- Qt 6.11
- Qt Widgets
- C++ Classes
- QAbstractItemView
- Qt 6.11.1 Reference Documentation

# QAbstractItemView Class

The QAbstractItemView class provides the basic functionality for item view classes. More...

Header: | `#include <QAbstractItemView>`
CMake: | `find_package(Qt6 REQUIRED COMPONENTS Widgets)` `target_link_libraries(mytarget PRIVATE Qt6::Widgets)`
qmake: | `QT += widgets`
Inherits: | QAbstractScrollArea
Inherited By: | QColumnView, QHeaderView, QListView, QTableView, and QTreeView

- List of all members, including inherited members
- Deprecated members

## Public Types

enum | DragDropMode { NoDragDrop, DragOnly, DropOnly, DragDrop, InternalMove }
enum | EditTrigger { NoEditTriggers, CurrentChanged, DoubleClicked, SelectedClicked, EditKeyPressed, …, AllEditTriggers }
flags | EditTriggers
enum | ScrollHint { EnsureVisible, PositionAtTop, PositionAtBottom, PositionAtCenter }
enum | ScrollMode { ScrollPerItem, ScrollPerPixel }
enum | SelectionBehavior { SelectItems, SelectRows, SelectColumns }
enum | SelectionMode { SingleSelection, ContiguousSelection, ExtendedSelection, MultiSelection, NoSelection }

## Properties

alternatingRowColors : bool autoScroll : bool autoScrollMargin : int defaultDropAction : Qt::DropAction dragDropMode : DragDropMode dragDropOverwriteMode : bool dragEnabled : bool editTriggers : EditTriggers horizontalScrollMode : ScrollMode | iconSize : QSize `(since 6.11)` keyboardSearchFlags : Qt::MatchFlags selectionBehavior : SelectionBehavior selectionMode : SelectionMode showDropIndicator : bool tabKeyNavigation : bool textElideMode : Qt::TextElideMode `(since 6.9)` updateThreshold : int verticalScrollMode : ScrollMode

## Public Functions

| QAbstractItemView(QWidget *parent = nullptr)
virtual | ~QAbstractItemView()
bool | alternatingRowColors() const
int | autoScrollMargin() const
void | closePersistentEditor(const QModelIndex &index)
QModelIndex | currentIndex() const
Qt::DropAction | defaultDropAction() const
QAbstractItemView::DragDropMode | dragDropMode() const
bool | dragDropOverwriteMode() const
bool | dragEnabled() const
QAbstractItemView::EditTriggers | editTriggers() const
bool | hasAutoScroll() const
QAbstractItemView::ScrollMode | horizontalScrollMode() const
QSize | iconSize() const
virtual QModelIndex | indexAt(const QPoint &point) const = 0
QWidget * | indexWidget(const QModelIndex &index) const
bool | isPersistentEditorOpen(const QModelIndex &index) const
QAbstractItemDelegate * | itemDelegate() const
QAbstractItemDelegate * | itemDelegateForColumn(int column) const
`(since 6.0)` virtual QAbstractItemDelegate * | itemDelegateForIndex(const QModelIndex &index) const
QAbstractItemDelegate * | itemDelegateForRow(int row) const
virtual void | keyboardSearch(const QString &search)
Qt::MatchFlags | keyboardSearchFlags() const
QAbstractItemModel * | model() const
void | openPersistentEditor(const QModelIndex &index)
void | resetHorizontalScrollMode()
void | resetVerticalScrollMode()
QModelIndex | rootIndex() const
virtual void | scrollTo(const QModelIndex &index, QAbstractItemView::ScrollHint hint = EnsureVisible) = 0
QAbstractItemView::SelectionBehavior | selectionBehavior() const
QAbstractItemView::SelectionMode | selectionMode() const
QItemSelectionModel * | selectionModel() const
void | setAlternatingRowColors(bool enable)
void | setAutoScroll(bool enable)
void | setAutoScrollMargin(int margin)
void | setDefaultDropAction(Qt::DropAction dropAction)
void | setDragDropMode(QAbstractItemView::DragDropMode behavior)
void | setDragDropOverwriteMode(bool overwrite)
void | setDragEnabled(bool enable)
void | setDropIndicatorShown(bool enable)
void | setEditTriggers(QAbstractItemView::EditTriggers triggers)
void | setHorizontalScrollMode(QAbstractItemView::ScrollMode mode)
void | setIconSize(const QSize &size)
void | setIndexWidget(const QModelIndex &index, QWidget *widget)
void | setItemDelegate(QAbstractItemDelegate *delegate)
void | setItemDelegateForColumn(int column, QAbstractItemDelegate *delegate)
void | setItemDelegateForRow(int row, QAbstractItemDelegate *delegate)
void | setKeyboardSearchFlags(Qt::MatchFlags searchFlags)
virtual void | setModel(QAbstractItemModel *model)
void | setSelectionBehavior(QAbstractItemView::SelectionBehavior behavior)
void | setSelectionMode(QAbstractItemView::SelectionMode mode)
virtual void | setSelectionModel(QItemSelectionModel *selectionModel)
void | setTabKeyNavigation(bool enable)
void | setTextElideMode(Qt::TextElideMode mode)
void | setUpdateThreshold(int threshold)
void | setVerticalScrollMode(QAbstractItemView::ScrollMode mode)
bool | showDropIndicator() const
virtual int | sizeHintForColumn(int column) const
QSize | sizeHintForIndex(const QModelIndex &index) const
virtual int | sizeHintForRow(int row) const
bool | tabKeyNavigation() const
Qt::TextElideMode | textElideMode() const
int | updateThreshold() const
QAbstractItemView::ScrollMode | verticalScrollMode() const
virtual QRect | visualRect(const QModelIndex &index) const = 0

## Reimplemented Public Functions

virtual QVariant | inputMethodQuery(Qt::InputMethodQuery query) const override

## Public Slots

void | clearSelection()
void | edit(const QModelIndex &index)
virtual void | reset()
void | scrollToBottom()
void | scrollToTop()
virtual void | selectAll()
void | setCurrentIndex(const QModelIndex &index)
virtual void | setRootIndex(const QModelIndex &index)
void | update(const QModelIndex &index)

## Signals

void | activated(const QModelIndex &index)
void | clicked(const QModelIndex &index)
void | doubleClicked(const QModelIndex &index)
void | entered(const QModelIndex &index)
void | iconSizeChanged(const QSize &size)
void | pressed(const QModelIndex &index)
void | viewportEntered()

## Protected Types

enum | CursorAction { MoveUp, MoveDown, MoveLeft, MoveRight, MoveHome, …, MovePrevious }
enum | DropIndicatorPosition { OnItem, AboveItem, BelowItem, OnViewport }
enum | State { NoState, DraggingState, DragSelectingState, EditingState, ExpandingState, …, AnimatingState }

