QApplication

Inheritance diagram of QApplication

Synopsis

Functions

Virtual functions

Slots

Signals

Static functions

Detailed Description

The PySide.QtGui.QApplication class manages the GUI application’s control flow and main settings.

PySide.QtGui.QApplication contains the main event loop, where all events from the window system and other sources are processed and dispatched. It also handles the application’s initialization, finalization, and provides session management. In addition, PySide.QtGui.QApplication handles most of the system-wide and application-wide settings.

For any GUI application using Qt, there is precisely onePySide.QtGui.QApplication object, no matter whether the application has 0, 1, 2 or more windows at any given time. For non-GUI Qt applications, use PySide.QtCore.QCoreApplication instead, as it does not depend on the QtGui library.

The PySide.QtGui.QApplication object is accessible through the PySide.QtCore.QCoreApplication.instance() function that returns a pointer equivalent to the global qApp() pointer.

PySide.QtGui.QApplication ‘s main areas of responsibility are:

Since the PySide.QtGui.QApplication object does so much initialization, it must be created before any other objects related to the user interface are created. PySide.QtGui.QApplication also deals with common command line arguments. Hence, it is usually a good idea to create it before any interpretation or modification of argv is done in the application itself.

Groups of functions
System settings PySide.QtGui.QApplication.desktopSettingsAware() , PySide.QtGui.QApplication.setDesktopSettingsAware() , PySide.QtGui.QApplication.cursorFlashTime() , PySide.QtGui.QApplication.setCursorFlashTime() , PySide.QtGui.QApplication.doubleClickInterval() , PySide.QtGui.QApplication.setDoubleClickInterval() , PySide.QtGui.QApplication.setKeyboardInputInterval() , PySide.QtGui.QApplication.wheelScrollLines() , PySide.QtGui.QApplication.setWheelScrollLines() , PySide.QtGui.QApplication.palette() , PySide.QtGui.QApplication.setPalette() , PySide.QtGui.QApplication.font() , PySide.QtGui.QApplication.setFont() , PySide.QtGui.QApplication.fontMetrics() . PySide.QtGui.QApplication.desktopSettingsAware() , PySide.QtGui.QApplication.setDesktopSettingsAware() , PySide.QtGui.QApplication.cursorFlashTime() , PySide.QtGui.QApplication.setCursorFlashTime() , PySide.QtGui.QApplication.doubleClickInterval() , PySide.QtGui.QApplication.setDoubleClickInterval() , PySide.QtGui.QApplication.setKeyboardInputInterval() , PySide.QtGui.QApplication.wheelScrollLines() , PySide.QtGui.QApplication.setWheelScrollLines() , PySide.QtGui.QApplication.palette() , PySide.QtGui.QApplication.setPalette() , PySide.QtGui.QApplication.font() , PySide.QtGui.QApplication.setFont() , PySide.QtGui.QApplication.fontMetrics() .
Event handling exec() , PySide.QtCore.QCoreApplication.processEvents() , PySide.QtCore.QCoreApplication.exit() , PySide.QtCore.QCoreApplication.quit() . PySide.QtCore.QCoreApplication.sendEvent() , PySide.QtCore.QCoreApplication.postEvent() , PySide.QtCore.QCoreApplication.sendPostedEvents() , PySide.QtCore.QCoreApplication.removePostedEvents() , PySide.QtCore.QCoreApplication.hasPendingEvents() , PySide.QtGui.QApplication.notify() , macEventFilter() , qwsEventFilter() , x11EventFilter() , x11ProcessEvent() , winEventFilter() . exec() , PySide.QtCore.QCoreApplication.processEvents() , PySide.QtCore.QCoreApplication.exit() , PySide.QtCore.QCoreApplication.quit() . PySide.QtCore.QCoreApplication.sendEvent() , PySide.QtCore.QCoreApplication.postEvent() , PySide.QtCore.QCoreApplication.sendPostedEvents() , PySide.QtCore.QCoreApplication.removePostedEvents() , PySide.QtCore.QCoreApplication.hasPendingEvents() , PySide.QtGui.QApplication.notify() , macEventFilter() , qwsEventFilter() , x11EventFilter() , x11ProcessEvent() , winEventFilter() .
GUI Styles PySide.QtGui.QApplication.style() , PySide.QtGui.QApplication.setStyle() . PySide.QtGui.QApplication.style() , PySide.QtGui.QApplication.setStyle() .
Color usage PySide.QtGui.QApplication.colorSpec() , PySide.QtGui.QApplication.setColorSpec() , qwsSetCustomColors() . PySide.QtGui.QApplication.colorSpec() , PySide.QtGui.QApplication.setColorSpec() , qwsSetCustomColors() .
