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The QAction class provides an abstract user interface action that can be inserted into widgets. More...
Inherits QObject.
Inherited by QWidgetAction.
The QAction class provides an abstract user interface action that can be inserted into widgets.
In applications many common commands can be invoked via menus, toolbar buttons, and keyboard shortcuts. Since the user expects each command to be performed in the same way, regardless of the user interface used, it is useful to represent each command as an action.
Actions can be added to menus and toolbars, and will automatically keep them in sync. For example, in a word processor, if the user presses a Bold toolbar button, the Bold menu item will automatically be checked.
Actions can be created as independent objects, but they may also be created during the construction of menus; the QMenu class contains convenience functions for creating actions suitable for use as menu items.
A QAction may contain an icon, menu text, a shortcut, status text, "What's This?" text, and a tooltip. Most of these can be set in the constructor. They can also be set independently with setIcon(), setText(), setIconText(), setShortcut(), setStatusTip(), setWhatsThis(), and setToolTip(). For menu items, it is possible to set an individual font with setFont().
Actions are added to widgets using QWidget.addAction() or QGraphicsWidget.addAction(). Note that an action must be added to a widget before it can be used; this is also true when the shortcut should be global (i.e., Qt.ApplicationShortcut as Qt.ShortcutContext).
Once a QAction has been created it should be added to the relevant menu and toolbar, then connected to the slot which will perform the action. For example:
openAct = new QAction(QIcon(":/images/open.png"), tr("&Open..."), this);
openAct->setShortcuts(QKeySequence.Open);
openAct->setStatusTip(tr("Open an existing file"));
connect(openAct, SIGNAL(triggered()), this, SLOT(open()));
fileMenu->addAction(openAct);
fileToolBar->addAction(openAct);
We recommend that actions are created as children of the window they are used in. In most cases actions will be children of the application's main window.
This enum type is used when calling QAction.activate()
| Constant | Value | Description |
|---|---|---|
| QAction.Trigger | 0 | this will cause the QAction.triggered() signal to be emitted. |
| QAction.Hover | 1 | this will cause the QAction.hovered() signal to be emitted. |
This enum describes how an action should be moved into the application menu on Mac OS X.
| Constant | Value | Description |
|---|---|---|
| QAction.NoRole | 0 | This action should not be put into the application menu |
| QAction.TextHeuristicRole | 1 | This action should be put in the application menu based on the action's text as described in the QMenuBar documentation. |
| QAction.ApplicationSpecificRole | 2 | This action should be put in the application menu with an application specific role |
| QAction.AboutQtRole | 3 | This action matches handles the "About Qt" menu item. |
| QAction.AboutRole | 4 | This action should be placed where the "About" menu item is in the application menu. The text of the menu item will be set to "About <application name>". The application name is fetched from the Info.plist file in the application's bundle (See Deploying an Application on Mac OS X). |
| QAction.PreferencesRole | 5 | This action should be placed where the "Preferences..." menu item is in the application menu. |
| QAction.QuitRole | 6 | This action should be placed where the Quit menu item is in the application menu. |
Setting this value only has effect on items that are in the immediate menus of the menubar, not the submenus of those menus. For example, if you have File menu in your menubar and the File menu has a submenu, setting the MenuRole for the actions in that submenu have no effect. They will never be moved.
This enum defines priorities for actions in user interface.
| Constant | Value | Description |
|---|---|---|
| QAction.LowPriority | 0 | The action should not be prioritized in the user interface. |
| QAction.NormalPriority | 128 | |
| QAction.HighPriority | 256 | The action should be prioritized in the user interface. |
This enum was introduced or modified in Qt 4.6.
See also priority.
This enum describes how an action should be placed in the softkey bar. Currently this enum only has an effect on the Symbian platform.
| Constant | Value | Description |
|---|---|---|
| QAction.NoSoftKey | 0 | This action should not be used as a softkey |
| QAction.PositiveSoftKey | 1 | This action is used to describe a softkey with a positive or non-destructive role such as Ok, Select, or Options. |
| QAction.NegativeSoftKey | 2 | This action is used to describe a soft ey with a negative or destructive role role such as Cancel, Discard, or Close. |
| QAction.SelectSoftKey | 3 | This action is used to describe a role that selects a particular item or widget in the application. |
Actions with a softkey role defined are only visible in the softkey bar when the widget containing the action has focus. If no widget currently has focus, the softkey framework will traverse up the widget parent hierarchy looking for a widget containing softkey actions.
This enum was introduced or modified in Qt 4.6.
The parent argument, if not None, causes self to be owned by Qt instead of PyQt.
Constructs an action with parent. If parent is an action group the action will be automatically inserted into the group.
The parent argument, if not None, causes self to be owned by Qt instead of PyQt.
Constructs an action with some text and parent. If parent is an action group the action will be automatically inserted into the group.