## Protected Functions

QPoint | dirtyRegionOffset() const
QAbstractItemView::DropIndicatorPosition | dropIndicatorPosition() const
virtual bool | edit(const QModelIndex &index, QAbstractItemView::EditTrigger trigger, QEvent *event)
void | executeDelayedItemsLayout()
virtual int | horizontalOffset() const = 0
`(since 6.0)` virtual void | initViewItemOption(QStyleOptionViewItem *option) const
virtual bool | isIndexHidden(const QModelIndex &index) const = 0
virtual QModelIndex | moveCursor(QAbstractItemView::CursorAction cursorAction, Qt::KeyboardModifiers modifiers) = 0
void | scheduleDelayedItemsLayout()
void | scrollDirtyRegion(int dx, int dy)
virtual QModelIndexList | selectedIndexes() const
virtual QItemSelectionModel::SelectionFlags | selectionCommand(const QModelIndex &index, const QEvent *event = nullptr) const
void | setDirtyRegion(const QRegion &region)
virtual void | setSelection(const QRect &rect, QItemSelectionModel::SelectionFlags flags) = 0
void | setState(QAbstractItemView::State state)
virtual void | startDrag(Qt::DropActions supportedActions)
QAbstractItemView::State | state() const
virtual int | verticalOffset() const = 0
virtual QRegion | visualRegionForSelection(const QItemSelection &selection) const = 0

## Reimplemented Protected Functions

virtual void | dragEnterEvent(QDragEnterEvent *event) override
virtual void | dragLeaveEvent(QDragLeaveEvent *event) override
virtual void | dragMoveEvent(QDragMoveEvent *event) override
virtual void | dropEvent(QDropEvent *event) override
virtual bool | event(QEvent *event) override
virtual bool | eventFilter(QObject *object, QEvent *event) override
virtual void | focusInEvent(QFocusEvent *event) override
virtual bool | focusNextPrevChild(bool next) override
virtual void | focusOutEvent(QFocusEvent *event) override
virtual void | inputMethodEvent(QInputMethodEvent *event) override
virtual void | keyPressEvent(QKeyEvent *event) override
virtual void | mouseDoubleClickEvent(QMouseEvent *event) override
virtual void | mouseMoveEvent(QMouseEvent *event) override
virtual void | mousePressEvent(QMouseEvent *event) override
virtual void | mouseReleaseEvent(QMouseEvent *event) override
virtual void | resizeEvent(QResizeEvent *event) override
virtual void | timerEvent(QTimerEvent *event) override
virtual bool | viewportEvent(QEvent *event) override
virtual QSize | viewportSizeHint() const override

## Protected Slots

virtual void | closeEditor(QWidget *editor, QAbstractItemDelegate::EndEditHint hint)
virtual void | commitData(QWidget *editor)
virtual void | currentChanged(const QModelIndex &current, const QModelIndex &previous)
virtual void | dataChanged(const QModelIndex &topLeft, const QModelIndex &bottomRight, const QList<int> &roles = QList<int>())
virtual void | editorDestroyed(QObject *editor)
virtual void | rowsAboutToBeRemoved(const QModelIndex &parent, int start, int end)
virtual void | rowsInserted(const QModelIndex &parent, int start, int end)
virtual void | selectionChanged(const QItemSelection &selected, const QItemSelection &deselected)
virtual void | updateGeometries()

## Detailed Description

QAbstractItemView class is the base class for every standard view that uses a QAbstractItemModel. QAbstractItemView is an abstract class and cannot itself be instantiated. It provides a standard interface for interoperating with models through the signals and slots mechanism, enabling subclasses to be kept up-to-date with changes to their models. This class provides standard support for keyboard and mouse navigation, viewport scrolling, item editing, and selections. The keyboard navigation implements this functionality:

Keys | Functionality
--- | ---
Arrow keys | Changes the current item and selects it.
Ctrl+Arrow keys | Changes the current item but does not select it.
Shift+Arrow keys | Changes the current item and selects it. The previously selected item(s) is not deselected.
Ctrl+Space | Toggles selection of the current item.
Tab/Backtab | Changes the current item to the next/previous item.
Home/End | Selects the first/last item in the model.
Page up/Page down | Scrolls the rows shown up/down by the number of visible rows in the view.
Ctrl+A | Selects all items in the model.

Note that the above table assumes that the selection mode allows the operations. For instance, you cannot select items if the selection mode is QAbstractItemView::NoSelection.

The QAbstractItemView class is one of the Model/View Classes and is part of Qt's model/view framework.

The view classes that inherit QAbstractItemView only need to implement their own view-specific functionality, such as drawing items, returning the geometry of items, finding items, etc.

QAbstractItemView provides common slots such as edit() and setCurrentIndex(). Many protected slots are also provided, including dataChanged(), rowsInserted(), rowsAboutToBeRemoved(), selectionChanged(), and currentChanged().

The root item is returned by rootIndex(), and the current item by currentIndex(). To make sure that an item is visible use scrollTo().

Some of QAbstractItemView's functions are concerned with scrolling, for example setHorizontalScrollMode() and setVerticalScrollMode(). To set the range of the scroll bars, you can, for example, reimplement the view's resizeEvent() function:

     void MyView::resizeEvent(QResizeEvent *event) {
         horizontalScrollBar()->setRange(0, realWidth - width());
         ...
     }

Note that the range is not updated until the widget is shown.

Several other functions are concerned with selection control; for example setSelectionMode(), and setSelectionBehavior(). This class provides a default selection model to work with (selectionModel()), but this can be replaced by using setSelectionModel() with an instance of QItemSelectionModel.

For complete control over the display and editing of items you can specify a delegate with setItemDelegate().

QAbstractItemView provides a lot of protected functions. Some are concerned with editing, for example, edit(), and commitData(), whilst others are keyboard and mouse event handlers.

Note: If you inherit QAbstractItemView and intend to update the contents of the viewport, you should use viewport->update() instead of update() as all painting operations take place on the viewport.

See also View Classes, Model/View Programming, and QAbstractItemModel.

