Doc: replace QItemDelegate with QStyledItemDelegate

Since QStyledItemDelegate should be preferred over QItemDelegate the
documentation should point to QStyledItemDelegate instead.
Also mark some internal classes which derive from QItemDelegate so they
will not be forgotten during Qt6 porting.

Change-Id: I2dd17feedf8593afac5ca16d2546e1f0bc0250ae
Reviewed-by: Paul Wicking <paul.wicking@qt.io>
Reviewed-by: Konstantin Shegunov <kshegunov@gmail.com>
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@qt.io>

src/sql/models/qsqlrelationaldelegate.h

@@ -58,7 +58,7 @@ QT_REQUIRE_CONFIG(sqlmodel);
 #include <QtCore/qmetaobject.h>
 QT_BEGIN_NAMESPACE
 
-
+// ### Qt6: QStyledItemDelegate
 class QSqlRelationalDelegate: public QItemDelegate
 {
     static int fieldIndex(const QSqlTableModel *const model,

src/widgets/doc/src/model-view-programming.qdoc

@@ -693,9 +693,9 @@
     \l QAbstractItemDelegate class.
 
     Delegates are expected to be able to render their contents themselves
-    by implementing the \l{QItemDelegate::paint()}{paint()}
+    by implementing the \l{QStyledItemDelegate::paint()}{paint()}
-    and \l{QItemDelegate::sizeHint()}{sizeHint()} functions.
+    and \l{QStyledItemDelegate::sizeHint()}{sizeHint()} functions.
-    However, simple widget-based delegates can subclass \l QItemDelegate
+    However, simple widget-based delegates can subclass \l QStyledItemDelegate
     instead of \l QAbstractItemDelegate, and take advantage of the default
     implementations of these functions.
 
@@ -709,14 +709,14 @@
 
     \section2 Using an existing delegate
 
-    The standard views provided with Qt use instances of \l QItemDelegate
+    The standard views provided with Qt use instances of \l QStyledItemDelegate
     to provide editing facilities. This default implementation of the
     delegate interface renders items in the usual style for each of the
     standard views: \l QListView, \l QTableView, and \l QTreeView.
 
     All the standard roles are handled by the default delegate used by
     the standard views. The way these are interpreted is described in the
-    QItemDelegate documentation.
+    QStyledItemDelegate documentation.
 
     The delegate used by a view is returned by the
     \l{QAbstractItemView::itemDelegate()}{itemDelegate()} function.
@@ -799,7 +799,7 @@
     In this case, we ensure that the spin box is up-to-date, and update
     the model with the value it contains using the index specified.
 
-    The standard \l QItemDelegate class informs the view when it has
+    The standard \l QStyledItemDelegate class informs the view when it has
     finished editing by emitting the
     \l{QAbstractItemDelegate::closeEditor()}{closeEditor()} signal.
     The view ensures that the editor widget is closed and destroyed. In
@@ -838,11 +838,11 @@
     assist any subsequent editing operations. This is achieved by
     emitting the \l{QAbstractItemDelegate::closeEditor()}{closeEditor()}
     signal with a suitable hint. This is taken care of by the default
-    QItemDelegate event filter which we installed on the spin box when
+    QStyledItemDelegate event filter which we installed on the spin box when
     it was constructed.
 
     The behavior of the spin box could be adjusted to make it more user
-    friendly. In the default event filter supplied by QItemDelegate, if
+    friendly. In the default event filter supplied by QStyledItemDelegate, if
     the user hits \uicontrol Return to confirm their choice in the spin box,
     the delegate commits the value to the model and closes the spin box.
     We can change this behavior by installing our own event filter on the

src/widgets/itemviews/qabstractitemdelegate.cpp

@@ -88,7 +88,7 @@ QT_BEGIN_NAMESPACE
     and is part of Qt's \l{Model/View Programming}{model/view framework}.
 
