QDockWidget 类

QDockWidget 类提供可以停放的小部件在 QMainWindow 或浮动在桌面上作为顶层窗口。 更多...

Header: #include <QDockWidget>
CMake: find_package(Qt6 COMPONENTS Widgets REQUIRED)
target_link_libraries(mytarget PRIVATE Qt6::Widgets)
qmake: QT += widgets
继承: QWidget


enum DockWidgetFeature { DockWidgetClosable, DockWidgetMovable, DockWidgetFloatable, DockWidgetVerticalTitleBar, NoDockWidgetFeatures }
flags DockWidgetFeatures



QDockWidget (QWidget * parent = nullptr, Qt::WindowFlags flags = Qt::WindowFlags())
QDockWidget (const QString & title , QWidget * parent = nullptr, Qt::WindowFlags flags = Qt::WindowFlags())
virtual ~QDockWidget ()
Qt::DockWidgetAreas allowedAreas () const
QDockWidget::DockWidgetFeatures features () const
bool isAreaAllowed (Qt::DockWidgetArea area ) const
bool isFloating () const
void setAllowedAreas (Qt::DockWidgetAreas areas )
void setFeatures (QDockWidget::DockWidgetFeatures features )
void setFloating (bool floating )
void setTitleBarWidget (QWidget * widget )
void setWidget (QWidget * widget )
QWidget * titleBarWidget () const
QAction * toggleViewAction () const
QWidget * widget () const


void allowedAreasChanged (Qt::DockWidgetAreas allowedAreas )
void dockLocationChanged (Qt::DockWidgetArea area )
void featuresChanged (QDockWidget::DockWidgetFeatures features )
void topLevelChanged (bool topLevel )
void visibilityChanged (bool visible )


virtual void initStyleOption (QStyleOptionDockWidget * option ) const


virtual void changeEvent (QEvent * event ) override
virtual void closeEvent (QCloseEvent * event ) override
virtual bool event (QEvent * event ) override
virtual void paintEvent (QPaintEvent * event ) override


QDockWidget provides the concept of dock widgets, also know as tool palettes or utility windows. Dock windows are secondary windows placed in the dock widget area around the central widget QMainWindow .

Dock windows can be moved inside their current area, moved into new areas and floated (e.g., undocked) by the end-user. The QDockWidget API allows the programmer to restrict the dock widgets ability to move, float and close, as well as the areas in which they can be placed.


A QDockWidget consists of a title bar and the content area. The title bar displays the dock widgets 窗口标题 float button and a close button. Depending on the state of the QDockWidget, the float and close buttons may be either disabled or not shown at all.

The visual appearance of the title bar and buttons is dependent on the style in use.

A QDockWidget acts as a wrapper for its child widget, set with setWidget (). Custom size hints, minimum and maximum sizes and size policies should be implemented in the child widget. QDockWidget will respect them, adjusting its own constraints to include the frame and title. Size constraints should not be set on the QDockWidget itself, because they change depending on whether it is docked; a docked QDockWidget has no frame and a smaller title bar.

另请参阅 QMainWindow and 停放 Widget 范例 .


enum QDockWidget:: DockWidgetFeature
flags QDockWidget:: DockWidgetFeatures

常量 描述
QDockWidget::DockWidgetClosable 0x01 The dock widget can be closed. On some systems the dock widget always has a close button when it's floating (for example on MacOS 10.5).
QDockWidget::DockWidgetMovable 0x02 The dock widget can be moved between docks by the user.
QDockWidget::DockWidgetFloatable 0x04 The dock widget can be detached from the main window, and floated as an independent window.
QDockWidget::DockWidgetVerticalTitleBar 0x08 The dock widget displays a vertical title bar on its left side. This can be used to increase the amount of vertical space in a QMainWindow .
QDockWidget::NoDockWidgetFeatures 0x00 The dock widget cannot be closed, moved, or floated.

DockWidgetFeatures 类型是 typedef 对于 QFlags <DockWidgetFeature>. It stores an OR combination of DockWidgetFeature values.


allowedAreas : Qt::DockWidgetAreas

areas where the dock widget may be placed

默认为 Qt::AllDockWidgetAreas .


Qt::DockWidgetAreas allowedAreas () const
void setAllowedAreas (Qt::DockWidgetAreas areas )


void allowedAreasChanged (Qt::DockWidgetAreas allowedAreas )

另请参阅 Qt::DockWidgetArea .

features : DockWidgetFeatures

This property holds whether the dock widget is movable, closable, and floatable

By default, this property is set to a combination of DockWidgetClosable , DockWidgetMovable and DockWidgetFloatable .


QDockWidget::DockWidgetFeatures features () const
void setFeatures (QDockWidget::DockWidgetFeatures features )


void featuresChanged (QDockWidget::DockWidgetFeatures features )

另请参阅 DockWidgetFeature .

floating : bool

此特性保持停放 Widget 是否浮动

A floating dock widget is presented to the user as an independent window "on top" of its parent QMainWindow , instead of being docked in the QMainWindow .

默认情况下此特性为 true .

当此特性改变时, topLevelChanged() 信号被发射。


bool isFloating () const
void setFloating (bool floating )

另请参阅 isWindow () 和 topLevelChanged ().

windowTitle : QString

此特性保持停放 Widget 标题 (题注)



QString windowTitle () const
void setWindowTitle (const QString &)


void windowTitleChanged (const QString & title )


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

构造 QDockWidget 采用父级 parent 和窗口标志 flags . The dock widget will be placed in the left dock widget area.

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

构造 QDockWidget 采用父级 parent 和窗口标志 flags . The dock widget will be placed in the left dock widget area.

窗口标题被设为 title . This title is used when the QDockWidget is docked and undocked. It is also used in the context menu provided by QMainWindow .

另请参阅 setWindowTitle ().

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

此信号被发射当 allowedAreas 特性改变。 allowedAreas parameter gives the new value of the property.

注意: 通知程序信号为特性 allowedAreas .

[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.

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

此信号被发射当 features 特性改变。 features parameter gives the new value of the property.

注意: 通知程序信号为特性 features .

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

此信号被发射当 floating 特性改变。 topLevel parameter is true if the dock widget is now floating; otherwise it is false.

另请参阅 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.

[virtual] QDockWidget:: ~QDockWidget ()

Destroys the dock widget.

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

重实现: QWidget::changeEvent (QEvent *event).

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

重实现: QWidget::closeEvent (QCloseEvent *event).

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

重实现: QWidget::event (QEvent *event).

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

初始化 option 采用值来自此 QDockWidget 。此方法对子类是有用的,当需要 QStyleOptionDockWidget ,但不希望自己填充所有信息。

另请参阅 QStyleOption::initFrom ().

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

返回 true if this dock widget can be placed in the given area ;否则返回 false .

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

重实现: 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.
  • 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 () 和 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.

使用 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.

另请参阅 titleBarWidget () 和 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.

另请参阅 widget ().

QWidget *QDockWidget:: titleBarWidget () const

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

另请参阅 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.

注意: The action can not be used to programmatically show or hide the dock widget. Use the visible property for that.

另请参阅 QAction::text and QWidget::windowTitle .

QWidget *QDockWidget:: widget () const

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

另请参阅 setWidget ().