## Member Type Documentation

### enum QAbstractItemView::CursorAction

This enum describes the different ways to navigate between items,

Constant | Value | Description
--- | --- | ---
`QAbstractItemView::MoveUp` | `0` | Move to the item above the current item.
`QAbstractItemView::MoveDown` | `1` | Move to the item below the current item.
`QAbstractItemView::MoveLeft` | `2` | Move to the item left of the current item.
`QAbstractItemView::MoveRight` | `3` | Move to the item right of the current item.
`QAbstractItemView::MoveHome` | `4` | Move to the top-left corner item.
`QAbstractItemView::MoveEnd` | `5` | Move to the bottom-right corner item.
`QAbstractItemView::MovePageUp` | `6` | Move one page up above the current item.
`QAbstractItemView::MovePageDown` | `7` | Move one page down below the current item.
`QAbstractItemView::MoveNext` | `8` | Move to the item after the current item.
`QAbstractItemView::MovePrevious` | `9` | Move to the item before the current item.

See also moveCursor().

### enum QAbstractItemView::DragDropMode

Describes the various drag and drop events the view can act upon. By default the view does not support dragging or dropping (`NoDragDrop`).

Constant | Value | Description
--- | --- | ---
`QAbstractItemView::NoDragDrop` | `0` | Does not support dragging or dropping.
`QAbstractItemView::DragOnly` | `1` | The view supports dragging of its own items
`QAbstractItemView::DropOnly` | `2` | The view accepts drops
`QAbstractItemView::DragDrop` | `3` | The view supports both dragging and dropping
`QAbstractItemView::InternalMove` | `4` | The view accepts move (not copy) operations only from itself.

Note that the model used needs to provide support for drag and drop operations.

See also setDragDropMode() and Using drag and drop with item views.

### enum QAbstractItemView::DropIndicatorPosition

This enum indicates the position of the drop indicator in relation to the index at the current mouse position:

Constant | Value | Description
--- | --- | ---
`QAbstractItemView::OnItem` | `0` | The item will be dropped on the index.
`QAbstractItemView::AboveItem` | `1` | The item will be dropped above the index.
`QAbstractItemView::BelowItem` | `2` | The item will be dropped below the index.
`QAbstractItemView::OnViewport` | `3` | The item will be dropped onto a region of the viewport with no items. The way each view handles items dropped onto the viewport depends on the behavior of the underlying model in use.

### enum QAbstractItemView::EditTrigger
flags QAbstractItemView::EditTriggers

This enum describes actions which will initiate item editing.

Constant | Value | Description
--- | --- | ---
`QAbstractItemView::NoEditTriggers` | `0` | No editing possible.
`QAbstractItemView::CurrentChanged` | `1` | Editing start whenever current item changes.
`QAbstractItemView::DoubleClicked` | `2` | Editing starts when an item is double clicked.
`QAbstractItemView::SelectedClicked` | `4` | Editing starts when clicking on an already selected item.
`QAbstractItemView::EditKeyPressed` | `8` | Editing starts when the platform edit key has been pressed over an item.
`QAbstractItemView::AnyKeyPressed` | `16` | Editing starts when any key is pressed over an item.
`QAbstractItemView::AllEditTriggers` | `31` | Editing starts for all above actions.

The EditTriggers type is a typedef for QFlags<EditTrigger>. It stores an OR combination of EditTrigger values.

### enum QAbstractItemView::ScrollHint

Constant | Value | Description
--- | --- | ---
`QAbstractItemView::EnsureVisible` | `0` | Scroll to ensure that the item is visible.
`QAbstractItemView::PositionAtTop` | `1` | Scroll to position the item at the top of the viewport.
`QAbstractItemView::PositionAtBottom` | `2` | Scroll to position the item at the bottom of the viewport.
`QAbstractItemView::PositionAtCenter` | `3` | Scroll to position the item at the center of the viewport.

### enum QAbstractItemView::ScrollMode

Describes how the scrollbar should behave. When setting the scroll mode to ScrollPerPixel the single step size will adjust automatically unless it was set explicitly using setSingleStep(). The automatic adjustment can be restored by setting the single step size to -1.

Constant | Value | Description
--- | --- | ---
`QAbstractItemView::ScrollPerItem` | `0` | The view will scroll the contents one item at a time.
`QAbstractItemView::ScrollPerPixel` | `1` | The view will scroll the contents one pixel at a time.

### enum QAbstractItemView::SelectionBehavior

Constant | Value | Description
--- | --- | ---
`QAbstractItemView::SelectItems` | `0` | Selecting single items.
`QAbstractItemView::SelectRows` | `1` | Selecting only rows.
`QAbstractItemView::SelectColumns` | `2` | Selecting only columns.

### enum QAbstractItemView::SelectionMode

This enum indicates how the view responds to user selections:

Constant | Value | Description
--- | --- | ---
`QAbstractItemView::SingleSelection` | `1` | When the user selects an item, any already-selected item becomes unselected. It is possible for the user to deselect the selected item by pressing the Ctrl key when clicking the selected item.
`QAbstractItemView::ContiguousSelection` | `4` | When the user selects an item in the usual way, the selection is cleared and the new item selected. However, if the user presses the Shift key while clicking on an item, all items between the current item and the clicked item are selected or unselected, depending on the state of the clicked item.
`QAbstractItemView::ExtendedSelection` | `3` | When the user selects an item in the usual way, the selection is cleared and the new item selected. However, if the user presses the Ctrl key when clicking on an item, the clicked item gets toggled and all other items are left untouched. If the user presses the Shift key while clicking on an item, all items between the current item and the clicked item are selected or unselected, depending on the state of the clicked item. Multiple items can be selected by dragging the mouse over them.
`QAbstractItemView::MultiSelection` | `2` | When the user selects an item in the usual way, the selection status of that item is toggled and the other items are left alone. Multiple items can be toggled by dragging the mouse over them.
`QAbstractItemView::NoSelection` | `0` | Items cannot be selected.

The most commonly used modes are SingleSelection and ExtendedSelection.

### enum QAbstractItemView::State

Describes the different states the view can be in. This is usually only interesting when reimplementing your own view.

Constant | Value | Description
--- | --- | ---
`QAbstractItemView::NoState` | `0` | The is the default state.
`QAbstractItemView::DraggingState` | `1` | The user is dragging items.
`QAbstractItemView::DragSelectingState` | `2` | The user is selecting items.
`QAbstractItemView::EditingState` | `3` | The user is editing an item in a widget editor.
`QAbstractItemView::ExpandingState` | `4` | The user is opening a branch of items.
`QAbstractItemView::CollapsingState` | `5` | The user is closing a branch of items.
`QAbstractItemView::AnimatingState` | `6` | The item view is performing an animation.

## Property Documentation

### alternatingRowColors : bool

This property holds whether to draw the background using alternating colors

If this property is `true`, the item background will be drawn using QPalette::Base and QPalette::AlternateBase; otherwise the background will be drawn using the QPalette::Base color.

By default, this property is `false`.