     To render an item in a custom way, you must implement paint() and
-    sizeHint(). The QItemDelegate class provides default implementations for
+    sizeHint(). The QStyledItemDelegate class provides default implementations for
     these functions; if you do not need custom rendering, subclass that
     class instead.
 
@@ -115,7 +115,7 @@ QT_BEGIN_NAMESPACE
     The second approach is to handle user events directly by reimplementing
     editorEvent().
 
-    \sa {model-view-programming}{Model/View Programming}, QItemDelegate,
+    \sa {model-view-programming}{Model/View Programming}, QStyledItemDelegate,
         {Pixelator Example}, QStyledItemDelegate, QStyle
 */
 

src/widgets/itemviews/qabstractitemview.cpp

@@ -3211,7 +3211,7 @@ bool QAbstractItemView::isPersistentEditorOpen(const QModelIndex &index) const
     This function should only be used to display static content within the
     visible area corresponding to an item of data. If you want to display
     custom dynamic content or implement a custom editor widget, subclass
-    QItemDelegate instead.
+    QStyledItemDelegate instead.
 
     \sa {Delegate Classes}
 */

src/widgets/itemviews/qcolumnview_p.h

@@ -181,6 +181,7 @@ public:
 /*!
  * This is a delegate that will paint the triangle
  */
+// ### Qt6: QStyledItemDelegate
 class QColumnViewDelegate : public QItemDelegate
 {
 

src/widgets/itemviews/qdatawidgetmapper.cpp

@@ -324,6 +324,7 @@ void QDataWidgetMapperPrivate::_q_modelDestroyed()
 QDataWidgetMapper::QDataWidgetMapper(QObject *parent)
     : QObject(*new QDataWidgetMapperPrivate, parent)
 {
+    // ### Qt6: QStyledItemDelegate
     setItemDelegate(new QItemDelegate(this));
 }
 

src/widgets/itemviews/qitemeditorfactory.cpp

@@ -122,7 +122,7 @@ Q_SIGNALS:
     \inmodule QtWidgets
 
     When editing data in an item view, editors are created and
-    displayed by a delegate. QItemDelegate, which is the delegate by
+    displayed by a delegate. QStyledItemDelegate, which is the delegate by
     default installed on Qt's item views, uses a QItemEditorFactory to
     create editors for it. A default unique instance provided by
     QItemEditorFactory is used by all item delegates.  If you set a
@@ -156,7 +156,7 @@ Q_SIGNALS:
 
     Additional editors can be registered with the registerEditor() function.
 
-    \sa QItemDelegate, {Model/View Programming}, {Color Editor Factory Example}
+    \sa QStyledItemDelegate, {Model/View Programming}, {Color Editor Factory Example}
 */
 
 /*!
@@ -375,7 +375,7 @@ void QItemEditorFactory::setDefaultFactory(QItemEditorFactory *factory)
     QItemEditorCreatorBase objects are specialized widget factories that
     provide editor widgets for one particular QVariant data type. They
     are used by QItemEditorFactory to create editors for
-    \l{QItemDelegate}s. Creator bases must be registered with
+    \l{QStyledItemDelegate}s. Creator bases must be registered with
     QItemEditorFactory::registerEditor().
 
     An editor should provide a user property for the data it edits.
@@ -457,7 +457,7 @@ QItemEditorCreatorBase::~QItemEditorCreatorBase()
     \snippet code/src_gui_itemviews_qitemeditorfactory.cpp 1
 
     The constructor takes the name of the property that contains the
-    editing data. QItemDelegate can then access the property by name
+    editing data. QStyledItemDelegate can then access the property by name
     when it sets and retrieves editing data. Only use this class if
     your editor does not define a user property (using the USER
     keyword in the Q_PROPERTY macro).  If the widget has a user
@@ -472,7 +472,7 @@ QItemEditorCreatorBase::~QItemEditorCreatorBase()
 
     Constructs an editor creator object using \a valuePropertyName
     as the name of the property to be used for editing. The
-    property name is used by QItemDelegate when setting and
+    property name is used by QStyledItemDelegate when setting and
     getting editor data.
 