Text handling PySide.QtCore.QCoreApplication.installTranslator() , PySide.QtCore.QCoreApplication.removeTranslator() PySide.QtCore.QCoreApplication.translate() . PySide.QtCore.QCoreApplication.installTranslator() , PySide.QtCore.QCoreApplication.removeTranslator() PySide.QtCore.QCoreApplication.translate() .
Widgets PySide.QtGui.QApplication.allWidgets() , PySide.QtGui.QApplication.topLevelWidgets() , PySide.QtGui.QApplication.desktop() , PySide.QtGui.QApplication.activePopupWidget() , PySide.QtGui.QApplication.activeModalWidget() , PySide.QtGui.QApplication.clipboard() , PySide.QtGui.QApplication.focusWidget() , PySide.QtGui.QApplication.activeWindow() , PySide.QtGui.QApplication.widgetAt() . PySide.QtGui.QApplication.allWidgets() , PySide.QtGui.QApplication.topLevelWidgets() , PySide.QtGui.QApplication.desktop() , PySide.QtGui.QApplication.activePopupWidget() , PySide.QtGui.QApplication.activeModalWidget() , PySide.QtGui.QApplication.clipboard() , PySide.QtGui.QApplication.focusWidget() , PySide.QtGui.QApplication.activeWindow() , PySide.QtGui.QApplication.widgetAt() .
Advanced cursor handling PySide.QtGui.QApplication.overrideCursor() , PySide.QtGui.QApplication.setOverrideCursor() , PySide.QtGui.QApplication.restoreOverrideCursor() . PySide.QtGui.QApplication.overrideCursor() , PySide.QtGui.QApplication.setOverrideCursor() , PySide.QtGui.QApplication.restoreOverrideCursor() .
X Window System synchronization flushX() , PySide.QtGui.QApplication.syncX() . flushX() , PySide.QtGui.QApplication.syncX() .
Session management PySide.QtGui.QApplication.isSessionRestored() , PySide.QtGui.QApplication.sessionId() , PySide.QtGui.QApplication.commitData() , PySide.QtGui.QApplication.saveState() . PySide.QtGui.QApplication.isSessionRestored() , PySide.QtGui.QApplication.sessionId() , PySide.QtGui.QApplication.commitData() , PySide.QtGui.QApplication.saveState() .
Miscellaneous PySide.QtGui.QApplication.closeAllWindows() , PySide.QtCore.QCoreApplication.startingUp() , PySide.QtCore.QCoreApplication.closingDown() , PySide.QtGui.QApplication.type() . PySide.QtGui.QApplication.closeAllWindows() , PySide.QtCore.QCoreApplication.startingUp() , PySide.QtCore.QCoreApplication.closingDown() , PySide.QtGui.QApplication.type() .
class PySide.QtGui.QApplication(arg__1)
class PySide.QtGui.QApplication(arg__1, arg__2)
class PySide.QtGui.QApplication(arg__1, arg__2)
Parameters:
PySide.QtGui.QApplication.Type
Constant Description
QApplication.Tty a console application
QApplication.GuiClient a GUI client application
QApplication.GuiServer a GUI server application (for Qt for Embedded Linux)
PySide.QtGui.QApplication.ColorSpec
Constant Description
QApplication.NormalColor the default color allocation policy
QApplication.CustomColor the same as NormalColor for X11; allocates colors to a palette on demand under Windows
QApplication.ManyColor the right choice for applications that use thousands of colors

See PySide.QtGui.QApplication.setColorSpec() for full details.

static PySide.QtGui.QApplication.aboutQt()

Displays a simple message box about Qt. The message includes the version number of Qt being used by the application.

This is useful for inclusion in the Help menu of an application, as shown in the Menus example.

This function is a convenience slot for QMessageBox.aboutQt() .

static PySide.QtGui.QApplication.activeModalWidget()
Return type:PySide.QtGui.QWidget

Returns the active modal widget.

A modal widget is a special top-level widget which is a subclass of PySide.QtGui.QDialog that specifies the modal parameter of the constructor as true. A modal widget must be closed before the user can continue with other parts of the program.

Modal widgets are organized in a stack. This function returns the active modal widget at the top of the stack.

static PySide.QtGui.QApplication.activePopupWidget()
Return type:PySide.QtGui.QWidget

Returns the active popup widget.

A popup widget is a special top-level widget that sets the Qt::WType_Popup widget flag, e.g. the PySide.QtGui.QMenu widget. When the application opens a popup widget, all events are sent to the popup. Normal widgets and modal widgets cannot be accessed before the popup widget is closed.