Access functions:

bool | alternatingRowColors() const
void | setAlternatingRowColors(bool enable)

### autoScroll : bool

This property holds whether autoscrolling in drag move events is enabled

If this property is set to true (the default), the QAbstractItemView automatically scrolls the contents of the view if the user drags within 16 pixels of the viewport edge. If the current item changes, then the view will scroll automatically to ensure that the current item is fully visible.

This property only works if the viewport accepts drops. Autoscroll is switched off by setting this property to false.

Access functions:

bool | hasAutoScroll() const
void | setAutoScroll(bool enable)

### autoScrollMargin : int

This property holds the size of the area when auto scrolling is triggered

This property controls the size of the area at the edge of the viewport that triggers autoscrolling. The default value is 16 pixels.

Access functions:

int | autoScrollMargin() const
void | setAutoScrollMargin(int margin)

### defaultDropAction : Qt::DropAction

This property holds the drop action that will be used by default in QAbstractItemView::drag().

If the property is not set, the drop action is CopyAction when the supported actions support CopyAction.

Access functions:

Qt::DropAction | defaultDropAction() const
void | setDefaultDropAction(Qt::DropAction dropAction)

See also showDropIndicator and dragDropOverwriteMode.

### dragDropMode : DragDropMode

This property holds the drag and drop event the view will act upon

Access functions:

QAbstractItemView::DragDropMode | dragDropMode() const
void | setDragDropMode(QAbstractItemView::DragDropMode behavior)

See also showDropIndicator and dragDropOverwriteMode.

### dragDropOverwriteMode : bool

This property holds the view's drag and drop behavior

If its value is `true`, the selected data will overwrite the existing item data when dropped, while moving the data will clear the item. If its value is `false`, the selected data will be inserted as a new item when the data is dropped. When the data is moved, the item is removed as well.

The default value is `false`, as in the QListView and QTreeView subclasses. In the QTableView subclass, on the other hand, the property has been set to `true`.

Note: This is not intended to prevent overwriting of items. The model's implementation of flags() should do that by not returning Qt::ItemIsDropEnabled.

Access functions:

bool | dragDropOverwriteMode() const
void | setDragDropOverwriteMode(bool overwrite)

See also dragDropMode.

### dragEnabled : bool

This property holds whether the view supports dragging of its own items

Access functions:

bool | dragEnabled() const
void | setDragEnabled(bool enable)

See also showDropIndicator, DragDropMode, dragDropOverwriteMode, and acceptDrops.

### editTriggers : EditTriggers

This property holds which actions will initiate item editing

This property is a selection of flags defined by EditTrigger, combined using the OR operator. The view will only initiate the editing of an item if the action performed is set in this property.

The default value is:

- for QTableView: DoubleClicked|AnyKeyPressed
- for all other views: DoubleClicked|EditKeyPressed

Access functions:

QAbstractItemView::EditTriggers | editTriggers() const
void | setEditTriggers(QAbstractItemView::EditTriggers triggers)

### horizontalScrollMode : ScrollMode

how the view scrolls its contents in the horizontal direction

This property controls how the view scroll its contents horizontally. Scrolling can be done either per pixel or per item. Its default value comes from the style via the QStyle::SH_ItemView_ScrollMode style hint.

Access functions:

QAbstractItemView::ScrollMode | horizontalScrollMode() const
void | setHorizontalScrollMode(QAbstractItemView::ScrollMode mode)
void | resetHorizontalScrollMode()

### iconSize : QSize

This property holds the size of items' icons

Setting this property when the view is visible will cause the items to be laid out again.

Access functions:

QSize | iconSize() const
void | setIconSize(const QSize &size)

Notifier signal:

void | iconSizeChanged(const QSize &size)

### `[since 6.11]` keyboardSearchFlags : Qt::MatchFlags

This property determines how the default implementation of keyboardSearch() matches the given string against the model's data.

The default value is `Qt::MatchStartsWith|Qt::MatchWrap`.

This property was introduced in Qt 6.11.

Access functions:

Qt::MatchFlags | keyboardSearchFlags() const
void | setKeyboardSearchFlags(Qt::MatchFlags searchFlags)

See also keyboardSearch() and QAbstractItemModel::match().

### selectionBehavior : SelectionBehavior

This property holds which selection behavior the view uses

This property holds whether selections are done in terms of single items, rows or columns.

Access functions:

QAbstractItemView::SelectionBehavior | selectionBehavior() const
void | setSelectionBehavior(QAbstractItemView::SelectionBehavior behavior)

See also SelectionMode and SelectionBehavior.

### selectionMode : SelectionMode

This property holds which selection mode the view operates in

This property controls whether the user can select one or many items and, in many-item selections, whether the selection must be a continuous range of items.

Access functions:

QAbstractItemView::SelectionMode | selectionMode() const
void | setSelectionMode(QAbstractItemView::SelectionMode mode)

See also SelectionMode and SelectionBehavior.

### showDropIndicator : bool

This property holds whether the drop indicator is shown when dragging items and dropping.

Access functions:

bool | showDropIndicator() const
void | setDropIndicatorShown(bool enable)

See also dragEnabled, DragDropMode, dragDropOverwriteMode, and acceptDrops.

### tabKeyNavigation : bool

This property holds whether item navigation with tab and backtab is enabled.

Access functions:

bool | tabKeyNavigation() const
void | setTabKeyNavigation(bool enable)

### textElideMode : Qt::TextElideMode

This property holds the position of the "..." in elided text.

The default value for all item views is Qt::ElideRight.

Access functions:

Qt::TextElideMode | textElideMode() const
void | setTextElideMode(Qt::TextElideMode mode)

### `[since 6.9]` updateThreshold : int

This property holds the amount of changed indexes to directly trigger a full update of the view inside dataChanged().

The algorithm inside dataChanged() tries to minimize a full update of the view by calculating if the changed indexes are visible or not. For very large models, with a lot of large changes, this might take longer than the actual update so it's counter-productive. This property gives the ability to control the algorithm to skip the check and directly trigger a full update when the amount of changed indexes exceeds the given value.

The default value is 200.

This property was introduced in Qt 6.9.

Access functions:

int | updateThreshold() const
void | setUpdateThreshold(int threshold)

See also dataChanged().

### verticalScrollMode : ScrollMode

how the view scrolls its contents in the vertical direction

This property controls how the view scroll its contents vertically. Scrolling can be done either per pixel or per item. Its default value comes from the style via the QStyle::SH_ItemView_ScrollMode style hint.

Access functions:

QAbstractItemView::ScrollMode | verticalScrollMode() const
void | setVerticalScrollMode(QAbstractItemView::ScrollMode mode)
void | resetVerticalScrollMode()

## Member Function Documentation

### `[explicit]` QAbstractItemView::QAbstractItemView(QWidget *parent = nullptr)

Constructs an abstract item view with the given parent.

