 ////
 
 ResourceSelection::ResourceSelection( KAB::Core *core, TQWidget *parent, const char *name )
-  : KAB::ExtensionWidget( core, parent, name ), mManager( 0 )
+  : KAB::ExtensionWidget( core, parent, name ), mManager( nullptr )
 {
   initGUI();
 
@@ -264,7 +264,7 @@ void ResourceSelection::add()
     currentChanged(mListView->currentItem() );
   } else {
     delete resource;
-    resource = 0;
+    resource = nullptr;
   }
 }
 
@@ -367,7 +367,7 @@ void ResourceSelection::updateView()
     ResourceItem *item = new ResourceItem( mListView, *it );
     KPIM::ResourceABC* resource = dynamic_cast<KPIM::ResourceABC *>( *it );
     if ( resource ) {
-      disconnect( resource, 0, this, 0 );
+      disconnect( resource, nullptr, this, nullptr );
       connect( resource, TQ_SIGNAL( signalSubresourceAdded( KPIM::ResourceABC *,
                                                          const TQString &, const TQString & ) ),
                TQ_SLOT( slotSubresourceAdded( KPIM::ResourceABC *,
@@ -444,7 +444,7 @@ void ResourceSelection::slotSubresourceChanged( KPIM::ResourceABC* resource,
   kdDebug(5720) << resource->resourceName() << subResource << endl;
 
   ResourceItem *item = findSubResourceItem( resource, subResource );
-  if ( item == 0 ) {
+  if (!item) {
       kdWarning(5720) << "Changed before it was added?" << endl;
       slotSubresourceAdded( resource, type, subResource );
       return;
@@ -479,7 +479,7 @@ ResourceItem* ResourceSelection::findSubResourceItem( KPIM::ResourceABC *resourc
         }
     }
 
-    return 0;
+    return nullptr;
 }
 
 void ResourceSelection::initGUI()
diff --git a/kaddressbook/filtereditdialog.cpp b/kaddressbook/filtereditdialog.cpp
index 5873ae181..11404f05b 100644
--- a/kaddressbook/filtereditdialog.cpp
+++ b/kaddressbook/filtereditdialog.cpp
@@ -70,7 +70,7 @@ void FilterEditDialog::setFilter( const Filter &filter )
 
   TQStringList categories = filter.categories();
   TQListViewItem *item = mCategoriesView->firstChild();
-  while ( item != 0 ) {
+  while (item) {
     if ( categories.contains( item->text( 0 ) ) ) {
       TQCheckListItem *checkItem = static_cast<TQCheckListItem*>( item );
       checkItem->setOn( true );
@@ -93,7 +93,7 @@ Filter FilterEditDialog::filter()
 
   TQStringList categories;
   TQListViewItem *item = mCategoriesView->firstChild();
-  while ( item != 0 ) {
+  while (item) {
     TQCheckListItem *checkItem = static_cast<TQCheckListItem*>( item );
     if ( checkItem->isOn() )
       categories.append( item->text( 0 ) );
@@ -228,7 +228,7 @@ void FilterDialog::remove()
 {
   mFilterList.remove( mFilterList.at( mFilterListBox->currentItem() ) );
 
-  selectionChanged( 0 );
+  selectionChanged( nullptr );
 
   refresh();
 }
@@ -244,7 +244,7 @@ void FilterDialog::refresh()
 
 void FilterDialog::selectionChanged( TQListBoxItem *item )
 {
-  bool state = ( item != 0 );
+  bool state = item != nullptr;
 
   mEditButton->setEnabled( state );
   mRemoveButton->setEnabled( state );
diff --git a/kaddressbook/filtereditdialog.h b/kaddressbook/filtereditdialog.h
index 39698ad7e..5b2b21c69 100644
--- a/kaddressbook/filtereditdialog.h
+++ b/kaddressbook/filtereditdialog.h
@@ -43,7 +43,7 @@ class FilterDialog : public KDialogBase
   
 
   public:
-    FilterDialog( TQWidget *parent, const char *name = 0 );
+    FilterDialog( TQWidget *parent, const char *name = nullptr );
     ~FilterDialog();
 
     void setFilters( const Filter::List &list );
@@ -73,7 +73,7 @@ class FilterEditDialog : public KDialogBase
     TQ_OBJECT
   
   public:
-    FilterEditDialog( TQWidget *parent, const char *name = 0 );
+    FilterEditDialog( TQWidget *parent, const char *name = nullptr );
     ~FilterEditDialog();
 
     void setFilter( const Filter &filter );
diff --git a/kaddressbook/filterselectionwidget.h b/kaddressbook/filterselectionwidget.h
index f0ebba2a9..54a9726bd 100644
--- a/kaddressbook/filterselectionwidget.h
+++ b/kaddressbook/filterselectionwidget.h
@@ -39,7 +39,7 @@ class FilterSelectionWidget : public TQHBox
   
 
   public:
-    FilterSelectionWidget( TQWidget *parent, const char *name = 0 );
+    FilterSelectionWidget( TQWidget *parent, const char *name = nullptr );
     ~FilterSelectionWidget();
 
     void setItems( const TQStringList &names );
diff --git a/kaddressbook/freebusywidget.h b/kaddressbook/freebusywidget.h
index 1098b9af9..6bbc31adf 100644
--- a/kaddressbook/freebusywidget.h
+++ b/kaddressbook/freebusywidget.h
@@ -34,7 +34,7 @@ class FreeBusyWidget : public KAB::ContactEditorWidget
   
 
   public:
-    FreeBusyWidget( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = 0 );
+    FreeBusyWidget( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = nullptr );
     ~FreeBusyWidget();
 
     void loadContact( TDEABC::Addressee *addr );
diff --git a/kaddressbook/geowidget.cpp b/kaddressbook/geowidget.cpp
index e1bd2b10c..bcbe9ad04 100644
--- a/kaddressbook/geowidget.cpp
+++ b/kaddressbook/geowidget.cpp
@@ -47,7 +47,7 @@
 GeoWidget::GeoWidget( TDEABC::AddressBook *ab, TQWidget *parent, const char *name )
   : KAB::ContactEditorWidget( ab, parent, name ), mReadOnly( false )
 {
-  TQLabel *label = 0;
+  TQLabel *label = nullptr;
 
   TQGridLayout *topLayout = new TQGridLayout( this, 4, 3 );
   topLayout->setMargin( KDialog::marginHint() );
diff --git a/kaddressbook/geowidget.h b/kaddressbook/geowidget.h
index 62742bb63..66cf083fb 100644
--- a/kaddressbook/geowidget.h
+++ b/kaddressbook/geowidget.h
@@ -54,7 +54,7 @@ class GeoWidget : public KAB::ContactEditorWidget
   
 
   public:
-    GeoWidget( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = 0 );
+    GeoWidget( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = nullptr );
     ~GeoWidget();
 
     void loadContact( TDEABC::Addressee *addr );
@@ -81,7 +81,7 @@ class GeoDialog : public KDialogBase
   
 
   public:
-    GeoDialog( TQWidget *parent, const char *name = 0 );
+    GeoDialog( TQWidget *parent, const char *name = nullptr );
     ~GeoDialog();
 
     void setLatitude( double latitude );
@@ -127,7 +127,7 @@ class GeoMapWidget : public TQWidget
   
 
   public:
-    GeoMapWidget( TQWidget *parent, const char *name = 0 );
+    GeoMapWidget( TQWidget *parent, const char *name = nullptr );
     ~GeoMapWidget();
 
     void setLatitude( double latitude );
diff --git a/kaddressbook/imagewidget.cpp b/kaddressbook/imagewidget.cpp
index 2ff5bdef4..1076ab099 100644
--- a/kaddressbook/imagewidget.cpp
+++ b/kaddressbook/imagewidget.cpp
@@ -48,7 +48,7 @@
 #include "imagewidget.h"
 
 ImageLoader::ImageLoader( TQWidget *parent )
-  : TQObject( 0, "ImageLoader" ), mParent( parent )
+  : TQObject( nullptr, "ImageLoader" ), mParent( parent )
 {
 }
 
@@ -105,7 +105,7 @@ TDEABC::Picture ImageLoader::loadPicture( const KURL &url, bool *ok )
 
 ImageButton::ImageButton( const TQString &title, TQWidget *parent )
   : TQPushButton( title, parent ),
-    mReadOnly( false ), mImageLoader( 0 )
+    mReadOnly( false ), mImageLoader( nullptr )
 {
   setAcceptDrops( true );
 
@@ -270,7 +270,7 @@ ImageBaseWidget::ImageBaseWidget( const TQString &title,
 ImageBaseWidget::~ImageBaseWidget()
 {
   delete mImageLoader;
-  mImageLoader = 0;
+  mImageLoader = nullptr;
 }
 
 void ImageBaseWidget::setReadOnly( bool readOnly )
diff --git a/kaddressbook/imagewidget.h b/kaddressbook/imagewidget.h
index 1cfcdd2df..50563d466 100644
--- a/kaddressbook/imagewidget.h
+++ b/kaddressbook/imagewidget.h
@@ -101,7 +101,7 @@ class ImageBaseWidget : public TQWidget
   
 
   public:
-    ImageBaseWidget( const TQString &title, TQWidget *parent, const char *name = 0 );
+    ImageBaseWidget( const TQString &title, TQWidget *parent, const char *name = nullptr );
     ~ImageBaseWidget();
 
     /**
@@ -129,7 +129,7 @@ class ImageBaseWidget : public TQWidget
 class ImageWidget : public KAB::ContactEditorWidget
 {
   public:
-    ImageWidget( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = 0 );
+    ImageWidget( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = nullptr );
 
     void loadContact( TDEABC::Addressee *addr );
     void storeContact( TDEABC::Addressee *addr );
diff --git a/kaddressbook/imeditwidget.h b/kaddressbook/imeditwidget.h
index 571ca64d8..8444f71b5 100644
--- a/kaddressbook/imeditwidget.h
+++ b/kaddressbook/imeditwidget.h
@@ -47,7 +47,7 @@ class IMEditWidget : public TQWidget
   
 
   public:
-    IMEditWidget(TQWidget *parent, TDEABC::Addressee &addr, const char *name = 0 );
+    IMEditWidget(TQWidget *parent, TDEABC::Addressee &addr, const char *name = nullptr );
     ~IMEditWidget();
 
     void setIMs( const TQStringList &list );
diff --git a/kaddressbook/incsearchwidget.h b/kaddressbook/incsearchwidget.h
index 6f3c666db..10090d2be 100644
--- a/kaddressbook/incsearchwidget.h
+++ b/kaddressbook/incsearchwidget.h
@@ -38,7 +38,7 @@ class IncSearchWidget : public TQWidget
   
 
   public:
-    IncSearchWidget( TQWidget *parent, const char *name = 0 );
+    IncSearchWidget( TQWidget *parent, const char *name = nullptr );
     ~IncSearchWidget();
 
     TDEABC::Field::List currentFields() const;
diff --git a/kaddressbook/interfaces/configurewidget.h b/kaddressbook/interfaces/configurewidget.h
index bd6dc6baf..4963a48f2 100644
--- a/kaddressbook/interfaces/configurewidget.h
+++ b/kaddressbook/interfaces/configurewidget.h
@@ -38,7 +38,7 @@ namespace KAB {
 class TDE_EXPORT ConfigureWidget : public TQWidget
 {
   public:
-    ConfigureWidget( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = 0 );
+    ConfigureWidget( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = nullptr );
     ~ConfigureWidget();
 
     /**
diff --git a/kaddressbook/interfaces/contacteditorwidget.h b/kaddressbook/interfaces/contacteditorwidget.h
index c9dc07b13..041e9099c 100644
--- a/kaddressbook/interfaces/contacteditorwidget.h
+++ b/kaddressbook/interfaces/contacteditorwidget.h
@@ -42,7 +42,7 @@ class TDE_EXPORT ContactEditorWidget : public TQWidget
   public:
     typedef TQValueList<ContactEditorWidget*> List;
 
-    ContactEditorWidget( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = 0 );
+    ContactEditorWidget( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = nullptr );
     ~ContactEditorWidget();
 