The action uses a stripped version of text (e.g. "&Menu Option..." becomes "Menu Option") as descriptive text for tool buttons. You can override this by setting a specific description with setText(). The same text will be used for tooltips unless you specify a different text using setToolTip().
The parent argument, if not None, causes self to be owned by Qt instead of PyQt.
Constructs an action with an icon and some text and parent. If parent is an action group the action will be automatically inserted into the group.
The action uses a stripped version of text (e.g. "&Menu Option..." becomes "Menu Option") as descriptive text for tool buttons. You can override this by setting a specific description with setText(). The same text will be used for tooltips unless you specify a different text using setToolTip().
Returns the action group for this action. If no action group manages this action then 0 will be returned.
See also QActionGroup and QAction.setActionGroup().
Sends the relevant signals for ActionEvent event.
Action based widgets use this API to cause the QAction to emit signals as well as emitting their own.
Returns a list of widgets this action has been added to.
This function was introduced in Qt 4.5.
See also QWidget.addAction() and associatedWidgets().
Returns a list of widgets this action has been added to.
This function was introduced in Qt 4.2.
See also QWidget.addAction() and associatedGraphicsWidgets().
Returns the user data as set in QAction.setData.
See also setData().
Reimplemented from QObject.event().
This method is also a Qt slot with the C++ signature void hover().
This is a convenience slot that calls activate(Hover).
Returns true if this action is a separator action; otherwise it returns false.
See also QAction.setSeparator().
Returns the menu contained by this action. Actions that contain menus can be used to create menu items with submenus, or inserted into toolbars to create buttons with popup menus.
See also setMenu() and QMenu.addAction().
Returns the parent widget.
Sets this action group to group. The action will be automatically added to the group's list of actions.
Actions within the group will be mutually exclusive.
See also QActionGroup and QAction.actionGroup().
This method is also a Qt slot with the C++ signature void setChecked(bool).
Sets the action's internal data to the given userData.
See also data().
This method is also a Qt slot with the C++ signature void setDisabled(bool).
This is a convenience function for the enabled property, that is useful for signals--slots connections. If b is true the action is disabled; otherwise it is enabled.
This method is also a Qt slot with the C++ signature void setEnabled(bool).
Sets the menu contained by this action to the specified menu.
See also menu().
If b is true then this action will be considered a separator.
How a separator is represented depends on the widget it is inserted into. Under most circumstances the text, submenu, and icon will be ignored for separator actions.
See also QAction.isSeparator().
Sets shortcuts as the list of shortcuts that trigger the action. The first element of the list is the primary shortcut.
This function was introduced in Qt 4.2.
See also shortcuts() and shortcut.
Sets a platform dependent list of shortcuts based on the key. The result of calling this function will depend on the currently running platform. Note that more than one shortcut can assigned by this action. If only the primary shortcut is required, use setShortcut instead.
This function was introduced in Qt 4.2.
See also QKeySequence.keyBindings().
This method is also a Qt slot with the C++ signature void setVisible(bool).
Returns the list of shortcuts, with the primary shortcut as the first element of the list.
This function was introduced in Qt 4.2.
See also setShortcuts().
Updates the relevant status bar for the widget specified by sending a QStatusTipEvent to its parent widget. Returns true if an event was sent; otherwise returns false.
If a null widget is specified, the event is sent to the action's parent.
See also statusTip.
This method is also a Qt slot with the C++ signature void toggle().
This is a convenience function for the checked property. Connect to it to change the checked state to its opposite state.
This method is also a Qt slot with the C++ signature void trigger().
This is a convenience slot that calls activate(Trigger).
This is the default overload of this signal.
This signal is emitted when an action has changed. If you are only interested in actions in a given widget, you can watch for QWidget.actionEvent() sent with an QEvent.ActionChanged.
See also QWidget.actionEvent().
This is the default overload of this signal.
This signal is emitted when an action is highlighted by the user; for example, when the user pauses with the cursor over a menu option, toolbar button, or presses an action's shortcut key combination.
See also QAction.activate().
This is the default overload of this signal.
This signal is emitted whenever a checkable action changes its isChecked() status. This can be the result of a user interaction, or because setChecked() was called.
checked is true if the action is checked, or false if the action is unchecked.
See also QAction.activate(), QAction.triggered(), and checked.
This is the default overload of this signal.
This signal is emitted when an action is activated by the user; for example, when the user clicks a menu option, toolbar button, or presses an action's shortcut key combination, or when trigger() was called. Notably, it is not emitted when setChecked() or toggle() is called.
If the action is checkable, checked is true if the action is checked, or false if the action is unchecked.
See also QAction.activate(), QAction.toggled(), and checked.
| PyQt 4.9.4 for Windows | Copyright © Riverbank Computing Ltd and Nokia 2012 | Qt 4.8.2 |