### `[virtual noexcept]` QAbstractItemView::~QAbstractItemView()

Destroys the view.

### `[signal]` void QAbstractItemView::activated(const QModelIndex &index)

This signal is emitted when the item specified by index is activated by the user. How to activate items depends on the platform; e.g., by single- or double-clicking the item, or by pressing the Return or Enter key when the item is current.

See also clicked(), doubleClicked(), entered(), and pressed().

### `[slot]` void QAbstractItemView::clearSelection()

Deselects all selected items. The current index will not be changed.

See also setSelection() and selectAll().

### `[signal]` void QAbstractItemView::clicked(const QModelIndex &index)

This signal is emitted when a mouse button is left-clicked. The item the mouse was clicked on is specified by index. The signal is only emitted when the index is valid.

See also activated(), doubleClicked(), entered(), and pressed().

### `[virtual protected slot]` void QAbstractItemView::closeEditor(QWidget *editor, QAbstractItemDelegate::EndEditHint hint)

Closes the given editor, and releases it. The hint is used to specify how the view should respond to the end of the editing operation. For example, the hint may indicate that the next item in the view should be opened for editing.

See also edit() and commitData().

### void QAbstractItemView::closePersistentEditor(const QModelIndex &index)

Closes the persistent editor for the item at the given index.

See also openPersistentEditor() and isPersistentEditorOpen().

### `[virtual protected slot]` void QAbstractItemView::commitData(QWidget *editor)

Commit the data in the editor to the model.

See also closeEditor().

### `[virtual protected slot]` void QAbstractItemView::currentChanged(const QModelIndex &current, const QModelIndex &previous)

This slot is called when a new item becomes the current item. The previous current item is specified by the previous index, and the new item by the current index.

If you want to know about changes to items see the dataChanged() signal.

### QModelIndex QAbstractItemView::currentIndex() const

Returns the model index of the current item.

See also setCurrentIndex().

### `[virtual protected slot]` void QAbstractItemView::dataChanged(const QModelIndex &topLeft, const QModelIndex &bottomRight, const QList<int> &roles = QList<int>())

This slot is called when items with the given roles are changed in the model. The changed items are those from topLeft to bottomRight inclusive. If just one item is changed topLeft == bottomRight.

The roles which have been changed can either be an empty container (meaning everything has changed), or a non-empty container with the subset of roles which have changed.

Note: : Qt::ToolTipRole is not honored by dataChanged() in the views provided by Qt.

### `[protected]` QPoint QAbstractItemView::dirtyRegionOffset() const

Returns the offset of the dirty regions in the view.

If you use scrollDirtyRegion() and implement a paintEvent() in a subclass of QAbstractItemView, you should translate the area given by the paint event with the offset returned from this function.

See also scrollDirtyRegion() and setDirtyRegion().

### `[signal]` void QAbstractItemView::doubleClicked(const QModelIndex &index)

This signal is emitted when a mouse button is double-clicked. The item the mouse was double-clicked on is specified by index. The signal is only emitted when the index is valid.

See also clicked() and activated().

### `[override virtual protected]` void QAbstractItemView::dragEnterEvent(QDragEnterEvent *event)

Reimplements: QAbstractScrollArea::dragEnterEvent(QDragEnterEvent *event).

This function is called with the given event when a drag and drop operation enters the widget. If the drag is over a valid dropping place (e.g. over an item that accepts drops), the event is accepted; otherwise it is ignored.

See also dropEvent() and startDrag().

### `[override virtual protected]` void QAbstractItemView::dragLeaveEvent(QDragLeaveEvent *event)

Reimplements: QAbstractScrollArea::dragLeaveEvent(QDragLeaveEvent *event).

This function is called when the item being dragged leaves the view. The event describes the state of the drag and drop operation.

### `[override virtual protected]` void QAbstractItemView::dragMoveEvent(QDragMoveEvent *event)

Reimplements: QAbstractScrollArea::dragMoveEvent(QDragMoveEvent *event).

This function is called continuously with the given event during a drag and drop operation over the widget. It can cause the view to scroll if, for example, the user drags a selection to view's right or bottom edge. In this case, the event will be accepted; otherwise it will be ignored.

See also dropEvent() and startDrag().

### `[override virtual protected]` void QAbstractItemView::dropEvent(QDropEvent *event)

Reimplements: QAbstractScrollArea::dropEvent(QDropEvent *event).

This function is called with the given event when a drop event occurs over the widget. If the model accepts the even position the drop event is accepted; otherwise it is ignored.

See also startDrag().

### `[protected]` QAbstractItemView::DropIndicatorPosition QAbstractItemView::dropIndicatorPosition() const

Returns the position of the drop indicator in relation to the closest item.

### `[slot]` void QAbstractItemView::edit(const QModelIndex &index)

Starts editing the item corresponding to the given index if it is editable.

Note that this function does not change the current index. Since the current index defines the next and previous items to edit, users may find that keyboard navigation does not work as expected. To provide consistent navigation behavior, call setCurrentIndex() before this function with the same model index.

Note: This slot is overloaded. To connect to this slot:

     // Connect using qOverload:
     connect(sender, &SenderClass::signal,
             abstractItemView, qOverload(&QAbstractItemView::edit));

     // Or using a lambda as wrapper:
     connect(sender, &SenderClass::signal,
             abstractItemView, [receiver = abstractItemView](const QModelIndex &index) { receiver->edit(index); });

For more examples and approaches, see connecting to overloaded slots.

See also QModelIndex::flags().

### `[virtual protected]` bool QAbstractItemView::edit(const QModelIndex &index, QAbstractItemView::EditTrigger trigger, QEvent *event)

Starts editing the item at index, creating an editor if necessary, and returns `true` if the view's State is now EditingState; otherwise returns `false`.

The action that caused the editing process is described by trigger, and the associated event is specified by event.

Editing can be forced by specifying the trigger to be QAbstractItemView::AllEditTriggers.

See also closeEditor().

### `[virtual protected slot]` void QAbstractItemView::editorDestroyed(QObject *editor)

This function is called when the given editor has been destroyed.

See also closeEditor().

### `[signal]` void QAbstractItemView::entered(const QModelIndex &index)

This signal is emitted when the mouse cursor enters the item specified by index. Mouse tracking needs to be enabled for this feature to work.

See also viewportEntered(), activated(), clicked(), doubleClicked(), and pressed().

### `[override virtual protected]` bool QAbstractItemView::event(QEvent *event)

Reimplements: QAbstractScrollArea::event(QEvent *event).

### `[override virtual protected]` bool QAbstractItemView::eventFilter(QObject *object, QEvent *event)

Reimplements: QObject::eventFilter(QObject *watched, QEvent *event).