Only other popup widgets may be opened when a popup widget is shown. The popup widgets are organized in a stack. This function returns the active popup widget at the top of the stack.

static PySide.QtGui.QApplication.activeWindow()
Return type:PySide.QtGui.QWidget

Returns the application top-level window that has the keyboard input focus, or 0 if no application window has the focus. There might be an PySide.QtGui.QApplication.activeWindow() even if there is no PySide.QtGui.QApplication.focusWidget() , for example if no widget in that window accepts key events.

static PySide.QtGui.QApplication.alert(widget[, duration=0])
Parameters:

Causes an alert to be shown for widget if the window is not the active window. The alert is shown for msec miliseconds. If msec is zero (the default), then the alert is shown indefinitely until the window becomes active again.

Currently this function does nothing on Qt for Embedded Linux.

On Mac OS X, this works more at the application level and will cause the application icon to bounce in the dock.

On Windows, this causes the window’s taskbar entry to flash for a time. If msec is zero, the flashing will stop and the taskbar entry will turn a different color (currently orange).

On X11, this will cause the window to be marked as “demands attention”, the window must not be hidden (i.e. not have hide() called on it, but be visible in some sort of way) in order for this to work.

static PySide.QtGui.QApplication.allWidgets()
Return type:

Returns a list of all the widgets in the application.

The list is empty ( QList.isEmpty() ) if there are no widgets.

Note

Some of the widgets may be hidden.

Example:

def updateAllWidgets():
    for widget in QApplication.allWidgets()
        widget.update()
PySide.QtGui.QApplication.autoSipEnabled()
Return type:PySide.QtCore.bool

This property holds toggles automatic SIP (software input panel) visibility.

Set this property to true to automatically display the SIP when entering widgets that accept keyboard input. This property only affects widgets with the WA_InputMethodEnabled attribute set, and is typically used to launch a virtual keyboard on devices which have very few or no keys.

The property only has an effect on platforms which use software input panels, such as Windows CE and Symbian.

The default is platform dependent.

static PySide.QtGui.QApplication.beep()

Sounds the bell, using the default volume and sound. The function is not available in Qt for Embedded Linux.

static PySide.QtGui.QApplication.changeOverrideCursor(arg__1)
Parameters:arg__1PySide.QtGui.QCursor

Changes the currently active application override cursor to cursor .

This function has no effect if PySide.QtGui.QApplication.setOverrideCursor() was not called.

static PySide.QtGui.QApplication.clipboard()
Return type:PySide.QtGui.QClipboard

Returns a pointer to the application global clipboard.

Note

The PySide.QtGui.QApplication object should already be constructed before accessing the clipboard.

static PySide.QtGui.QApplication.closeAllWindows()

Closes all top-level windows.

This function is particularly useful for applications with many top-level windows. It could, for example, be connected to a Exit entry in the File menu:

exitAct = QAction(tr("E&xit"), self)
exitAct.setShortcut(tr("Ctrl+Q")")
exitAct.setStatusTip(tr("Exit the application")")
connect(exitAct, SIGNAL("triggered()"), qApp, SLOT("closeAllWindows()"))

The windows are closed in random order, until one window does not accept the close event. The application quits when the last window was successfully closed; this can be turned off by setting PySide.QtGui.QApplication.quitOnLastWindowClosed() to false.

static PySide.QtGui.QApplication.colorSpec()
Return type:PySide.QtCore.int

Returns the color specification.

PySide.QtGui.QApplication.commitData(sm)
Parameters:smPySide.QtGui.QSessionManager

This function deals with session management . It is invoked when the PySide.QtGui.QSessionManager wants the application to commit all its data.

Usually this means saving all open files, after getting permission from the user. Furthermore you may want to provide a means by which the user can cancel the shutdown.

You should not exit the application within this function. Instead, the session manager may or may not do this afterwards, depending on the context.

Warning

Within this function, no user interaction is possible, unless you ask the manager for explicit permission. See QSessionManager.allowsInteraction() and QSessionManager.allowsErrorInteraction() for details and example usage.

The default implementation requests interaction and sends a close event to all visible top-level widgets. If any event was rejected, the shutdown is canceled.

PySide.QtGui.QApplication.commitDataRequest(sessionManager)
Parameters:sessionManagerPySide.QtGui.QSessionManager
static PySide.QtGui.QApplication.cursorFlashTime()
Return type:PySide.QtCore.int

This property holds the text cursor’s flash (blink) time in milliseconds.

The flash time is the time required to display, invert and restore the caret display. Usually the text cursor is displayed for half the cursor flash time, then hidden for the same amount of time, but this may vary.