     Note that the \a valuePropertyName is only used if the editor
@@ -508,11 +508,11 @@ QItemEditorCreatorBase::~QItemEditorCreatorBase()
     \snippet code/src_gui_itemviews_qitemeditorfactory.cpp 2
 
     Setting the \c editorFactory created above in an item delegate via
-    QItemDelegate::setItemEditorFactory() makes sure that all values of type
+    QStyledItemDelegate::setItemEditorFactory() makes sure that all values of type
     QVariant::DateTime will be edited in \c{MyFancyDateTimeEdit}.
 
     The editor must provide a user property that will contain the
-    editing data. The property is used by \l{QItemDelegate}s to set
+    editing data. The property is used by \l{QStyledItemDelegate}s to set
     and retrieve the data (using Qt's \l{Meta-Object
     System}{meta-object system}). You set the user property with
     the USER keyword:
@@ -520,7 +520,7 @@ QItemEditorCreatorBase::~QItemEditorCreatorBase()
     \snippet code/src_gui_itemviews_qitemeditorfactory.cpp 3
 
     \sa QItemEditorCreatorBase, QItemEditorCreator,
-        QItemEditorFactory, QItemDelegate, {Color Editor Factory Example}
+        QItemEditorFactory, QStyledItemDelegate, {Color Editor Factory Example}
 */
 
 /*!

src/widgets/itemviews/qlistwidget.cpp

@@ -1757,7 +1757,7 @@ QWidget *QListWidget::itemWidget(QListWidgetItem *item) const
 
     This function should only be used to display static content in the place of
     a list widget item. If you want to display custom dynamic content or
-    implement a custom editor widget, use QListView and subclass QItemDelegate
+    implement a custom editor widget, use QListView and subclass QStyledItemDelegate
     instead.
 
     \sa itemWidget(), removeItemWidget(), {Delegate Classes}

src/widgets/itemviews/qtableview.cpp

@@ -1108,7 +1108,7 @@ int QTableViewPrivate::heightHintForIndex(const QModelIndex &index, int hint, QS
     \l showGrid property.
 
     The items shown in a table view, like those in the other item views, are
-    rendered and edited using standard \l{QItemDelegate}{delegates}. However,
+    rendered and edited using standard \l{QStyledItemDelegate}{delegates}. However,
     for some tasks it is sometimes useful to be able to insert widgets in a
     table instead. Widgets are set for particular indexes with the
     \l{QAbstractItemView::}{setIndexWidget()} function, and

src/widgets/itemviews/qtreewidget.cpp

@@ -3101,7 +3101,7 @@ QWidget *QTreeWidget::itemWidget(QTreeWidgetItem *item, int column) const
 
     This function should only be used to display static content in the place of
     a tree widget item. If you want to display custom dynamic content or
-    implement a custom editor widget, use QTreeView and subclass QItemDelegate
+    implement a custom editor widget, use QTreeView and subclass QStyledItemDelegate
     instead.
 
     This function cannot be called before the item hierarchy has been set up,

src/widgets/util/qcompleter_p.h

@@ -194,6 +194,7 @@ private:
                      const QIndexMapper& iv, QMatchData* m);
 };
 
+// ### Qt6: QStyledItemDelegate
 class QCompleterItemDelegate : public QItemDelegate
 {
 public:

src/widgets/widgets/qcalendarwidget.cpp

@@ -1555,6 +1555,7 @@ void QCalendarView::mouseReleaseEvent(QMouseEvent *event)
     }
 }
 
+// ### Qt6: QStyledItemDelegate
 class QCalendarDelegate : public QItemDelegate
 {
     Q_OBJECT

src/widgets/widgets/qcombobox_p.h

@@ -293,6 +293,7 @@ private:
     QComboBox *mCombo;
 };
 
+// ### Qt6: QStyledItemDelegate ?
 // Note that this class is intentionally not using QStyledItemDelegate
 // Vista does not use the new theme for combo boxes and there might
 // be other side effects from using the new class