### `[protected]` void QAbstractItemView::executeDelayedItemsLayout()

Executes the scheduled layouts without waiting for the event processing to begin.

See also scheduleDelayedItemsLayout().

### `[override virtual protected]` void QAbstractItemView::focusInEvent(QFocusEvent *event)

Reimplements: QWidget::focusInEvent(QFocusEvent *event).

This function is called with the given event when the widget obtains the focus. By default, the event is ignored.

See also setFocus() and focusOutEvent().

### `[override virtual protected]` bool QAbstractItemView::focusNextPrevChild(bool next)

Reimplements: QWidget::focusNextPrevChild(bool next).

### `[override virtual protected]` void QAbstractItemView::focusOutEvent(QFocusEvent *event)

Reimplements: QWidget::focusOutEvent(QFocusEvent *event).

This function is called with the given event when the widget loses the focus. By default, the event is ignored.

See also clearFocus() and focusInEvent().

### `[pure virtual protected]` int QAbstractItemView::horizontalOffset() const

Returns the horizontal offset of the view.

In the base class this is a pure virtual function.

See also verticalOffset().

### `[pure virtual]` QModelIndex QAbstractItemView::indexAt(const QPoint &point) const

Returns the model index of the item at the viewport coordinates point.

In the base class this is a pure virtual function.

See also visualRect().

### QWidget *QAbstractItemView::indexWidget(const QModelIndex &index) const

Returns the widget for the item at the given index.

See also setIndexWidget().

### `[virtual protected, since 6.0]` void QAbstractItemView::initViewItemOption(QStyleOptionViewItem *option) const

Initialize the option structure with the view's palette, font, state, alignments etc.

Note: Implementations of this methods should check the version of the structure received, populate all members the implementation is familiar with, and set the version member to the one supported by the implementation before returning.

This function was introduced in Qt 6.0.

### `[override virtual protected]` void QAbstractItemView::inputMethodEvent(QInputMethodEvent *event)

Reimplements: QWidget::inputMethodEvent(QInputMethodEvent *event).

### `[override virtual]` QVariant QAbstractItemView::inputMethodQuery(Qt::InputMethodQuery query) const

Reimplements: QWidget::inputMethodQuery(Qt::InputMethodQuery query) const.

### `[pure virtual protected]` bool QAbstractItemView::isIndexHidden(const QModelIndex &index) const

Returns `true` if the item referred to by the given index is hidden in the view, otherwise returns `false`.

Hiding is a view specific feature. For example in TableView a column can be marked as hidden or a row in the TreeView.

In the base class this is a pure virtual function.

### bool QAbstractItemView::isPersistentEditorOpen(const QModelIndex &index) const

Returns whether a persistent editor is open for the item at index index.

See also openPersistentEditor() and closePersistentEditor().

### QAbstractItemDelegate *QAbstractItemView::itemDelegate() const

Returns the item delegate used by this view and model. This is either one set with setItemDelegate(), or the default one.

See also setItemDelegate().

### QAbstractItemDelegate *QAbstractItemView::itemDelegateForColumn(int column) const

Returns the item delegate used by this view and model for the given column. You can call itemDelegate() to get a pointer to the current delegate for a given index.

See also setItemDelegateForColumn(), itemDelegateForRow(), and itemDelegate().

### `[virtual, since 6.0]` QAbstractItemDelegate *QAbstractItemView::itemDelegateForIndex(const QModelIndex &index) const

Returns the item delegate used by this view and model for the given index.

This function was introduced in Qt 6.0.

See also setItemDelegate(), setItemDelegateForRow(), and setItemDelegateForColumn().

### QAbstractItemDelegate *QAbstractItemView::itemDelegateForRow(int row) const

Returns the item delegate used by this view and model for the given row, or `nullptr` if no delegate has been assigned. You can call itemDelegate() to get a pointer to the current delegate for a given index.

See also setItemDelegateForRow(), itemDelegateForColumn(), and setItemDelegate().

### `[override virtual protected]` void QAbstractItemView::keyPressEvent(QKeyEvent *event)

Reimplements: QAbstractScrollArea::keyPressEvent(QKeyEvent *e).

This function is called with the given event when a key event is sent to the widget. The default implementation handles basic cursor movement, e.g. Up, Down, Left, Right, Home, PageUp, and PageDown; the activated() signal is emitted if the current index is valid and the activation key is pressed (e.g. Enter or Return, depending on the platform). This function is where editing is initiated by key press, e.g. if F2 is pressed.

See also edit(), moveCursor(), keyboardSearch(), and tabKeyNavigation.

### `[virtual]` void QAbstractItemView::keyboardSearch(const QString &search)

Moves to and selects the item best matching the string search. If no item is found nothing happens.

In the default implementation, the search is reset if search is empty, or the time interval since the last search has exceeded QApplication::keyboardInputInterval().

### QAbstractItemModel *QAbstractItemView::model() const

Returns the model that this view is presenting.

See also setModel().

### `[override virtual protected]` void QAbstractItemView::mouseDoubleClickEvent(QMouseEvent *event)

Reimplements: QAbstractScrollArea::mouseDoubleClickEvent(QMouseEvent *e).

This function is called with the given event when a mouse button is double clicked inside the widget. If the double-click is on a valid item it emits the doubleClicked() signal and calls edit() on the item.

### `[override virtual protected]` void QAbstractItemView::mouseMoveEvent(QMouseEvent *event)

Reimplements: QAbstractScrollArea::mouseMoveEvent(QMouseEvent *e).

This function is called with the given event when a mouse move event is sent to the widget. If a selection is in progress and new items are moved over the selection is extended; if a drag is in progress it is continued.

### `[override virtual protected]` void QAbstractItemView::mousePressEvent(QMouseEvent *event)

Reimplements: QAbstractScrollArea::mousePressEvent(QMouseEvent *e).

This function is called with the given event when a mouse button is pressed while the cursor is inside the widget. If a valid item is pressed on it is made into the current item. This function emits the pressed() signal.

### `[override virtual protected]` void QAbstractItemView::mouseReleaseEvent(QMouseEvent *event)

Reimplements: QAbstractScrollArea::mouseReleaseEvent(QMouseEvent *e).

This function is called with the given event when a mouse button is released, after a mouse press event on the widget. If a user presses the mouse inside your widget and then drags the mouse to another location before releasing the mouse button, your widget receives the release event. The function will emit the clicked() signal if an item was being pressed.

### `[pure virtual protected]` QModelIndex QAbstractItemView::moveCursor(QAbstractItemView::CursorAction cursorAction, Qt::KeyboardModifiers modifiers)

Returns a QModelIndex object pointing to the next object in the view, based on the given cursorAction and keyboard modifiers specified by modifiers.