     /**
@@ -118,7 +118,7 @@ class ContactEditorWidgetFactory : public KLibFactory
 {
   public:
     virtual ContactEditorWidget *createWidget( TDEABC::AddressBook *ab, TQWidget *parent,
-                                               const char *name = 0 ) = 0;
+                                               const char *name = nullptr ) = 0;
 
     /**
       Returns the i18ned title of this tab page.
@@ -135,7 +135,7 @@ class ContactEditorWidgetFactory : public KLibFactory
     virtual TQObject* createObject( TQObject*, const char*, const char*,
                                    const TQStringList & )
     {
-      return 0;
+      return nullptr;
     }
 };
 
diff --git a/kaddressbook/interfaces/core.h b/kaddressbook/interfaces/core.h
index 57a84d702..e73f85a5f 100644
--- a/kaddressbook/interfaces/core.h
+++ b/kaddressbook/interfaces/core.h
@@ -58,7 +58,7 @@ class TDE_EXPORT Core : public TQObject
   
 
   public:
-    Core( KXMLGUIClient *client, TQObject *parent, const char *name = 0 );
+    Core( KXMLGUIClient *client, TQObject *parent, const char *name = nullptr );
 
     /**
       Returns a pointer to the StdAddressBook of the application.
diff --git a/kaddressbook/interfaces/extensionwidget.h b/kaddressbook/interfaces/extensionwidget.h
index 43c29898b..82ca7beb3 100644
--- a/kaddressbook/interfaces/extensionwidget.h
+++ b/kaddressbook/interfaces/extensionwidget.h
@@ -42,7 +42,7 @@ class TDE_EXPORT ExtensionWidget : public TQWidget
   
 
   public:
-    ExtensionWidget( Core *core, TQWidget *parent, const char *name = 0 );
+    ExtensionWidget( Core *core, TQWidget *parent, const char *name = nullptr );
     ~ExtensionWidget();
 
     /**
@@ -93,11 +93,11 @@ class ExtensionFactory : public KLibFactory
 {
   public:
     virtual ExtensionWidget *extension( KAB::Core *core, TQWidget *parent,
-                                        const char *name = 0 ) = 0;
+                                        const char *name = nullptr ) = 0;
 
-    virtual ConfigureWidget *configureWidget( TQWidget*, const char* = 0 )
+    virtual ConfigureWidget *configureWidget( TQWidget*, const char* = nullptr )
     {
-      return 0;
+      return nullptr;
     }
 
     virtual bool configureWidgetAvailable() { return false; }
@@ -112,7 +112,7 @@ class ExtensionFactory : public KLibFactory
     virtual TQObject* createObject( TQObject*, const char*, const char*,
                                    const TQStringList & )
     {
-      return 0;
+      return nullptr;
     }
 };
 
diff --git a/kaddressbook/interfaces/xxport.cpp b/kaddressbook/interfaces/xxport.cpp
index 19ab9b999..25e557705 100644
--- a/kaddressbook/interfaces/xxport.cpp
+++ b/kaddressbook/interfaces/xxport.cpp
@@ -59,7 +59,7 @@ XXPort::XXPort( TDEABC::AddressBook *ab, TQWidget *parent,
 XXPort::~XXPort()
 {
   delete d;
-  d = 0;
+  d = nullptr;
 }
 
 bool XXPort::exportContacts( const TDEABC::AddresseeList&, const TQString& )
diff --git a/kaddressbook/interfaces/xxport.h b/kaddressbook/interfaces/xxport.h
index 8f4d306e8..6a96dfc28 100644
--- a/kaddressbook/interfaces/xxport.h
+++ b/kaddressbook/interfaces/xxport.h
@@ -71,7 +71,7 @@ class TDE_EXPORT XXPort : public TQObject, virtual public KXMLGUIClient
   
 
   public:
-    XXPort( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = 0 );
+    XXPort( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = nullptr );
     ~XXPort();
 
     /**
@@ -164,13 +164,13 @@ class XXPortFactory : public KLibFactory
 {
   public:
     virtual XXPort *xxportObject( TDEABC::AddressBook *ab, TQWidget *parent,
-                                  const char *name = 0 ) = 0;
+                                  const char *name = nullptr ) = 0;
 
   protected:
     virtual TQObject* createObject( TQObject*, const char*, const char*,
                                    const TQStringList & )
     {
-      return 0;
+      return nullptr;
     }
 };
 
diff --git a/kaddressbook/jumpbuttonbar.cpp b/kaddressbook/jumpbuttonbar.cpp
index f58546cac..67c30087d 100644
--- a/kaddressbook/jumpbuttonbar.cpp
+++ b/kaddressbook/jumpbuttonbar.cpp
@@ -110,7 +110,7 @@ void JumpButtonBar::updateButtons()
   TDEABC::AddressBook *ab = mCore->addressBook();
   TDEABC::AddressBook::Iterator it;
   for ( it = ab->begin(); it != ab->end(); ++it ) {
-    TDEABC::Field *field = 0;
+    TDEABC::Field *field = nullptr;
     field = mCore->currentSortField();
     if ( field ) {
       setEnabled( true );
diff --git a/kaddressbook/jumpbuttonbar.h b/kaddressbook/jumpbuttonbar.h
index 4be2fafc3..4d9b3b399 100644
--- a/kaddressbook/jumpbuttonbar.h
+++ b/kaddressbook/jumpbuttonbar.h
@@ -50,7 +50,7 @@ class JumpButtonBar : public TQWidget
   
 
   public:
-    JumpButtonBar( KAB::Core *core, TQWidget *parent, const char *name = 0 );
+    JumpButtonBar( KAB::Core *core, TQWidget *parent, const char *name = nullptr );
     ~JumpButtonBar();
 
   public slots:
diff --git a/kaddressbook/kabcore.cpp b/kaddressbook/kabcore.cpp
index 68ce3faa8..76f2bbbff 100644
--- a/kaddressbook/kabcore.cpp
+++ b/kaddressbook/kabcore.cpp
@@ -93,9 +93,9 @@
 
 KABCore::KABCore( KXMLGUIClient *client, bool readWrite, TQWidget *parent,
                   const TQString &file, const char *name )
-  : KAB::Core( client, parent, name ), mStatusBar( 0 ), mViewManager( 0 ),
-    mExtensionManager( 0 ), mJumpButtonBar( 0 ), mCategorySelectDialog( 0 ),
-    mCategoryEditDialog( 0 ), mLdapSearchDialog( 0 ), mReadWrite( readWrite ),
+  : KAB::Core( client, parent, name ), mStatusBar( nullptr ), mViewManager( nullptr ),
+    mExtensionManager( nullptr ), mJumpButtonBar( nullptr ), mCategorySelectDialog( nullptr ),
+    mCategoryEditDialog( nullptr ), mLdapSearchDialog( nullptr ), mReadWrite( readWrite ),
     mModified( false )
 {
   mWidget = new TQWidget( parent, name );
@@ -194,9 +194,9 @@ KABCore::~KABCore()
 {
   mAddressBook->disconnect();
 
-  mAddressBook = 0;
+  mAddressBook = nullptr;
   TDEABC::StdAddressBook::close();
-  mKIMProxy = 0;
+  mKIMProxy = nullptr;
 }
 
 void KABCore::restoreSettings()
@@ -272,7 +272,7 @@ TDEABC::Resource *KABCore::requestResource( TQWidget *parent )
   TQPtrList<KRES::Resource> kresResources;
   TQPtrListIterator<TDEABC::Resource> resIt( tdeabcResources );
   TDEABC::Resource *resource;
-  while ( ( resource = resIt.current() ) != 0 ) {
+  while ((resource = resIt.current()) != nullptr) {
     ++resIt;
     bool writable = false;
     if ( resource->inherits( "KPIM::ResourceABC" ) ) {
@@ -684,7 +684,7 @@ bool KABCore::modified() const
 
 void KABCore::contactModified( const TDEABC::Addressee &addr )
 {
-  Command *command = 0;
+  Command *command = nullptr;
 
   // check if it exists already
   TDEABC::Addressee origAddr = mAddressBook->findByUid( addr.uid() );
@@ -729,7 +729,7 @@ void KABCore::newDistributionList()
 
 void KABCore::newContact()
 {
-  AddresseeEditorDialog *dialog = 0;
+  AddresseeEditorDialog *dialog = nullptr;
 
   TDEABC::Resource* resource = requestResource( mWidget );
 
@@ -940,7 +940,7 @@ void KABCore::extensionModified( const TDEABC::Addressee::List &list )
     TDEABC::Addressee::List::ConstIterator it;
     const TDEABC::Addressee::List::ConstIterator endIt( list.end() );
     for ( it = list.begin(); it != endIt; ++it ) {
-      Command *command = 0;
+      Command *command = nullptr;
 
       // check if it exists already
       TDEABC::Addressee origAddr = mAddressBook->findByUid( (*it).uid() );
@@ -1382,7 +1382,7 @@ void KABCore::initActions()
   mActionJumpBar->setCheckedState( i18n( "Hide Jump Bar") );
   connect( mActionJumpBar, TQ_SIGNAL( toggled( bool ) ), TQ_SLOT( setJumpButtonBarVisible( bool ) ) );
 
-  mActionDetails = new TDEToggleAction( i18n( "Show Details" ), 0, 0,
+  mActionDetails = new TDEToggleAction( i18n( "Show Details" ), nullptr, 0,
                                       actionCollection(), "options_show_details" );
   mActionDetails->setWhatsThis( i18n( "Toggle whether the details page shall be visible." ) );
   mActionDetails->setCheckedState( i18n( "Hide Details") );
@@ -1480,7 +1480,7 @@ TQStringList KABCore::allCategories() const
 void KABCore::setCategories()
 {
   // Show the category dialog
-  if ( mCategorySelectDialog == 0 ) {
+  if (!mCategorySelectDialog) {
     mCategorySelectDialog = new KPIM::CategorySelectDialog( KABPrefs::instance(), mWidget );
     connect( mCategorySelectDialog, TQ_SIGNAL( categoriesSelected( const TQStringList& ) ),
              TQ_SLOT( categoriesSelected( const TQStringList& ) ) );
@@ -1527,7 +1527,7 @@ void KABCore::categoriesSelected( const TQStringList &categories )
 
 void KABCore::editCategories()
 {
-  if ( mCategoryEditDialog == 0 ) {
+  if (!mCategoryEditDialog) {
     mCategoryEditDialog = new KPIM::CategoryEditDialog( KABPrefs::instance(), mWidget );
     connect( mCategoryEditDialog, TQ_SIGNAL( categoryConfigChanged() ),
              mCategorySelectDialog, TQ_SLOT( updateCategoryConfig() ) );
diff --git a/kaddressbook/kabcore.h b/kaddressbook/kabcore.h
index 0f8184701..7bb151aac 100644
--- a/kaddressbook/kabcore.h
+++ b/kaddressbook/kabcore.h
@@ -87,7 +87,7 @@ class TDE_EXPORT KABCore : public KAB::Core
 
   public:
     KABCore( KXMLGUIClient *client, bool readWrite, TQWidget *parent,
-             const TQString &file = TQString(), const char *name = 0 );
+             const TQString &file = TQString(), const char *name = nullptr );
     ~KABCore();
 
     /**
@@ -436,7 +436,7 @@ class TDE_EXPORT KABCore : public KAB::Core
     TQStringList allCategories() const;
 
     AddresseeEditorDialog *createAddresseeEditorDialog( TQWidget *parent,
-                                                        const char *name = 0 );
+                                                        const char *name = nullptr );
 
     TQWidget *mWidget;
     TDEABC::AddressBook *mAddressBook;
diff --git a/kaddressbook/kablock.cpp b/kaddressbook/kablock.cpp
index 58fa19f14..0b23ac5b3 100644
--- a/kaddressbook/kablock.cpp
+++ b/kaddressbook/kablock.cpp
@@ -40,7 +40,7 @@ class AddressBookWrapper : public TDEABC::AddressBook
     }
 };
 
-KABLock *KABLock::mSelf = 0;
+KABLock *KABLock::mSelf = nullptr;
 
 static KStaticDeleter<KABLock> kabLockDeleter;
 
