QDockWidget Class

Member Function Documentation

[explicit] QDockWidget::QDockWidget(QWidget *parent = nullptr, Qt::WindowFlags flags = Qt::WindowFlags())

Constructs a QDockWidget with parent parent and window flags flags. The dock widget will be placed in the left dock widget area.

[explicit] QDockWidget::QDockWidget(const QString &title, QWidget *parent = nullptr, Qt::WindowFlags flags = Qt::WindowFlags())

Constructs a QDockWidget with parent parent and window flags flags. The dock widget will be placed in the left dock widget area.

The window title is set to title. This title is used when the QDockWidget is docked and undocked. It is also used in the context menu provided by QMainWindow.

See also setWindowTitle().

[virtual noexcept] QDockWidget::~QDockWidget()

Destroys the dock widget.

[signal] void QDockWidget::allowedAreasChanged(Qt::DockWidgetAreas allowedAreas)

This signal is emitted when the allowedAreas property changes. The allowedAreas parameter gives the new value of the property.

[override virtual protected] void QDockWidget::changeEvent(QEvent *event)

Reimplements: QWidget::changeEvent(QEvent *event).

[override virtual protected] void QDockWidget::closeEvent(QCloseEvent *event)

Reimplements: QWidget::closeEvent(QCloseEvent *event).

[signal] void QDockWidget::dockLocationChanged(Qt::DockWidgetArea area)

This signal is emitted when the dock widget is moved to another dock area, or is moved to a different location in its current dock area. This happens when the dock widget is moved programmatically or is dragged to a new location by the user.

[override virtual protected] bool QDockWidget::event(QEvent *event)

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

[signal] void QDockWidget::featuresChanged(QDockWidget::DockWidgetFeatures features)

This signal is emitted when the features property changes. The features parameter gives the new value of the property.

[virtual protected] void QDockWidget::initStyleOption(QStyleOptionDockWidget *option) const

Initialize option with the values from this QDockWidget. This method is useful for subclasses when they need a QStyleOptionDockWidget, but don't want to fill in all the information themselves.

See also QStyleOption::initFrom().

bool QDockWidget::isAreaAllowed(Qt::DockWidgetArea area) const

Returns true if this dock widget can be placed in the given area; otherwise returns false.

[override virtual protected] void QDockWidget::paintEvent(QPaintEvent *event)

Reimplements: QWidget::paintEvent(QPaintEvent *event).

void QDockWidget::setTitleBarWidget(QWidget *widget)

Sets an arbitrary widget as the dock widget's title bar. If widget is nullptr, any custom title bar widget previously set on the dock widget is removed, but not deleted, and the default title bar will be used instead.

If a title bar widget is set, QDockWidget will not use native window decorations when it is floated.

Here are some tips for implementing custom title bars:

• Mouse events that are not explicitly handled by the title bar widget must be ignored by calling QMouseEvent::ignore(). These events then propagate to the QDockWidget parent, which handles them in the usual manner, moving when the title bar is dragged, docking and undocking when it is double-clicked, etc.
• When DockWidgetVerticalTitleBar is set on QDockWidget, the title bar widget is repositioned accordingly. In resizeEvent(), the title bar should check what orientation it should assume:

  QDockWidget *dockWidget = qobject_cast<QDockWidget*>(parentWidget());
  if (dockWidget->features() & QDockWidget::DockWidgetVerticalTitleBar) {
      // I need to be vertical
  } else {
      // I need to be horizontal
  }

• The title bar widget must have a valid QWidget::sizeHint() and QWidget::minimumSizeHint(). These functions should take into account the current orientation of the title bar.
• It is not possible to remove a title bar from a dock widget. However, a similar effect can be achieved by setting a default constructed QWidget as the title bar widget.

Using qobject_cast() as shown above, the title bar widget has full access to its parent QDockWidget. Hence it can perform such operations as docking and hiding in response to user actions.

See also titleBarWidget() and DockWidgetVerticalTitleBar.

void QDockWidget::setWidget(QWidget *widget)

Sets the widget for the dock widget to widget.

If the dock widget is visible when widget is added, you must show() it explicitly.

Note that you must add the layout of the widget before you call this function; if not, the widget will not be visible.

See also widget().

QWidget *QDockWidget::titleBarWidget() const

Returns the custom title bar widget set on the QDockWidget, or nullptr if no custom title bar has been set.

See also setTitleBarWidget().

QAction *QDockWidget::toggleViewAction() const

Returns a checkable action that can be added to menus and toolbars so that the user can show or close this dock widget.

The action's text is set to the dock widget's window title.

See also QAction::text and QWidget::windowTitle.

[signal] void QDockWidget::topLevelChanged(bool topLevel)

This signal is emitted when the floating property changes. The topLevel parameter is true if the dock widget is now floating; otherwise it is false.

See also isWindow().

[signal] void QDockWidget::visibilityChanged(bool visible)

This signal is emitted when the dock widget becomes visible (or invisible). This happens when the widget is hidden or shown, as well as when it is docked in a tabbed dock area and its tab becomes selected or unselected.

QWidget *QDockWidget::widget() const

Returns the widget for the dock widget. This function returns zero if the widget has not been set.

See also setWidget().