In the base class this is a pure virtual function.

### void QAbstractItemView::openPersistentEditor(const QModelIndex &index)

Opens a persistent editor on the item at the given index. If no editor exists, the delegate will create a new editor.

See also closePersistentEditor() and isPersistentEditorOpen().

### `[signal]` void QAbstractItemView::pressed(const QModelIndex &index)

This signal is emitted when a mouse button is pressed. The item the mouse was pressed on is specified by index. The signal is only emitted when the index is valid.

Use the QGuiApplication::mouseButtons() function to get the state of the mouse buttons.

See also activated(), clicked(), doubleClicked(), and entered().

### `[virtual slot]` void QAbstractItemView::reset()

Reset the internal state of the view.

Warning: This function will reset open editors, scroll bar positions, selections, etc. Existing changes will not be committed. If you would like to save your changes when resetting the view, you can reimplement this function, commit your changes, and then call the superclass' implementation.

### `[override virtual protected]` void QAbstractItemView::resizeEvent(QResizeEvent *event)

Reimplements: QAbstractScrollArea::resizeEvent(QResizeEvent *event).

This function is called with the given event when a resize event is sent to the widget.

See also QWidget::resizeEvent().

### QModelIndex QAbstractItemView::rootIndex() const

Returns the model index of the model's root item. The root item is the parent item to the view's toplevel items. The root can be invalid.

See also setRootIndex().

### `[virtual protected slot]` void QAbstractItemView::rowsAboutToBeRemoved(const QModelIndex &parent, int start, int end)

This slot is called when rows are about to be removed. The deleted rows are those under the given parent from start to end inclusive.

See also rowsInserted().

### `[virtual protected slot]` void QAbstractItemView::rowsInserted(const QModelIndex &parent, int start, int end)

This slot is called when rows are inserted. The new rows are those under the given parent from start to end inclusive. The base class implementation calls fetchMore() on the model to check for more data.

See also rowsAboutToBeRemoved().

### `[protected]` void QAbstractItemView::scheduleDelayedItemsLayout()

Schedules a layout of the items in the view to be executed when the event processing starts.

Even if scheduleDelayedItemsLayout() is called multiple times before events are processed, the view will only do the layout once.

See also executeDelayedItemsLayout().

### `[protected]` void QAbstractItemView::scrollDirtyRegion(int dx, int dy)

Prepares the view for scrolling by (dx,dy) pixels by moving the dirty regions in the opposite direction. You only need to call this function if you are implementing a scrolling viewport in your view subclass.

If you implement scrollContentsBy() in a subclass of QAbstractItemView, call this function before you call QWidget::scroll() on the viewport. Alternatively, just call update().

See also scrollContentsBy(), dirtyRegionOffset(), and setDirtyRegion().

### `[pure virtual]` void QAbstractItemView::scrollTo(const QModelIndex &index, QAbstractItemView::ScrollHint hint = EnsureVisible)

Scrolls the view if necessary to ensure that the item at index is visible. The view will try to position the item according to the given hint.

In the base class this is a pure virtual function.

### `[slot]` void QAbstractItemView::scrollToBottom()

Scrolls the view to the bottom.

See also scrollTo() and scrollToTop().

### `[slot]` void QAbstractItemView::scrollToTop()

Scrolls the view to the top.

See also scrollTo() and scrollToBottom().

### `[virtual slot]` void QAbstractItemView::selectAll()

Selects all items in the view. This function will use the selection behavior set on the view when selecting.

See also setSelection(), selectedIndexes(), and clearSelection().

### `[virtual protected]` QModelIndexList QAbstractItemView::selectedIndexes() const

This convenience function returns a list of all selected and non-hidden item indexes in the view. The list contains no duplicates, and is not sorted.

See also QItemSelectionModel::selectedIndexes().

### `[virtual protected slot]` void QAbstractItemView::selectionChanged(const QItemSelection &selected, const QItemSelection &deselected)

This slot is called when the selection is changed. The previous selection (which may be empty), is specified by deselected, and the new selection by selected.

See also setSelection().

### `[virtual protected]` QItemSelectionModel::SelectionFlags QAbstractItemView::selectionCommand(const QModelIndex &index, const QEvent *event = nullptr) const

Returns the SelectionFlags to be used when updating a selection model for the specified index. The result depends on the current selectionMode(), and on the user input event event, which can be `nullptr`.

Reimplement this function to define your own selection behavior.

See also setSelection().

### QItemSelectionModel *QAbstractItemView::selectionModel() const

Returns the current selection model.

See also setSelectionModel() and selectedIndexes().

### `[slot]` void QAbstractItemView::setCurrentIndex(const QModelIndex &index)

Sets the current item to be the item at index.

Unless the current selection mode is NoSelection, the item is also selected. Note that this function also updates the starting position for any new selections the user performs.

To set an item as the current item without selecting it, call

`selectionModel()->setCurrentIndex(index, QItemSelectionModel::NoUpdate);`

See also currentIndex(), currentChanged(), and selectionMode.

### `[protected]` void QAbstractItemView::setDirtyRegion(const QRegion &region)

Marks the given region as dirty and schedules it to be updated. You only need to call this function if you are implementing your own view subclass.

See also scrollDirtyRegion() and dirtyRegionOffset().

### void QAbstractItemView::setIndexWidget(const QModelIndex &index, QWidget *widget)

Sets the given widget on the item at the given index, passing the ownership of the widget to the viewport.

If index is invalid (e.g., if you pass the root index), this function will do nothing.

The given widget's autoFillBackground property must be set to true, otherwise the widget's background will be transparent, showing both the model data and the item at the given index.

Note: The view takes ownership of the widget. This means if index widget A is replaced with index widget B, index widget A will be deleted. For example, in the code snippet below, the QLineEdit object will be deleted.

     setIndexWidget(index, new QLineEdit);
     ...
     setIndexWidget(index, new QTextEdit);

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 QStyledItemDelegate instead.

See also indexWidget() and Delegate Classes.

### void QAbstractItemView::setItemDelegate(QAbstractItemDelegate *delegate)

Sets the item delegate for this view and its model to delegate. This is useful if you want complete control over the editing and display of items.

Any existing delegate will be removed, but not deleted. QAbstractItemView does not take ownership of delegate.

Warning: You should not share the same instance of a delegate between views. Doing so can cause incorrect or unintuitive editing behavior since each view connected to a given delegate may receive the closeEditor() signal, and attempt to access, modify or close an editor that has already been closed.

See also itemDelegate().