@@ -86,7 +86,7 @@ bool KABLock::lock( TDEABC::Resource *resource )
 bool KABLock::unlock( TDEABC::Resource *resource )
 {
   AddressBookWrapper *wrapper = static_cast<AddressBookWrapper*>( mAddressBook );
-  if ( resource == 0 )
+  if (!resource)
     resource = wrapper->getStandardResource();
 
   if ( mLocks.find( resource ) == mLocks.end() ) { // hmm, not good...
diff --git a/kaddressbook/kaddressbook_options.h b/kaddressbook/kaddressbook_options.h
index 9ed4146e5..f8693ac37 100644
--- a/kaddressbook/kaddressbook_options.h
+++ b/kaddressbook/kaddressbook_options.h
@@ -29,13 +29,13 @@
 
 static TDECmdLineOptions kaddressbook_options[] =
 {
-  { "a", 0 , 0 },
-  { "addr <email>", I18N_NOOP( "Shows contact editor with given email address" ), 0 },
-  { "uid <uid>", I18N_NOOP( "Shows contact editor with given uid" ), 0 },
-  { "editor-only", I18N_NOOP( "Launches in editor only mode" ), 0 },
-  { "new-contact", I18N_NOOP( "Launches editor for the new contact" ), 0 },
-  { "document <file>", I18N_NOOP( "Work on given file" ), 0 },
-  { "+[URL]", I18N_NOOP( "Import the given vCard" ), 0 },
+  { "a", nullptr , nullptr },
+  { "addr <email>", I18N_NOOP( "Shows contact editor with given email address" ), nullptr },
+  { "uid <uid>", I18N_NOOP( "Shows contact editor with given uid" ), nullptr },
+  { "editor-only", I18N_NOOP( "Launches in editor only mode" ), nullptr },
+  { "new-contact", I18N_NOOP( "Launches editor for the new contact" ), nullptr },
+  { "document <file>", I18N_NOOP( "Work on given file" ), nullptr },
+  { "+[URL]", I18N_NOOP( "Import the given vCard" ), nullptr },
   TDECmdLineLastOption
 };
 
diff --git a/kaddressbook/kaddressbookview.h b/kaddressbook/kaddressbookview.h
index 3ba9ebdc2..77a8aab82 100644
--- a/kaddressbook/kaddressbookview.h
+++ b/kaddressbook/kaddressbookview.h
@@ -277,7 +277,7 @@ class TDE_EXPORT ViewFactory : public KLibFactory
 {
   public:
     virtual KAddressBookView *view( KAB::Core *core, TQWidget *parent,
-                                    const char *name = 0 ) = 0;
+                                    const char *name = nullptr ) = 0;
     /**
       @return The type of the view. This is normally a small one word
       string (ie: Table, Icon, Tree, etc).
@@ -302,13 +302,13 @@ class TDE_EXPORT ViewFactory : public KLibFactory
      */
     virtual ViewConfigureWidget *configureWidget( TDEABC::AddressBook *ab,
                                                   TQWidget *parent,
-                                                  const char *name = 0 );
+                                                  const char *name = nullptr );
 
   protected:
     virtual TQObject* createObject( TQObject*, const char*, const char*,
                                    const TQStringList & )
     {
-      return 0;
+      return nullptr;
     }
 };
 
diff --git a/kaddressbook/kcmconfigs/addhostdialog.h b/kaddressbook/kcmconfigs/addhostdialog.h
index 301b9f9f6..1aa0c8a9d 100644
--- a/kaddressbook/kcmconfigs/addhostdialog.h
+++ b/kaddressbook/kcmconfigs/addhostdialog.h
@@ -38,7 +38,7 @@ class AddHostDialog : public KDialogBase
   
 
   public:
-    AddHostDialog( KPIM::LdapServer* server, TQWidget* parent = 0, const char* name = 0 );
+    AddHostDialog( KPIM::LdapServer* server, TQWidget* parent = nullptr, const char* name = nullptr );
     ~AddHostDialog();
 
   signals:
diff --git a/kaddressbook/kcmconfigs/addresseewidget.cpp b/kaddressbook/kcmconfigs/addresseewidget.cpp
index 35bc17a17..edcb68dd1 100644
--- a/kaddressbook/kcmconfigs/addresseewidget.cpp
+++ b/kaddressbook/kcmconfigs/addresseewidget.cpp
@@ -118,15 +118,15 @@ void NamePartWidget::remove()
 {
   mBox->removeItem( mBox->currentItem() );
   if ( mBox->count() == 0 )
-    selectionChanged( 0 );
+    selectionChanged( nullptr );
 
   emit modified();
 }
 
 void NamePartWidget::selectionChanged( TQListBoxItem *item )
 {
-  mEditButton->setEnabled( item != 0 );
-  mRemoveButton->setEnabled( item != 0 );
+  mEditButton->setEnabled(item);
+  mRemoveButton->setEnabled(item);
 }
 
 
diff --git a/kaddressbook/kcmconfigs/addresseewidget.h b/kaddressbook/kcmconfigs/addresseewidget.h
index 46651903a..336af151e 100644
--- a/kaddressbook/kcmconfigs/addresseewidget.h
+++ b/kaddressbook/kcmconfigs/addresseewidget.h
@@ -40,7 +40,7 @@ class NamePartWidget : public TQWidget
 
   public:
     NamePartWidget( const TQString &title, const TQString &label, TQWidget *parent,
-                    const char *name = 0 );
+                    const char *name = nullptr );
     ~NamePartWidget();
 
     void setNameParts( const TQStringList &list );
@@ -72,7 +72,7 @@ class AddresseeWidget : public TQWidget
   
 
   public:
-    AddresseeWidget( TQWidget *parent, const char *name = 0 );
+    AddresseeWidget( TQWidget *parent, const char *name = nullptr );
     ~AddresseeWidget();
 
     void restoreSettings();
diff --git a/kaddressbook/kcmconfigs/extensionconfigdialog.cpp b/kaddressbook/kcmconfigs/extensionconfigdialog.cpp
index 55eecb18a..f5d7ab6b8 100644
--- a/kaddressbook/kcmconfigs/extensionconfigdialog.cpp
+++ b/kaddressbook/kcmconfigs/extensionconfigdialog.cpp
@@ -32,7 +32,7 @@
 ExtensionConfigDialog::ExtensionConfigDialog( KAB::ExtensionFactory *factory, TDEConfig *config,
                                               TQWidget *parent, const char *name )
   : KDialogBase( Plain, i18n( "Extension Settings" ), Ok | Cancel, Ok, parent,
-                 name, true, true ), mWidget( 0 ), mConfig( config )
+                 name, true, true ), mWidget( nullptr ), mConfig( config )
 {
   TQFrame *page = plainPage();
   TQGridLayout *layout = new TQGridLayout( page, 1, 1, marginHint(), spacingHint() );
diff --git a/kaddressbook/kcmconfigs/extensionconfigdialog.h b/kaddressbook/kcmconfigs/extensionconfigdialog.h
index 5c3ae856c..31f9e86fe 100644
--- a/kaddressbook/kcmconfigs/extensionconfigdialog.h
+++ b/kaddressbook/kcmconfigs/extensionconfigdialog.h
@@ -39,7 +39,7 @@ class ExtensionConfigDialog : public KDialogBase
 
   public:
     ExtensionConfigDialog( KAB::ExtensionFactory *factory, TDEConfig *config,
-                           TQWidget *parent, const char *name = 0 );
+                           TQWidget *parent, const char *name = nullptr );
     ~ExtensionConfigDialog();
 
   protected slots:
diff --git a/kaddressbook/kcmconfigs/kabconfigwidget.h b/kaddressbook/kcmconfigs/kabconfigwidget.h
index 5d6c0506e..0cd89cf71 100644
--- a/kaddressbook/kcmconfigs/kabconfigwidget.h
+++ b/kaddressbook/kcmconfigs/kabconfigwidget.h
@@ -42,7 +42,7 @@ class KABConfigWidget : public TQWidget
   
 
   public:
-    KABConfigWidget( TQWidget *parent, const char *name = 0 );
+    KABConfigWidget( TQWidget *parent, const char *name = nullptr );
 
     void restoreSettings();
     void saveSettings();
diff --git a/kaddressbook/kcmconfigs/kcmkabconfig.cpp b/kaddressbook/kcmconfigs/kcmkabconfig.cpp
index 733663abc..605563c1c 100644
--- a/kaddressbook/kcmconfigs/kcmkabconfig.cpp
+++ b/kaddressbook/kcmconfigs/kcmkabconfig.cpp
@@ -53,10 +53,10 @@ KCMKabConfig::KCMKabConfig( TQWidget *parent, const char *name )
 
   TDEAboutData *about = new TDEAboutData( I18N_NOOP( "kcmkabconfig" ),
                                       I18N_NOOP( "KAddressBook Configure Dialog" ),
-                                      0, 0, TDEAboutData::License_GPL,
+                                      nullptr, nullptr, TDEAboutData::License_GPL,
                                       I18N_NOOP( "(c), 2003 - 2004 Tobias Koenig" ) );
 
-  about->addAuthor( "Tobias Koenig", 0, "tokoe@kde.org" );
+  about->addAuthor( "Tobias Koenig", nullptr, "tokoe@kde.org" );
   setAboutData( about );
 }
 
diff --git a/kaddressbook/kcmconfigs/kcmkabconfig.h b/kaddressbook/kcmconfigs/kcmkabconfig.h
index d97eb1d8d..bd1c004fe 100644
--- a/kaddressbook/kcmconfigs/kcmkabconfig.h
+++ b/kaddressbook/kcmconfigs/kcmkabconfig.h
@@ -34,7 +34,7 @@ class KCMKabConfig : public TDECModule
   
 
   public:
-    KCMKabConfig( TQWidget *parent = 0, const char *name = 0 );
+    KCMKabConfig( TQWidget *parent = nullptr, const char *name = nullptr );
 
     virtual void load();
     virtual void save();
diff --git a/kaddressbook/kcmconfigs/kcmkabcustomfields.h b/kaddressbook/kcmconfigs/kcmkabcustomfields.h
index 5c8cad5e3..a884ff61b 100644
--- a/kaddressbook/kcmconfigs/kcmkabcustomfields.h
+++ b/kaddressbook/kcmconfigs/kcmkabcustomfields.h
@@ -28,7 +28,7 @@
 class KCMKabCustomFields : public KPIM::KCMDesignerFields
 {
   public:
-    KCMKabCustomFields( TQWidget *parent = 0, const char *name = 0 );
+    KCMKabCustomFields( TQWidget *parent = nullptr, const char *name = nullptr );
 
   protected:
     TQString localUiDir();
diff --git a/kaddressbook/kcmconfigs/kcmkabldapconfig.cpp b/kaddressbook/kcmconfigs/kcmkabldapconfig.cpp
index a54951278..ab9cb1e07 100644
--- a/kaddressbook/kcmconfigs/kcmkabldapconfig.cpp
+++ b/kaddressbook/kcmconfigs/kcmkabldapconfig.cpp
@@ -54,10 +54,10 @@ KCMKabLdapConfig::KCMKabLdapConfig( TQWidget *parent, const char *name )
 
   TDEAboutData *about = new TDEAboutData( I18N_NOOP( "kcmkabldapconfig" ),
                                       I18N_NOOP( "KAB LDAP Configure Dialog" ),
-                                      0, 0, TDEAboutData::License_GPL,
+                                      nullptr, nullptr, TDEAboutData::License_GPL,
                                       I18N_NOOP( "(c), 2003 - 2004 Tobias Koenig" ) );
 