### void QAbstractItemView::setItemDelegateForColumn(int column, QAbstractItemDelegate *delegate)

Sets the given item delegate used by this view and model for the given column. All items on column will be drawn and managed by delegate instead of using the default delegate (i.e., itemDelegate()).

Any existing column delegate for column will be removed, but not deleted. QAbstractItemView does not take ownership of delegate.

Note: If a delegate has been assigned to both a row and a column, the row delegate will take precedence and manage the intersecting cell index.

Warning: You should not share the same instance of a delegate between views. Doing so can cause incorrect or unintuitive editing behavior since each view connected to a given delegate may receive the closeEditor() signal, and attempt to access, modify or close an editor that has already been closed.

See also itemDelegateForColumn(), setItemDelegateForRow(), and itemDelegate().

### void QAbstractItemView::setItemDelegateForRow(int row, QAbstractItemDelegate *delegate)

Sets the given item delegate used by this view and model for the given row. All items on row will be drawn and managed by delegate instead of using the default delegate (i.e., itemDelegate()).

Any existing row delegate for row will be removed, but not deleted. QAbstractItemView does not take ownership of delegate.

Note: If a delegate has been assigned to both a row and a column, the row delegate (i.e., this delegate) will take precedence and manage the intersecting cell index.

Warning: You should not share the same instance of a delegate between views. Doing so can cause incorrect or unintuitive editing behavior since each view connected to a given delegate may receive the closeEditor() signal, and attempt to access, modify or close an editor that has already been closed.

See also itemDelegateForRow(), setItemDelegateForColumn(), and itemDelegate().

### `[virtual]` void QAbstractItemView::setModel(QAbstractItemModel *model)

Sets the model for the view to present.

This function will create and set a new selection model, replacing any model that was previously set with setSelectionModel(). However, the old selection model will not be deleted as it may be shared between several views. We recommend that you delete the old selection model if it is no longer required. This is done with the following code:

     QItemSelectionModel *m = view->selectionModel();
     view->setModel(new model);
     delete m;

If both the old model and the old selection model do not have parents, or if their parents are long-lived objects, it may be preferable to call their deleteLater() functions to explicitly delete them.

The view does not take ownership of the model unless it is the model's parent object because the model may be shared between many different views.

See also model(), selectionModel(), and setSelectionModel().

### `[virtual slot]` void QAbstractItemView::setRootIndex(const QModelIndex &index)

Sets the root item to the item at the given index.

See also rootIndex().

### `[pure virtual protected]` void QAbstractItemView::setSelection(const QRect &rect, QItemSelectionModel::SelectionFlags flags)

Applies the selection flags to the items in or touched by the rectangle, rect.

When implementing your own itemview setSelection should call selectionModel()->select(selection, flags) where selection is either an empty QModelIndex or a QItemSelection that contains all items that are contained in rect.

See also selectionCommand() and selectedIndexes().

### `[virtual]` void QAbstractItemView::setSelectionModel(QItemSelectionModel *selectionModel)

Sets the current selection model to the given selectionModel.

Note that, if you call setModel() after this function, the given selectionModel will be replaced by one created by the view.

Note: It is up to the application to delete the old selection model if it is no longer needed; i.e., if it is not being used by other views. This will happen automatically when its parent object is deleted. However, if it does not have a parent, or if the parent is a long-lived object, it may be preferable to call its deleteLater() function to explicitly delete it.

See also selectionModel(), setModel(), and clearSelection().

### `[protected]` void QAbstractItemView::setState(QAbstractItemView::State state)

Sets the item view's state to the given state.

See also state().

### `[virtual]` int QAbstractItemView::sizeHintForColumn(int column) const

Returns the width size hint for the specified column or -1 if there is no model.

This function is used in views with a horizontal header to find the size hint for a header section based on the contents of the given column.

See also sizeHintForRow().

### QSize QAbstractItemView::sizeHintForIndex(const QModelIndex &index) const

Returns the size hint for the item with the specified index or an invalid size for invalid indexes.

See also sizeHintForRow() and sizeHintForColumn().

### `[virtual]` int QAbstractItemView::sizeHintForRow(int row) const

Returns the height size hint for the specified row or -1 if there is no model.

The returned height is calculated using the size hints of the given row's items, i.e. the returned value is the maximum height among the items. Note that to control the height of a row, you must reimplement the QAbstractItemDelegate::sizeHint() function.

This function is used in views with a vertical header to find the size hint for a header section based on the contents of the given row.

See also sizeHintForColumn().

### `[virtual protected]` void QAbstractItemView::startDrag(Qt::DropActions supportedActions)

Starts a drag by calling drag->exec() using the given supportedActions.

### `[protected]` QAbstractItemView::State QAbstractItemView::state() const

Returns the item view's state.

See also setState().

### `[override virtual protected]` void QAbstractItemView::timerEvent(QTimerEvent *event)

Reimplements: QObject::timerEvent(QTimerEvent *event).

This function is called with the given event when a timer event is sent to the widget.

See also QObject::timerEvent().

### `[slot]` void QAbstractItemView::update(const QModelIndex &index)

Updates the area occupied by the given index.

### `[virtual protected slot]` void QAbstractItemView::updateGeometries()

Updates the geometry of the child widgets of the view.

### `[pure virtual protected]` int QAbstractItemView::verticalOffset() const

Returns the vertical offset of the view.

In the base class this is a pure virtual function.

See also horizontalOffset().

### `[signal]` void QAbstractItemView::viewportEntered()

This signal is emitted when the mouse cursor enters the viewport. Mouse tracking needs to be enabled for this feature to work.

See also entered().

### `[override virtual protected]` bool QAbstractItemView::viewportEvent(QEvent *event)

Reimplements: QAbstractScrollArea::viewportEvent(QEvent *event).

This function is used to handle tool tips, and What's This? mode, if the given event is a QEvent::ToolTip,or a QEvent::WhatsThis. It passes all other events on to its base class viewportEvent() handler.

Returns `true` if event has been recognized and processed; otherwise, returns `false`.

### `[override virtual protected]` QSize QAbstractItemView::viewportSizeHint() const

Reimplements: QAbstractScrollArea::viewportSizeHint() const.

### `[pure virtual]` QRect QAbstractItemView::visualRect(const QModelIndex &index) const

Returns the rectangle on the viewport occupied by the item at index.

If your item is displayed in several areas then visualRect should return the primary area that contains index and not the complete area that index might encompasses, touch or cause drawing.

In the base class this is a pure virtual function.

See also indexAt() and visualRegionForSelection().

### `[pure virtual protected]` QRegion QAbstractItemView::visualRegionForSelection(const QItemSelection &selection) const

Returns the region from the viewport of the items in the given selection.

In the base class this is a pure virtual function.

See also visualRect() and selectedIndexes().