-  about->addAuthor( "Tobias Koenig", 0, "tokoe@kde.org" );
+  about->addAuthor( "Tobias Koenig", nullptr, "tokoe@kde.org" );
   setAboutData( about );
 }
 
diff --git a/kaddressbook/kcmconfigs/kcmkabldapconfig.h b/kaddressbook/kcmconfigs/kcmkabldapconfig.h
index 9ea25e83a..82e9cd528 100644
--- a/kaddressbook/kcmconfigs/kcmkabldapconfig.h
+++ b/kaddressbook/kcmconfigs/kcmkabldapconfig.h
@@ -36,7 +36,7 @@ class KCMKabLdapConfig : public TDECModule
   
 
   public:
-    KCMKabLdapConfig( TQWidget *parent = 0, const char *name = 0 );
+    KCMKabLdapConfig( TQWidget *parent = nullptr, const char *name = nullptr );
 
     virtual void load();
     virtual void save();
diff --git a/kaddressbook/kcmconfigs/ldapoptionswidget.cpp b/kaddressbook/kcmconfigs/ldapoptionswidget.cpp
index f8bcfdb92..b10cb639c 100644
--- a/kaddressbook/kcmconfigs/ldapoptionswidget.cpp
+++ b/kaddressbook/kcmconfigs/ldapoptionswidget.cpp
@@ -96,7 +96,7 @@ LDAPOptionsWidget::~LDAPOptionsWidget()
 
 void LDAPOptionsWidget::slotSelectionChanged( TQListViewItem *item )
 {
-  bool state = ( item != 0 );
+  bool state = item != nullptr;
   mEditButton->setEnabled( state );
   mRemoveButton->setEnabled( state );
   mDownButton->setEnabled( item && item->itemBelow() );
diff --git a/kaddressbook/kcmconfigs/ldapoptionswidget.h b/kaddressbook/kcmconfigs/ldapoptionswidget.h
index fbb32a1fb..67925356e 100644
--- a/kaddressbook/kcmconfigs/ldapoptionswidget.h
+++ b/kaddressbook/kcmconfigs/ldapoptionswidget.h
@@ -37,7 +37,7 @@ class LDAPOptionsWidget : public TQWidget
   
 
   public:
-    LDAPOptionsWidget( TQWidget* parent = 0, const char* name = 0 );
+    LDAPOptionsWidget( TQWidget* parent = nullptr, const char* name = nullptr );
     ~LDAPOptionsWidget();
 
     void restoreSettings();
diff --git a/kaddressbook/keywidget.h b/kaddressbook/keywidget.h
index b317eef67..066b1012a 100644
--- a/kaddressbook/keywidget.h
+++ b/kaddressbook/keywidget.h
@@ -37,7 +37,7 @@ class KeyWidget : public TQWidget
   
 
   public:
-    KeyWidget( TQWidget *parent, const char *name = 0 );
+    KeyWidget( TQWidget *parent, const char *name = nullptr );
     ~KeyWidget();
 
     void setKeys( const TDEABC::Key::List &list );
diff --git a/kaddressbook/ldapsearchdialog.h b/kaddressbook/ldapsearchdialog.h
index a10bbfdea..e30da8cdf 100644
--- a/kaddressbook/ldapsearchdialog.h
+++ b/kaddressbook/ldapsearchdialog.h
@@ -53,7 +53,7 @@ class LDAPSearchDialog : public KDialogBase
   
 
   public:
-    LDAPSearchDialog( TDEABC::AddressBook *ab, KABCore *core, TQWidget* parent, const char* name = 0 );
+    LDAPSearchDialog( TDEABC::AddressBook *ab, KABCore *core, TQWidget* parent, const char* name = nullptr );
     ~LDAPSearchDialog();
 
     bool isOK() const { return mIsOK; }
diff --git a/kaddressbook/main.cpp b/kaddressbook/main.cpp
index 22af385de..7816c2631 100644
--- a/kaddressbook/main.cpp
+++ b/kaddressbook/main.cpp
@@ -42,7 +42,7 @@
 
 class KAddressBookApp : public TDEUniqueApplication {
   public:
-    KAddressBookApp() : mMainWin( 0 ), mDefaultIsOpen( false ) {}
+    KAddressBookApp() : mMainWin( nullptr ), mDefaultIsOpen( false ) {}
     ~KAddressBookApp() {}
 
     int newInstance();
diff --git a/kaddressbook/nameeditdialog.h b/kaddressbook/nameeditdialog.h
index 12b749399..ed86136c9 100644
--- a/kaddressbook/nameeditdialog.h
+++ b/kaddressbook/nameeditdialog.h
@@ -54,7 +54,7 @@ class NameEditDialog : public KDialogBase
     };
 
     NameEditDialog( const TDEABC::Addressee &addr, int type,
-                    bool readOnly, TQWidget *parent, const char *name = 0 );
+                    bool readOnly, TQWidget *parent, const char *name = nullptr );
     ~NameEditDialog();
 
     TQString familyName() const;
diff --git a/kaddressbook/phoneeditwidget.h b/kaddressbook/phoneeditwidget.h
index eb1fbf0a5..746105aa6 100644
--- a/kaddressbook/phoneeditwidget.h
+++ b/kaddressbook/phoneeditwidget.h
@@ -94,7 +94,7 @@ class PhoneEditWidget : public TQWidget
   
 
   public:
-    PhoneEditWidget( TQWidget *parent, const char *name = 0 );
+    PhoneEditWidget( TQWidget *parent, const char *name = nullptr );
     ~PhoneEditWidget();
 
     void setPhoneNumbers( const TDEABC::PhoneNumber::List &list );
diff --git a/kaddressbook/printing/detailledstyle.cpp b/kaddressbook/printing/detailledstyle.cpp
index ee702058b..7de37240d 100644
--- a/kaddressbook/printing/detailledstyle.cpp
+++ b/kaddressbook/printing/detailledstyle.cpp
@@ -66,8 +66,8 @@ const char *ContactHeaderBGColor = "ContactHeaderBGColor";
 DetailledPrintStyle::DetailledPrintStyle( PrintingWizard *parent, const char *name )
   : PrintStyle( parent, name ),
     mPageAppearance( new AppearancePage( parent, "AppearancePage" ) ),
-    mPainter( 0 ),
-    mPrintProgress( 0 )
+    mPainter( nullptr ),
+    mPrintProgress( nullptr )
 {
   TDEConfig *config;
   TQFont font;
@@ -119,7 +119,7 @@ DetailledPrintStyle::DetailledPrintStyle( PrintingWizard *parent, const char *na
 DetailledPrintStyle::~DetailledPrintStyle()
 {
   delete mPainter;
-  mPainter = 0;
+  mPainter = nullptr;
 }
 
 void DetailledPrintStyle::print( const TDEABC::Addressee::List &contacts, PrintProgress *progress )
diff --git a/kaddressbook/printing/detailledstyle.h b/kaddressbook/printing/detailledstyle.h
index 4197755e9..c7b012677 100644
--- a/kaddressbook/printing/detailledstyle.h
+++ b/kaddressbook/printing/detailledstyle.h
@@ -39,7 +39,7 @@ class DetailledPrintStyle : public PrintStyle
   
 
   public:
-    DetailledPrintStyle( PrintingWizard *parent, const char *name = 0 );
+    DetailledPrintStyle( PrintingWizard *parent, const char *name = nullptr );
     ~DetailledPrintStyle();
 
     void print( const TDEABC::Addressee::List &contacts, PrintProgress* );
@@ -58,7 +58,7 @@ class DetailledPrintStyle : public PrintStyle
 class DetailledPrintStyleFactory : public PrintStyleFactory
 {
   public:
-    DetailledPrintStyleFactory( PrintingWizard *parent, const char *name = 0 );
+    DetailledPrintStyleFactory( PrintingWizard *parent, const char *name = nullptr );
 
     PrintStyle *create() const;
     TQString description() const;
diff --git a/kaddressbook/printing/kabentrypainter.cpp b/kaddressbook/printing/kabentrypainter.cpp
index 49247ce8a..892fc32e1 100644
--- a/kaddressbook/printing/kabentrypainter.cpp
+++ b/kaddressbook/printing/kabentrypainter.cpp
@@ -511,7 +511,7 @@ bool KABEntryPainter::printAddressee( const TDEABC::Addressee &addr,
 
   y += fmBody.lineSpacing() / 2;
 
-  if ( brect != 0 )
+  if (brect)
     *brect = TQRect( 0, top, Width, y - top );
 
   if ( y < Height )
diff --git a/kaddressbook/printing/kabentrypainter.h b/kaddressbook/printing/kabentrypainter.h
index cd933b579..7e3eea2cb 100644
--- a/kaddressbook/printing/kabentrypainter.h
+++ b/kaddressbook/printing/kabentrypainter.h
@@ -60,7 +60,7 @@ class KABEntryPainter
      */
     bool printAddressee( const TDEABC::Addressee &addr, const TQRect &window,
                          TQPainter *p, int top = 0, bool fake = false,
-                         TQRect *rect = 0 );
+                         TQRect *rect = nullptr );
 
     void setForegroundColor( const TQColor &color = TQt::black );
     void setBackgroundColor( const TQColor &color = TQt::black );
diff --git a/kaddressbook/printing/mikesstyle.h b/kaddressbook/printing/mikesstyle.h
index ccaf4a664..9373fc2fd 100644
--- a/kaddressbook/printing/mikesstyle.h
+++ b/kaddressbook/printing/mikesstyle.h
@@ -55,7 +55,7 @@ class MikesStyle : public PrintStyle
 class MikesStyleFactory : public PrintStyleFactory
 {
   public:
-    MikesStyleFactory( PrintingWizard *parent, const char *name = 0 );
+    MikesStyleFactory( PrintingWizard *parent, const char *name = nullptr );
 
     PrintStyle *create() const;
     TQString description() const;
diff --git a/kaddressbook/printing/printingwizard.cpp b/kaddressbook/printing/printingwizard.cpp
index 578c2ce0f..c690a60ae 100644
--- a/kaddressbook/printing/printingwizard.cpp
+++ b/kaddressbook/printing/printingwizard.cpp
@@ -56,7 +56,7 @@ PrintingWizard::PrintingWizard( KPrinter *printer, TDEABC::AddressBook* ab,
                                 const TQStringList& selection, TQWidget *parent,
                                 const char* name )
   : KWizard( parent, name ), mPrinter( printer ), mAddressBook( ab ),
-    mSelection( selection ), mStyle( 0 )
+    mSelection( selection ), mStyle( nullptr )
 {
   mSelectionPage = new SelectionPage( this );
   mSelectionPage->setUseSelection( !selection.isEmpty() );
@@ -114,7 +114,7 @@ void PrintingWizard::slotStyleSelected( int index )
   if ( mStyle )
     mStyle->hidePages();
 
-  if ( mStyleList.at( index ) != 0 )
+  if (mStyleList.at( index ))
     mStyle = mStyleList.at( index );
   else {
     PrintStyleFactory *factory = mStyleFactories.at( index );
@@ -131,7 +131,7 @@ void PrintingWizard::slotStyleSelected( int index )
 
   setFinishEnabled( page( pageCount() - 1 ), true );
 
-  if ( mStyle->preferredSortField() != 0 ) {
+  if (mStyle->preferredSortField()) {
     mStylePage->setSortField( mStyle->preferredSortField() );
     mStylePage->setSortAscending( mStyle->preferredSortType() );
   }
@@ -158,7 +158,7 @@ void PrintingWizard::print()
   // prepare list of contacts to print:
 
   TDEABC::AddresseeList list;
-  if ( mStyle != 0 ) {
+  if (mStyle) {
     if ( mSelectionPage->useSelection() ) {
       TQStringList::ConstIterator it;
       for ( it = mSelection.begin(); it != mSelection.end(); ++it ) {
diff --git a/kaddressbook/printing/printingwizard.h b/kaddressbook/printing/printingwizard.h
index bd26b2c1e..c77f664d7 100644
--- a/kaddressbook/printing/printingwizard.h
+++ b/kaddressbook/printing/printingwizard.h
@@ -59,7 +59,7 @@ class PrintingWizard : public KWizard
     PrintingWizard( KPrinter *printer,
                     TDEABC::AddressBook* ab,
                     const TQStringList& selection,
-                    TQWidget *parent = 0, const char *name = 0 );
+                    TQWidget *parent = nullptr, const char *name = nullptr );
     ~PrintingWizard();
 
     /**
diff --git a/kaddressbook/printing/printprogress.h b/kaddressbook/printing/printprogress.h
index b23f069a5..dbfbdde68 100644
--- a/kaddressbook/printing/printprogress.h
+++ b/kaddressbook/printing/printprogress.h
@@ -43,7 +43,7 @@ class PrintProgress : public TQWidget
   
 
   public:
-    PrintProgress( TQWidget *parent, const char *name = 0 );
+    PrintProgress( TQWidget *parent, const char *name = nullptr );
     ~PrintProgress();
 
     /**
diff --git a/kaddressbook/printing/printstyle.cpp b/kaddressbook/printing/printstyle.cpp
index ca3fafb91..d706dbdcc 100644
--- a/kaddressbook/printing/printstyle.cpp
+++ b/kaddressbook/printing/printstyle.cpp
@@ -33,7 +33,7 @@ using namespace KABPrinting;
 
 
 PrintStyle::PrintStyle( PrintingWizard* parent, const char* name )
-  : TQObject( parent, name ), mWizard( parent ), mSortField( 0 )
+  : TQObject( parent, name ), mWizard( parent ), mSortField( nullptr )
 {
 }
 
@@ -84,7 +84,7 @@ void PrintStyle::addPage( TQWidget *page, const TQString &title )
 
 void PrintStyle::showPages()
 {
-  TQWidget *wdg = 0;
+  TQWidget *wdg = nullptr;
   int i = 0;
   for ( wdg = mPageList.first(); wdg; wdg = mPageList.next(), ++i ) {
     mWizard->addPage( wdg, mPageTitles[ i ] );
diff --git a/kaddressbook/printing/printstyle.h b/kaddressbook/printing/printstyle.h
index 6984a7f50..2b1fecfa5 100644
--- a/kaddressbook/printing/printstyle.h
+++ b/kaddressbook/printing/printstyle.h
@@ -63,7 +63,7 @@ class PrintStyle : public TQObject
   
 
   public:
-    PrintStyle( PrintingWizard* parent, const char* name = 0 );
+    PrintStyle( PrintingWizard* parent, const char* name = nullptr );
     virtual ~PrintStyle();
 
     /**
@@ -151,7 +151,7 @@ class PrintStyle : public TQObject
 class PrintStyleFactory
 {
   public:
-    PrintStyleFactory( PrintingWizard* parent, const char* name = 0 );
+    PrintStyleFactory( PrintingWizard* parent, const char* name = nullptr );
     virtual ~PrintStyleFactory();
 
     virtual PrintStyle *create() const = 0;
diff --git a/kaddressbook/printing/selectionpage.h b/kaddressbook/printing/selectionpage.h
index 06a6f3a54..1861e767b 100644
--- a/kaddressbook/printing/selectionpage.h
+++ b/kaddressbook/printing/selectionpage.h
@@ -38,7 +38,7 @@ class SelectionPage : public TQWidget
   
 
   public:
-    SelectionPage( TQWidget* parent = 0, const char* name = 0 );
+    SelectionPage( TQWidget* parent = nullptr, const char* name = nullptr );
     ~SelectionPage();
 
     void setFilters( const TQStringList& );
diff --git a/kaddressbook/printing/stylepage.h b/kaddressbook/printing/stylepage.h
index 6bccdda0c..c039d7248 100644
--- a/kaddressbook/printing/stylepage.h
+++ b/kaddressbook/printing/stylepage.h
@@ -41,7 +41,7 @@ class StylePage : public TQWidget
   
 
   public:
-    StylePage( TDEABC::AddressBook *ab, TQWidget* parent = 0, const char* name = 0 );
+    StylePage( TDEABC::AddressBook *ab, TQWidget* parent = nullptr, const char* name = nullptr );
     ~StylePage();
 
     /**
diff --git a/kaddressbook/searchmanager.h b/kaddressbook/searchmanager.h
index 4646f90b6..b14f84495 100644
--- a/kaddressbook/searchmanager.h
+++ b/kaddressbook/searchmanager.h
@@ -48,7 +48,7 @@ class SearchManager : public TQObject
     };
 
     SearchManager( TDEABC::AddressBook *ab,
-                   TQObject *parent, const char *name = 0 );
+                   TQObject *parent, const char *name = nullptr );
 
     /**
       This method takes a pattern and searches for a match of the specified
diff --git a/kaddressbook/secrecywidget.h b/kaddressbook/secrecywidget.h
index 0d43bc5b9..a629eaf09 100644
--- a/kaddressbook/secrecywidget.h
+++ b/kaddressbook/secrecywidget.h
@@ -35,7 +35,7 @@ class SecrecyWidget : public TQWidget
   
 
   public:
-    SecrecyWidget( TQWidget *parent, const char *name = 0 );
+    SecrecyWidget( TQWidget *parent, const char *name = nullptr );
     ~SecrecyWidget();
 
     void setSecrecy( const TDEABC::Secrecy &secrecy );
diff --git a/kaddressbook/simpleaddresseeeditor.h b/kaddressbook/simpleaddresseeeditor.h
index 1efda9e89..1d056fafe 100644
--- a/kaddressbook/simpleaddresseeeditor.h
+++ b/kaddressbook/simpleaddresseeeditor.h
@@ -34,7 +34,7 @@ class SimpleAddresseeEditor : public AddresseeEditorBase
     TQ_OBJECT
   
   public:
-    SimpleAddresseeEditor( TQWidget *parent, const char *name = 0 );
+    SimpleAddresseeEditor( TQWidget *parent, const char *name = nullptr );
     ~SimpleAddresseeEditor();
 
     void setAddressee( const TDEABC::Addressee& );
diff --git a/kaddressbook/soundwidget.h b/kaddressbook/soundwidget.h
index 530da0982..30ec7ec16 100644
--- a/kaddressbook/soundwidget.h
+++ b/kaddressbook/soundwidget.h
@@ -39,7 +39,7 @@ class SoundWidget : public KAB::ContactEditorWidget
   
 
   public:
-    SoundWidget( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = 0 );
+    SoundWidget( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = nullptr );
     ~SoundWidget();
 
     void loadContact( TDEABC::Addressee *addr );
diff --git a/kaddressbook/thumbnailcreator/ldifvcardcreator.cpp b/kaddressbook/thumbnailcreator/ldifvcardcreator.cpp
index 7acdd9d30..67991f9b2 100644
--- a/kaddressbook/thumbnailcreator/ldifvcardcreator.cpp
+++ b/kaddressbook/thumbnailcreator/ldifvcardcreator.cpp
@@ -54,7 +54,7 @@ extern "C"
 }
 
 VCard_LDIFCreator::VCard_LDIFCreator()
-  : mSplitter( 0 )
+  : mSplitter( nullptr )
 {
 }
 
@@ -165,7 +165,7 @@ bool VCard_LDIFCreator::createImageSmall()
     TQString pixmap = locate( "data", "konqueror/pics/thumbnailfont_7x4.png" );
     if ( pixmap.isEmpty() ) {
       delete mSplitter;
-      mSplitter=0;
+      mSplitter=nullptr;
       kdWarning() << "VCard_LDIFCreator: Font image \"thumbnailfont_7x4.png\" not found!" << endl;
       return false;
     }
diff --git a/kaddressbook/typecombo.h b/kaddressbook/typecombo.h
index 4b12ef867..e48b73acf 100644
--- a/kaddressbook/typecombo.h
+++ b/kaddressbook/typecombo.h
@@ -37,7 +37,7 @@ class TypeCombo : public KComboBox
     typedef typename T::List List;
     typedef typename T::List::Iterator Iterator;
 
-    TypeCombo( List &list, TQWidget *parent, const char *name = 0 );
+    TypeCombo( List &list, TQWidget *parent, const char *name = nullptr );
 
     void setLineEdit( TQLineEdit *edit ) { mLineEdit = edit; }
     TQLineEdit *lineEdit() const { return mLineEdit; }
diff --git a/kaddressbook/viewconfigurefieldspage.h b/kaddressbook/viewconfigurefieldspage.h
index f1718bd0f..58c307df1 100644
--- a/kaddressbook/viewconfigurefieldspage.h
+++ b/kaddressbook/viewconfigurefieldspage.h
@@ -41,8 +41,8 @@ class ViewConfigureFieldsPage : public TQWidget
   
 
   public:
-    ViewConfigureFieldsPage( TDEABC::AddressBook *ab, TQWidget *parent = 0,
-                             const char *name = 0 );
+    ViewConfigureFieldsPage( TDEABC::AddressBook *ab, TQWidget *parent = nullptr,
+                             const char *name = nullptr );
 
     void restoreSettings( TDEConfig* );
     void saveSettings( TDEConfig* );
diff --git a/kaddressbook/viewconfigurefilterpage.h b/kaddressbook/viewconfigurefilterpage.h
index a879337fc..47e6552df 100644
--- a/kaddressbook/viewconfigurefilterpage.h
+++ b/kaddressbook/viewconfigurefilterpage.h
@@ -37,7 +37,7 @@ class ViewConfigureFilterPage : public TQWidget
   
 
   public:
-    ViewConfigureFilterPage( TQWidget *parent, const char *name = 0 );
+    ViewConfigureFilterPage( TQWidget *parent, const char *name = nullptr );
     ~ViewConfigureFilterPage();
 
     void restoreSettings( TDEConfig* );
diff --git a/kaddressbook/viewconfigurewidget.h b/kaddressbook/viewconfigurewidget.h
index 24077e64a..b4c8b06c2 100644
--- a/kaddressbook/viewconfigurewidget.h
+++ b/kaddressbook/viewconfigurewidget.h
@@ -51,7 +51,7 @@ class TDE_EXPORT ViewConfigureWidget : public KAB::ConfigureWidget
   
 
   public:
-    ViewConfigureWidget( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = 0 );
+    ViewConfigureWidget( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = nullptr );
     virtual ~ViewConfigureWidget();
 
     /**
@@ -92,7 +92,7 @@ class ViewConfigureDialog : public KDialogBase
 
   public:
     ViewConfigureDialog( ViewConfigureWidget *wdg, const TQString &viewName,
-                         TQWidget *parent, const char *name = 0 );
+                         TQWidget *parent, const char *name = nullptr );
     ~ViewConfigureDialog();
 
     void restoreSettings( TDEConfig* );
diff --git a/kaddressbook/viewmanager.cpp b/kaddressbook/viewmanager.cpp
index 39cd1b306..578dc01c9 100644
--- a/kaddressbook/viewmanager.cpp
+++ b/kaddressbook/viewmanager.cpp
@@ -49,8 +49,8 @@
 #include "viewmanager.h"
 
 ViewManager::ViewManager( KAB::Core *core, TQWidget *parent, const char *name )
-  : TQWidget( parent, name ), mCore( core ), mActiveView( 0 ),
-    mFilterSelectionWidget( 0 )
+  : TQWidget( parent, name ), mCore( core ), mActiveView( nullptr ),
+    mFilterSelectionWidget( nullptr )
 {
   initGUI();
   initActions();
@@ -150,7 +150,7 @@ TDEABC::Field *ViewManager::currentSortField() const
   if ( mActiveView )
     return mActiveView->sortField();
   else
-    return 0;
+    return nullptr;
 }
 
 TDEABC::Field::List ViewManager::viewFields() const
@@ -178,12 +178,12 @@ void ViewManager::setFirstSelected( bool selected )
 void ViewManager::unloadViews()
 {
   mViewDict.clear();
-  mActiveView = 0;
+  mActiveView = nullptr;
 }
 
 void ViewManager::setActiveView( const TQString &name )
 {
-  KAddressBookView *view = 0;
+  KAddressBookView *view = nullptr;
 
   // Check that this isn't the same as the current active view
   if ( mActiveView && ( mActiveView->caption() == name ) )
@@ -197,7 +197,7 @@ void ViewManager::setActiveView( const TQString &name )
   view = mViewDict.find( name );
 
   // Check if we found the view. If we didn't, then we need to create it
-  if ( view == 0 ) {
+  if (!view) {
     TDEConfig *config = mCore->config();
     TDEConfigGroupSaver saver( config, name );
     TQString type = config->readEntry( "Type", "Table" );
@@ -265,13 +265,13 @@ void ViewManager::editView()
     return;
 
   ViewFactory *factory = mViewFactoryDict.find( mActiveView->type() );
-  ViewConfigureWidget *wdg = 0;
+  ViewConfigureWidget *wdg = nullptr;
 
   if ( factory ) {
     // Save the filters so the dialog has the latest set
     Filter::save( mCore->config(), "Filter", mFilterList );
 
-    wdg = factory->configureWidget( mCore->addressBook(), 0 );
+    wdg = factory->configureWidget( mCore->addressBook(), nullptr );
   }
 
   if ( wdg ) {
@@ -317,7 +317,7 @@ void ViewManager::deleteView()
     config->deleteGroup( mActiveView->caption() );
 
     mViewDict.remove( mActiveView->caption() );
-    mActiveView = 0;
+    mActiveView = nullptr;
 
     // we are in an invalid state now, but that should be fixed after
     // we emit the signal
diff --git a/kaddressbook/viewmanager.h b/kaddressbook/viewmanager.h
index ce9abbc23..a95c0ede6 100644
--- a/kaddressbook/viewmanager.h
+++ b/kaddressbook/viewmanager.h
@@ -53,7 +53,7 @@ class ViewManager : public TQWidget
   
 
   public:
-    ViewManager( KAB::Core *core, TQWidget *parent, const char *name = 0 );
+    ViewManager( KAB::Core *core, TQWidget *parent, const char *name = nullptr );
     ~ViewManager();
 
     void restoreSettings();
diff --git a/kaddressbook/views/cardview.cpp b/kaddressbook/views/cardview.cpp
index 749dc13f6..bf3e12f0e 100644
--- a/kaddressbook/views/cardview.cpp
+++ b/kaddressbook/views/cardview.cpp
@@ -42,7 +42,7 @@
 class CardViewTip : public TQLabel
 {
   public:
-    CardViewTip( TQWidget *parent = 0, const char *name = 0 )
+    CardViewTip( TQWidget *parent = nullptr, const char *name = nullptr )
       : TQLabel( parent, name )
     {
       setPalette( TQToolTip::palette() );
@@ -76,7 +76,7 @@ class CardViewItemList : public TQPtrList<CardViewItem>
       if ( cItem1 == cItem2 )
           return 0;
 
-      if ( (cItem1 == 0) || (cItem2 == 0) )
+      if (!cItem1 || !cItem2)
           return cItem1 ? -1 : 1;
 
       if ( cItem1->caption() < cItem2->caption() )
@@ -133,7 +133,7 @@ class CardViewPrivate
        mItemSpacing( 10 ),
        mItemWidth( 200 ),
        mMaxFieldLines( INT_MAX ),
-       mCurrentItem( 0L ),
+       mCurrentItem( nullptr ),
        mLastClickPos( TQPoint(0, 0) ),
        mRubberBandAnchor( 0 ),
        mCompText( TQString() )
@@ -203,11 +203,11 @@ CardViewItem::CardViewItem( CardView *parent, const TQString &caption )
 CardViewItem::~CardViewItem()
 {
   // Remove ourself from the view
-  if ( mView != 0 )
+  if (mView)
     mView->takeItem( this );
 
   delete d;
-  d = 0;
+  d = nullptr;
 }
 
 void CardViewItem::initialize()
@@ -218,7 +218,7 @@ void CardViewItem::initialize()
   d->hcache = 0;
 
   // Add ourself to the view
-  if ( mView != 0 )
+  if (mView)
     mView->insertItem( this );
 }
 
@@ -440,7 +440,7 @@ TQString CardViewItem::trimString( const TQString &text, int width,
 
 CardViewItem *CardViewItem::nextItem() const
 {
-  CardViewItem *item = 0;
+  CardViewItem *item = nullptr;
 
   if ( mView )
     item = mView->itemAfter( this );
@@ -552,7 +552,7 @@ CardViewItem::Field *CardViewItem::fieldAt( const TQPoint & itempos ) const
   int iy = itempos.y();
   // skip below caption
   if ( iy <= ypos )
-    return 0;
+    return nullptr;
   // try find a field
   bool showEmpty = mView->showEmptyFields();
   int fh = mView->d->mFm->height();
@@ -565,7 +565,7 @@ CardViewItem::Field *CardViewItem::fieldAt( const TQPoint & itempos ) const
       break;
   }
 
-  return f ? f : 0;
+  return f ? f : nullptr;
 }
 
 
@@ -603,7 +603,7 @@ CardView::~CardView()
   delete d->mFm;
   delete d->mBFm;
   delete d;
-  d = 0;
+  d = nullptr;
 }
 
 void CardView::insertItem( CardViewItem *item )
@@ -666,7 +666,7 @@ void CardView::setCurrentItem( CardViewItem *item )
 
 CardViewItem *CardView::itemAt( const TQPoint &viewPos ) const
 {
-  CardViewItem *item = 0;
+  CardViewItem *item = nullptr;
   TQPtrListIterator<CardViewItem> iter( d->mItemList );
   bool found = false;
   for ( iter.toFirst(); iter.current() && !found; ++iter ) {
@@ -678,7 +678,7 @@ CardViewItem *CardView::itemAt( const TQPoint &viewPos ) const
   if ( found )
     return item;
 
-  return 0;
+  return nullptr;
 }
 
 TQRect CardView::itemRect( const CardViewItem *item ) const
@@ -720,7 +720,7 @@ void CardView::selectAll( bool state )
       }
     }
 
-    emit selectionChanged( 0 );
+    emit selectionChanged( nullptr );
   } else if ( d->mSelectionMode != CardView::Single ) {
     for ( iter.toFirst(); iter.current(); ++iter ) {
       (*iter)->setSelected( true );
@@ -736,7 +736,7 @@ void CardView::selectAll( bool state )
 
 void CardView::setSelected( CardViewItem *item, bool selected )
 {
-  if ( (item == 0) || (item->isSelected() == selected) )
+  if (!item || item->isSelected() == selected)
     return;
 
   if ( selected && d->mCurrentItem != item ) {
@@ -759,7 +759,7 @@ void CardView::setSelected( CardViewItem *item, bool selected )
       emit selectionChanged( item );
     } else {
       emit selectionChanged();
-      emit selectionChanged( 0 );
+      emit selectionChanged( nullptr );
     }
   } else if ( d->mSelectionMode == CardView::Multi ) {
     item->setSelected( selected );
@@ -791,7 +791,7 @@ CardViewItem *CardView::selectedItem() const
       return *iter;
   }
 
-  return 0;
+  return nullptr;
 }
 
 CardViewItem *CardView::firstItem() const
@@ -810,7 +810,7 @@ CardViewItem *CardView::findItem( const TQString &text, const TQString &label,
   // If the text is empty, we will return null, since empty text will
   // match anything!
   if ( text.isEmpty() )
-    return 0;
+    return nullptr;
 
   TQPtrListIterator<CardViewItem> iter( d->mItemList );
   if ( compare & TQt::BeginsWith ) {
@@ -824,7 +824,7 @@ CardViewItem *CardView::findItem( const TQString &text, const TQString &label,
     kdDebug(5720) << "CardView::findItem: search method not implemented" << endl;
   }
 
-  return 0;
+  return nullptr;
 }
 
 uint CardView::columnWidth() const
@@ -905,8 +905,8 @@ void CardView::calcLayout()
   d->mSeparatorList.clear();
 
   TQPtrListIterator<CardViewItem> iter( d->mItemList );
-  CardViewItem *item = 0;
-  CardViewSeparator *sep = 0;
+  CardViewItem *item = nullptr;
+  CardViewSeparator *sep = nullptr;
   xPos += cardSpacing;
 
   for ( iter.toFirst(); iter.current(); ++iter ) {
@@ -994,7 +994,7 @@ void CardView::contentsMousePressEvent( TQMouseEvent *e )
 
   CardViewItem *item = itemAt( e->pos() );
 
-  if ( item == 0 ) {
+  if (!item) {
     d->mLastClickOnItem = false;
     if ( d->mOnSeparator) {
       d->mResizeAnchor = e->x() + contentsX();
@@ -1219,7 +1219,7 @@ void CardView::keyPressEvent( TQKeyEvent *e )
   }
 
   uint pos = d->mItemList.findRef( d->mCurrentItem );
-  CardViewItem *aItem = 0;
+  CardViewItem *aItem = nullptr;
   CardViewItem *old = d->mCurrentItem;
 
   switch ( e->key() ) {
diff --git a/kaddressbook/views/colorlistbox.cpp b/kaddressbook/views/colorlistbox.cpp
index a72a644b8..af3d5c7dd 100644
--- a/kaddressbook/views/colorlistbox.cpp
+++ b/kaddressbook/views/colorlistbox.cpp
@@ -121,7 +121,7 @@ void ColorListBox::dragMoveEvent( TQDragMoveEvent *e )
   if( KColorDrag::canDecode(e) && isEnabled() )
   {
     ColorListItem *item = (ColorListItem*)itemAt( e->pos() );
-    if( item != 0 )
+    if(item)
     {
       setCurrentItem ( item );
     }
diff --git a/kaddressbook/views/colorlistbox.h b/kaddressbook/views/colorlistbox.h
index f860bf823..28e204303 100644
--- a/kaddressbook/views/colorlistbox.h
+++ b/kaddressbook/views/colorlistbox.h
@@ -29,7 +29,7 @@ class ColorListBox : public TDEListBox
   
 
   public:
-    ColorListBox( TQWidget *parent=0, const char * name=0, WFlags f=0 );
+    ColorListBox( TQWidget *parent=nullptr, const char * name=nullptr, WFlags f=0 );
     void setColor( uint index, const TQColor &color );
     TQColor color( uint index ) const;
 
diff --git a/kaddressbook/views/configurecardviewdialog.h b/kaddressbook/views/configurecardviewdialog.h
index c57594cb6..03547489b 100644
--- a/kaddressbook/views/configurecardviewdialog.h
+++ b/kaddressbook/views/configurecardviewdialog.h
@@ -83,7 +83,7 @@ class CardViewLookNFeelPage : public TQVBox {
   
 
   public:
-    CardViewLookNFeelPage( TQWidget *parent=0, const char *name=0 );
+    CardViewLookNFeelPage( TQWidget *parent=nullptr, const char *name=nullptr );
     ~CardViewLookNFeelPage();
 
     void restoreSettings( TDEConfig* );
diff --git a/kaddressbook/views/configuretableviewdialog.h b/kaddressbook/views/configuretableviewdialog.h
index fdc644be5..49ad2a82b 100644
--- a/kaddressbook/views/configuretableviewdialog.h
+++ b/kaddressbook/views/configuretableviewdialog.h
@@ -66,7 +66,7 @@ class LookAndFeelPage : public TQWidget
   
 
   public:
-    LookAndFeelPage( TQWidget *parent, const char *name = 0 );
+    LookAndFeelPage( TQWidget *parent, const char *name = nullptr );
     ~LookAndFeelPage() {}
 
     void restoreSettings( TDEConfig* );
diff --git a/kaddressbook/views/contactlistview.h b/kaddressbook/views/contactlistview.h
index a2d70aa26..4beb4d84f 100644
--- a/kaddressbook/views/contactlistview.h
+++ b/kaddressbook/views/contactlistview.h
@@ -91,7 +91,7 @@ public:
   ContactListView(KAddressBookTableView *view,
                   TDEABC::AddressBook *doc,
                   TQWidget *parent,
-                  const char *name = 0L );
+                  const char *name = nullptr );
   virtual ~ContactListView() {}
   //void resort();
 
diff --git a/kaddressbook/views/kaddressbookcardview.cpp b/kaddressbook/views/kaddressbookcardview.cpp
index a61ba3a92..3dfd78769 100644
--- a/kaddressbook/views/kaddressbookcardview.cpp
+++ b/kaddressbook/views/kaddressbookcardview.cpp
@@ -53,7 +53,7 @@ class CardViewFactory : public ViewFactory
     TQString description() const { return i18n( "Rolodex style cards represent contacts." ); }
 
     ViewConfigureWidget *configureWidget( TDEABC::AddressBook *ab, TQWidget *parent,
-                                          const char *name = 0 )
+                                          const char *name = nullptr )
     {
       return new ConfigureCardViewWidget( ab, parent, name );
     }
diff --git a/kaddressbook/views/kaddressbookcardview.h b/kaddressbook/views/kaddressbookcardview.h
index 447614ad3..7c8c30734 100644
--- a/kaddressbook/views/kaddressbookcardview.h
+++ b/kaddressbook/views/kaddressbookcardview.h
@@ -47,7 +47,7 @@ class KAddressBookCardView : public KAddressBookView
 
   public:
     KAddressBookCardView( KAB::Core *core, TQWidget *parent,
-                          const char *name = 0 );
+                          const char *name = nullptr );
     virtual ~KAddressBookCardView();
 
     virtual TQStringList selectedUids();
@@ -80,7 +80,7 @@ class AddresseeCardView : public CardView
   TQ_OBJECT
   
   public:
-    AddresseeCardView( TQWidget *parent, const char *name = 0 );
+    AddresseeCardView( TQWidget *parent, const char *name = nullptr );
     ~AddresseeCardView();
 
   signals:
diff --git a/kaddressbook/views/kaddressbookiconview.cpp b/kaddressbook/views/kaddressbookiconview.cpp
index 66aff6d12..40b1dbc16 100644
--- a/kaddressbook/views/kaddressbookiconview.cpp
+++ b/kaddressbook/views/kaddressbookiconview.cpp
@@ -88,7 +88,7 @@ TQDragObject *AddresseeIconView::dragObject()
   emit startAddresseeDrag();
 
   // We never want IconView to start the drag
-  return 0;
+  return nullptr;
 }
 
 
diff --git a/kaddressbook/views/kaddressbookiconview.h b/kaddressbook/views/kaddressbookiconview.h
index d4d7bf932..70d3a947b 100644
--- a/kaddressbook/views/kaddressbookiconview.h
+++ b/kaddressbook/views/kaddressbookiconview.h
@@ -46,7 +46,7 @@ class KAddressBookIconView : public KAddressBookView
 
   public:
     KAddressBookIconView( KAB::Core *core, TQWidget *parent,
-                          const char *name = 0 );
+                          const char *name = nullptr );
     virtual ~KAddressBookIconView();
 
     virtual TQStringList selectedUids();
@@ -79,7 +79,7 @@ class AddresseeIconView : public TDEIconView
   
 
   public:
-    AddresseeIconView( TQWidget *parent, const char *name = 0 );
+    AddresseeIconView( TQWidget *parent, const char *name = nullptr );
     ~AddresseeIconView();
 
   signals:
diff --git a/kaddressbook/views/kaddressbooktableview.cpp b/kaddressbook/views/kaddressbooktableview.cpp
index a7d0d38b0..0ab2bc5fa 100644
--- a/kaddressbook/views/kaddressbooktableview.cpp
+++ b/kaddressbook/views/kaddressbooktableview.cpp
@@ -72,7 +72,7 @@ class TableViewFactory : public ViewFactory
                                   "the table holds a field of the contact." ); }
 
     ViewConfigureWidget *configureWidget( TDEABC::AddressBook *ab, TQWidget *parent,
-                                          const char *name = 0 )
+                                          const char *name = nullptr )
     {
       return new ConfigureTableViewWidget( ab, parent, name );
     }
@@ -92,8 +92,8 @@ KAddressBookTableView::KAddressBookTableView( KAB::Core *core,
   mMainLayout = new TQVBoxLayout( viewWidget(), 2 );
 
   // The list view will be created when the config is read.
-  mListView = 0;
-  mIMProxy = 0;
+  mListView = nullptr;
+  mIMProxy = nullptr;
 }
 
 KAddressBookTableView::~KAddressBookTableView()
@@ -118,7 +118,7 @@ void KAddressBookTableView::reconstructListView()
 
   mListView = new ContactListView( this, core()->addressBook(), viewWidget() );
 
-  mListView->setShowIM( mIMProxy != 0 );
+  mListView->setShowIM(mIMProxy);
 
   // Add the columns
   const TDEABC::Field::List fieldList( fields() );
@@ -194,7 +194,7 @@ void KAddressBookTableView::readConfig( TDEConfig *config )
     if ( mIMProxy ) {
       disconnect( mIMProxy, TQ_SIGNAL( sigContactPresenceChanged( const TQString& ) ),
                   this, TQ_SLOT( updatePresence( const TQString& ) ) );
-      mIMProxy = 0;
+      mIMProxy = nullptr;
     }
   }
 
@@ -229,7 +229,7 @@ void KAddressBookTableView::refresh( const TQString &uid )
 
     mListView->clear();
 
-    currentItem = 0;
+    currentItem = nullptr;
     const TDEABC::Addressee::List addresseeList( addressees() );
     TDEABC::Addressee::List::ConstIterator it( addresseeList.begin() );
     const TDEABC::Addressee::List::ConstIterator endIt( addresseeList.end() );
@@ -359,7 +359,7 @@ void KAddressBookTableView::updatePresence( const TQString &uid )
   ContactListViewItem *ceItem;
   for ( item = mListView->firstChild(); item; item = item->itemBelow() ) {
     ceItem = dynamic_cast<ContactListViewItem*>( item );
-    if ( ( ceItem != 0L ) && ( ceItem->addressee().uid() == uid ) ) {
+    if (ceItem && ceItem->addressee().uid() == uid) {
       ceItem->setHasIM( true );
       ceItem->refresh();
       break;
diff --git a/kaddressbook/views/kaddressbooktableview.h b/kaddressbook/views/kaddressbooktableview.h
index 432a2164b..8e75e9f24 100644
--- a/kaddressbook/views/kaddressbooktableview.h
+++ b/kaddressbook/views/kaddressbooktableview.h
@@ -66,7 +66,7 @@ friend class ContactListView;
 
   public:
     KAddressBookTableView( KAB::Core *core, TQWidget *parent,
-                           const char *name = 0 );
+                           const char *name = nullptr );
     virtual ~KAddressBookTableView();
 
     virtual void refresh( const TQString &uid = TQString() );
diff --git a/kaddressbook/xxport/bookmark_xxport.h b/kaddressbook/xxport/bookmark_xxport.h
index 03fe7d0df..9b46f4b9d 100644
--- a/kaddressbook/xxport/bookmark_xxport.h
+++ b/kaddressbook/xxport/bookmark_xxport.h
@@ -33,7 +33,7 @@ class BookmarkXXPort : public KAB::XXPort
   
 
   public:
-    BookmarkXXPort( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = 0 );
+    BookmarkXXPort( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = nullptr );
 
     TQString identifier() const { return "bookmark"; }
 
diff --git a/kaddressbook/xxport/csv_xxport.h b/kaddressbook/xxport/csv_xxport.h
index 473507b65..c66b4cdaa 100644
--- a/kaddressbook/xxport/csv_xxport.h
+++ b/kaddressbook/xxport/csv_xxport.h
@@ -32,7 +32,7 @@ class CSVXXPort : public KAB::XXPort
   
 
   public:
-    CSVXXPort( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = 0 );
+    CSVXXPort( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = nullptr );
 
     TQString identifier() const { return "csv"; }
 
diff --git a/kaddressbook/xxport/csvimportdialog.h b/kaddressbook/xxport/csvimportdialog.h
index 2dce71f49..d10fddc4d 100644
--- a/kaddressbook/xxport/csvimportdialog.h
+++ b/kaddressbook/xxport/csvimportdialog.h
@@ -45,7 +45,7 @@ class CSVImportDialog : public KDialogBase
 
   public:
     CSVImportDialog( TDEABC::AddressBook *ab, TQWidget *parent,
-                     const char *name = 0 );
+                     const char *name = nullptr );
     ~CSVImportDialog();
 
     TDEABC::AddresseeList contacts() const;
diff --git a/kaddressbook/xxport/eudora_xxport.cpp b/kaddressbook/xxport/eudora_xxport.cpp
index f310cb598..f81de70eb 100644
--- a/kaddressbook/xxport/eudora_xxport.cpp
+++ b/kaddressbook/xxport/eudora_xxport.cpp
@@ -47,7 +47,7 @@ EudoraXXPort::EudoraXXPort( TDEABC::AddressBook *ab, TQWidget *parent, const cha
 TDEABC::AddresseeList EudoraXXPort::importContacts( const TQString& ) const
 {
   TQString fileName = KFileDialog::getOpenFileName( TQDir::homeDirPath(),
-		"*.[tT][xX][tT]|" + i18n("Eudora Light Addressbook (*.txt)"), 0 );
+		"*.[tT][xX][tT]|" + i18n("Eudora Light Addressbook (*.txt)"), nullptr );
   if ( fileName.isEmpty() )
     return TDEABC::AddresseeList();
 
@@ -57,7 +57,7 @@ TDEABC::AddresseeList EudoraXXPort::importContacts( const TQString& ) const
 
   TQString line;
   TQTextStream stream( &file );
-  TDEABC::Addressee *a = 0;
+  TDEABC::Addressee *a = nullptr;
   int bytesRead = 0;
 
   TDEABC::AddresseeList list;
@@ -71,7 +71,7 @@ TDEABC::AddresseeList EudoraXXPort::importContacts( const TQString& ) const
       if ( a ) { // Write it out
         list << *a;
         delete a;
-        a = 0;
+        a = nullptr;
         a = new TDEABC::Addressee();
       } else
         a = new TDEABC::Addressee();
@@ -112,7 +112,7 @@ TDEABC::AddresseeList EudoraXXPort::importContacts( const TQString& ) const
   if ( a ) { // Write out address
     list << *a;
     delete a;
-    a = 0;
+    a = nullptr;
   }
 
   file.close();
diff --git a/kaddressbook/xxport/eudora_xxport.h b/kaddressbook/xxport/eudora_xxport.h
index 1f6007f51..6517b4cc4 100644
--- a/kaddressbook/xxport/eudora_xxport.h
+++ b/kaddressbook/xxport/eudora_xxport.h
@@ -32,7 +32,7 @@ class EudoraXXPort : public KAB::XXPort
   
 
   public:
-    EudoraXXPort( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = 0 );
+    EudoraXXPort( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = nullptr );
 
     TQString identifier() const { return "eudora"; }
 
diff --git a/kaddressbook/xxport/kde2_xxport.h b/kaddressbook/xxport/kde2_xxport.h
index 146fa1179..3ba1ea1e5 100644
--- a/kaddressbook/xxport/kde2_xxport.h
+++ b/kaddressbook/xxport/kde2_xxport.h
@@ -32,7 +32,7 @@ class KDE2XXPort : public KAB::XXPort
   
 
   public:
-    KDE2XXPort( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = 0 );
+    KDE2XXPort( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = nullptr );
 
     TQString identifier() const { return "kde2"; }
 
diff --git a/kaddressbook/xxport/ldif_xxport.cpp b/kaddressbook/xxport/ldif_xxport.cpp
index 8a68c481a..0217b6260 100644
--- a/kaddressbook/xxport/ldif_xxport.cpp
+++ b/kaddressbook/xxport/ldif_xxport.cpp
@@ -64,7 +64,7 @@ TDEABC::AddresseeList LDIFXXPort::importContacts( const TQString& ) const
   TDEABC::AddresseeList addrList;
 
   TQString fileName = KFileDialog::getOpenFileName( TQDir::homeDirPath(),
-                      "text/x-ldif", 0 );
+                      "text/x-ldif", nullptr );
   if ( fileName.isEmpty() )
     return addrList;
 
diff --git a/kaddressbook/xxport/ldif_xxport.h b/kaddressbook/xxport/ldif_xxport.h
index 11cbd40b3..2f91c19f2 100644
--- a/kaddressbook/xxport/ldif_xxport.h
+++ b/kaddressbook/xxport/ldif_xxport.h
@@ -33,7 +33,7 @@ class LDIFXXPort : public KAB::XXPort
   
 
   public:
-    LDIFXXPort( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = 0 );
+    LDIFXXPort( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = nullptr );
 
     TQString identifier() const { return "ldif"; }
 
diff --git a/kaddressbook/xxport/opera_xxport.h b/kaddressbook/xxport/opera_xxport.h
index e0723c58d..f785126f1 100644
--- a/kaddressbook/xxport/opera_xxport.h
+++ b/kaddressbook/xxport/opera_xxport.h
@@ -33,7 +33,7 @@ class OperaXXPort : public KAB::XXPort
   
 
   public:
-    OperaXXPort( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = 0 );
+    OperaXXPort( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = nullptr );
 
     TQString identifier() const { return "opera"; }
 
diff --git a/kaddressbook/xxport/pab_xxport.cpp b/kaddressbook/xxport/pab_xxport.cpp
index 4d890b377..9fa61424a 100644
--- a/kaddressbook/xxport/pab_xxport.cpp
+++ b/kaddressbook/xxport/pab_xxport.cpp
@@ -51,7 +51,7 @@ TDEABC::AddresseeList PABXXPort::importContacts( const TQString& ) const
   TDEABC::AddresseeList addrList;
 
   TQString fileName = KFileDialog::getOpenFileName( TQDir::homeDirPath(),
-      		"*.[pP][aA][bB]|" + i18n("MS Exchange Personal Address Book Files (*.pab)"), 0 );
+        "*.[pP][aA][bB]|" + i18n("MS Exchange Personal Address Book Files (*.pab)"), nullptr );
   if ( fileName.isEmpty() )
     return addrList;
   if ( !TQFile::exists( fileName ) ) {
diff --git a/kaddressbook/xxport/pab_xxport.h b/kaddressbook/xxport/pab_xxport.h
index b3b6fb299..e42068089 100644
--- a/kaddressbook/xxport/pab_xxport.h
+++ b/kaddressbook/xxport/pab_xxport.h
@@ -33,7 +33,7 @@ class PABXXPort : public KAB::XXPort
   
 
   public:
-    PABXXPort( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = 0 );
+    PABXXPort( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = nullptr );
 
     TQString identifier() const { return "pab"; }
 
diff --git a/kaddressbook/xxport/vcard_xxport.cpp b/kaddressbook/xxport/vcard_xxport.cpp
index 797c31d7d..d3488530c 100644
--- a/kaddressbook/xxport/vcard_xxport.cpp
+++ b/kaddressbook/xxport/vcard_xxport.cpp
@@ -56,7 +56,7 @@ class VCardViewerDialog : public KDialogBase
 {
   public:
     VCardViewerDialog( const TDEABC::Addressee::List &list,
-                       TQWidget *parent, const char *name = 0 );
+                       TQWidget *parent, const char *name = nullptr );
 
     TDEABC::Addressee::List contacts() const;
 
@@ -78,7 +78,7 @@ class VCardViewerDialog : public KDialogBase
 class VCardExportSelectionDialog : public KDialogBase
 {
   public:
-    VCardExportSelectionDialog( TQWidget *parent, const char *name = 0 );
+    VCardExportSelectionDialog( TQWidget *parent, const char *name = nullptr );
     ~VCardExportSelectionDialog();
 
     bool exportPrivateFields() const;
diff --git a/kaddressbook/xxport/vcard_xxport.h b/kaddressbook/xxport/vcard_xxport.h
index 780d7ccc0..45c897908 100644
--- a/kaddressbook/xxport/vcard_xxport.h
+++ b/kaddressbook/xxport/vcard_xxport.h
@@ -33,7 +33,7 @@ class VCardXXPort : public KAB::XXPort
   
 
   public:
-    VCardXXPort( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = 0 );
+    VCardXXPort( TDEABC::AddressBook *ab, TQWidget *parent, const char *name = nullptr );
 
     TQString identifier() const { return "vcard"; }
 
diff --git a/kaddressbook/xxportmanager.h b/kaddressbook/xxportmanager.h
index 58cbcb754..595183a78 100644
--- a/kaddressbook/xxportmanager.h
+++ b/kaddressbook/xxportmanager.h
@@ -43,7 +43,7 @@ class TDE_EXPORT XXPortManager : public TQObject
   
 
   public:
-    XXPortManager( KAB::Core *core, TQObject *parent, const char *name = 0 );
+    XXPortManager( KAB::Core *core, TQObject *parent, const char *name = nullptr );
     ~XXPortManager();
 
     void restoreSettings();
diff --git a/kaddressbook/xxportselectdialog.h b/kaddressbook/xxportselectdialog.h
index 725dfd22b..1f0039081 100644
--- a/kaddressbook/xxportselectdialog.h
+++ b/kaddressbook/xxportselectdialog.h
@@ -49,7 +49,7 @@ class XXPortSelectDialog : public KDialogBase
 
   public:
     XXPortSelectDialog( KAB::Core *core, bool sort, TQWidget* parent,
-                        const char* name = 0 );
+                        const char* name = nullptr );
 
     TDEABC::AddresseeList contacts();
 
diff --git a/libkpimidentities/identity.cpp b/libkpimidentities/identity.cpp
index f81bc3b15..98476c398 100644
--- a/libkpimidentities/identity.cpp
+++ b/libkpimidentities/identity.cpp
@@ -102,7 +102,7 @@ TQString Signature::textFromCommand( bool * ok ) const
     if ( ok ) *ok = false;
     TQString wmsg = i18n("<qt>Failed to execute signature script<br><b>%1</b>:<br>%2</qt>")
       .arg( mUrl ).arg( strerror(rc) );
-    KMessageBox::error(0, wmsg);
+    KMessageBox::error(nullptr, wmsg);
     return TQString();
   }
 
@@ -225,7 +225,7 @@ TQDataStream & KPIM::operator>>( TQDataStream & stream, KPIM::Signature & sig )
 }
 
 // ### should use a kstaticdeleter?
-static Identity* identityNull = 0;
+static Identity* identityNull = nullptr;
 const Identity& Identity::null()
 {
     if ( !identityNull )
diff --git a/libkpimidentities/identity.h b/libkpimidentities/identity.h
index bdc313855..947341f04 100644
--- a/libkpimidentities/identity.h
+++ b/libkpimidentities/identity.h
@@ -57,11 +57,11 @@ public:
   Signature( const TQString & url, bool isExecutable );
 
   /** @return the raw signature text as entered resp. read from file. */
-  TQString rawText( bool * ok=0 ) const;
+  TQString rawText( bool * ok=nullptr ) const;
 
   /** @return the signature text with a "-- " separator added, if
       necessary. */
-  TQString withSeparator( bool * ok=0 ) const;
+  TQString withSeparator( bool * ok=nullptr ) const;
 
   /** Set the signature text and mark this signature as being of
       "inline text" type. */
@@ -271,7 +271,7 @@ public:
     correct. So use this method to rectreive the contents of the
     signature file. If @p prompt is false, no errors will be displayed
     (useful for retries). */
-  TQString signatureText( bool * ok=0) const;
+  TQString signatureText( bool * ok=nullptr) const;
 
   /** The transport that is set for this identity. Used to link a
       transport with an identity. */
diff --git a/libkpimidentities/identitycombo.h b/libkpimidentities/identitycombo.h
index 5b780b9ab..6314d2ad5 100644
--- a/libkpimidentities/identitycombo.h
+++ b/libkpimidentities/identitycombo.h
@@ -52,7 +52,7 @@ class TDE_EXPORT IdentityCombo : public TQComboBox {
   TQ_OBJECT
   
 public:
-  IdentityCombo( IdentityManager* manager, TQWidget * parent=0, const char * name=0 );
+  IdentityCombo( IdentityManager* manager, TQWidget * parent=nullptr, const char * name=nullptr );
 
   TQString currentIdentityName() const;
   uint currentIdentity() const;
diff --git a/libkpimidentities/identitymanager.h b/libkpimidentities/identitymanager.h
index 69a18f508..29f92ba5c 100644
--- a/libkpimidentities/identitymanager.h
+++ b/libkpimidentities/identitymanager.h
@@ -66,7 +66,7 @@ public:
    * This means in particular that if there is no identity configured,
    * the default identity created here will not be saved.
    */
-  IdentityManager( bool readonly = false, TQObject * parent=0, const char * name=0 );
+  IdentityManager( bool readonly = false, TQObject * parent=nullptr, const char * name=nullptr );
   virtual ~IdentityManager();
 
 public:
diff --git a/tdeabc/tdeabc2mutt/main.cpp b/tdeabc/tdeabc2mutt/main.cpp
index 0d9635c27..724b664e4 100644
--- a/tdeabc/tdeabc2mutt/main.cpp
+++ b/tdeabc/tdeabc2mutt/main.cpp
@@ -32,11 +32,11 @@ static const char description[] = I18N_NOOP( "tdeabc - mutt converter" );
 
 static TDECmdLineOptions k2moptions[] =
 {
-  { "query <substring>", I18N_NOOP( "Only show contacts where name or address matches <substring>" ), 0 },
+  { "query <substring>", I18N_NOOP( "Only show contacts where name or address matches <substring>" ), nullptr },
   { "format <format>", I18N_NOOP( "Default format is 'alias'. 'query' returns email<tab>name<tab>, as needed by mutt's query_command" ), "alias" },
-  { "alternate-key-format", I18N_NOOP( "Default key format is 'JohDoe', this option turns it into 'jdoe'" ), 0 },
-  { "ignore-case", I18N_NOOP( "Make queries case insensitive" ), 0 },
-  { "all-addresses", I18N_NOOP( "Return all mail addresses, not just the preferred one" ), 0},
+  { "alternate-key-format", I18N_NOOP( "Default key format is 'JohDoe', this option turns it into 'jdoe'" ), nullptr },
+  { "ignore-case", I18N_NOOP( "Make queries case insensitive" ), nullptr },
+  { "all-addresses", I18N_NOOP( "Return all mail addresses, not just the preferred one" ), nullptr},
   TDECmdLineLastOption
 };
 
@@ -51,7 +51,7 @@ int main( int argc, char **argv )
 
   TDECmdLineArgs *args = TDECmdLineArgs::parsedArgs();
 
-  KABC2Mutt *object = new KABC2Mutt( 0 );
+  KABC2Mutt *object = new KABC2Mutt( nullptr );
 
   // Handle --format option
   object->setFormat( (args->getOption("format") == "query") ? KABC2Mutt::Query : KABC2Mutt::Aliases );
diff --git a/tdeabc/tdeabc2mutt/tdeabc2mutt.cpp b/tdeabc/tdeabc2mutt/tdeabc2mutt.cpp
index f872a13c3..5dbae72cb 100644
--- a/tdeabc/tdeabc2mutt/tdeabc2mutt.cpp
+++ b/tdeabc/tdeabc2mutt/tdeabc2mutt.cpp
@@ -33,7 +33,7 @@ KABC2Mutt::KABC2Mutt( TQObject *parent, const char *name )
   : TQObject( parent, name ), mFormat( Aliases ),
     mIgnoreCase( false ), mAllAddresses( false ),
     mAlternateKeyFormat( false ),
-    mAddressBook( 0 )
+    mAddressBook( nullptr )
 {
 }
 
diff --git a/tdeabc/tdeabc2mutt/tdeabc2mutt.h b/tdeabc/tdeabc2mutt/tdeabc2mutt.h
index 6c9960c71..9a7f63866 100644
--- a/tdeabc/tdeabc2mutt/tdeabc2mutt.h
+++ b/tdeabc/tdeabc2mutt/tdeabc2mutt.h
@@ -31,7 +31,7 @@ class KABC2Mutt : public TQObject
 
     enum Format { Aliases, Query };
 
-    KABC2Mutt( TQObject *parent, const char *name = 0 );
+    KABC2Mutt( TQObject *parent, const char *name = nullptr );
 
     void setQuery( const TQString &query ) { mQuery = query; }
     void setFormat( Format format ) { mFormat = format; }
diff --git a/tdeabc/tdeabcdistlistupdater/tdeabcdistlistupdater.cpp b/tdeabc/tdeabcdistlistupdater/tdeabcdistlistupdater.cpp
index 059c64250..968286bd6 100644
--- a/tdeabc/tdeabcdistlistupdater/tdeabcdistlistupdater.cpp
+++ b/tdeabc/tdeabcdistlistupdater/tdeabcdistlistupdater.cpp
@@ -32,7 +32,7 @@
 
 static const TDECmdLineOptions options[] =
 {
-  { "disable-autostart", "Disable automatic startup on login", 0 },
+  { "disable-autostart", "Disable automatic startup on login", nullptr },
   TDECmdLineLastOption
 };
 
@@ -73,7 +73,7 @@ int main( int argc, char **argv )
   TDEApplication::disableAutoDcopRegistration();
 
   TDEAboutData aboutData( "tdeabcdistlistupdater", "Converter tool for distribution lists", "0.1" );
-  aboutData.addAuthor( "Tobias Koenig", 0, "tokoe@kde.org" );
+  aboutData.addAuthor( "Tobias Koenig", nullptr, "tokoe@kde.org" );
 
   TDECmdLineArgs::init( argc, argv, &aboutData );
   TDECmdLineArgs::addCmdLineOptions( options );
-- 
cgit v1.2.3