The default value on X11 is 1000 milliseconds. On Windows, the Control Panel value is used and setting this property sets the cursor flash time for all applications.

We recommend that widgets do not cache this value as it may change at any time if the user changes the global desktop settings.

static PySide.QtGui.QApplication.desktop()
Return type:PySide.QtGui.QDesktopWidget

Returns the desktop widget (also called the root window).

The desktop may be composed of multiple screens, so it would be incorrect, for example, to attempt to center some widget in the desktop’s geometry. PySide.QtGui.QDesktopWidget has various functions for obtaining useful geometries upon the desktop, such as QDesktopWidget.screenGeometry() and QDesktopWidget.availableGeometry() .

On X11, it is also possible to draw on the desktop.

static PySide.QtGui.QApplication.desktopSettingsAware()
Return type:PySide.QtCore.bool

Returns true if Qt is set to use the system’s standard colors, fonts, etc.; otherwise returns false. The default is true.

static PySide.QtGui.QApplication.doubleClickInterval()
Return type:PySide.QtCore.int

This property holds the time limit in milliseconds that distinguishes a double click from two consecutive mouse clicks.

The default value on X11 is 400 milliseconds. On Windows and Mac OS, the operating system’s value is used. However, on Windows and Symbian OS, calling this function sets the double click interval for all applications.

PySide.QtGui.QApplication.focusChanged(old, now)
Parameters:
static PySide.QtGui.QApplication.focusWidget()
Return type:PySide.QtGui.QWidget

Returns the application widget that has the keyboard input focus, or 0 if no widget in this application has the focus.

static PySide.QtGui.QApplication.font(arg__1)
Parameters:arg__1PySide.QtGui.QWidget
Return type:PySide.QtGui.QFont

This is an overloaded function.

Returns the default font for the widget .

static PySide.QtGui.QApplication.font()
Return type:PySide.QtGui.QFont

Returns the default application font.

static PySide.QtGui.QApplication.font(className)
Parameters:className – str
Return type:PySide.QtGui.QFont

This is an overloaded function.

Returns the font for widgets of the given className .

PySide.QtGui.QApplication.fontDatabaseChanged()
static PySide.QtGui.QApplication.fontMetrics()
Return type:PySide.QtGui.QFontMetrics

Returns display (screen) font metrics for the application font.

static PySide.QtGui.QApplication.globalStrut()
Return type:PySide.QtCore.QSize

This property holds the minimum size that any GUI element that the user can interact with should have.

For example, no button should be resized to be smaller than the global strut size. The strut size should be considered when reimplementing GUI controls that may be used on touch-screens or similar I/O devices.

Example:

class MyWidget (QWidget):
    # ...
    def sizeHint(self):
        return QSize(80, 25).expandedTo(QApplication.globalStrut())

By default, this property contains a PySide.QtCore.QSize object with zero width and height.

PySide.QtGui.QApplication.inputContext()
Return type:PySide.QtGui.QInputContext

Returns the PySide.QtGui.QInputContext instance used by the application.

static PySide.QtGui.QApplication.isEffectEnabled(arg__1)
Parameters:arg__1PySide.QtCore.Qt.UIEffect
Return type:PySide.QtCore.bool
static PySide.QtGui.QApplication.isLeftToRight()
Return type:PySide.QtCore.bool

Returns true if the application’s layout direction is Qt.LeftToRight ; otherwise returns false.

static PySide.QtGui.QApplication.isRightToLeft()
Return type:PySide.QtCore.bool

Returns true if the application’s layout direction is Qt.RightToLeft ; otherwise returns false.

PySide.QtGui.QApplication.isSessionRestored()
Return type:PySide.QtCore.bool

Returns true if the application has been restored from an earlier session ; otherwise returns false.

static PySide.QtGui.QApplication.keyboardInputDirection()
Return type:PySide.QtCore.Qt.LayoutDirection

Returns the current keyboard input direction.

static PySide.QtGui.QApplication.keyboardInputInterval()
Return type:PySide.QtCore.int

This property holds the time limit in milliseconds that distinguishes a key press from two consecutive key presses.

The default value on X11 is 400 milliseconds. On Windows and Mac OS, the operating system’s value is used.

static PySide.QtGui.QApplication.keyboardInputLocale()
Return type:PySide.QtCore.QLocale

Returns the current keyboard input locale.

static PySide.QtGui.QApplication.keyboardModifiers()
Return type:PySide.QtCore.Qt.KeyboardModifiers

Returns the current state of the modifier keys on the keyboard. The current state is updated sychronously as the event queue is emptied of events that will spontaneously change the keyboard state ( QEvent.KeyPress and QEvent.KeyRelease events).

It should be noted this may not reflect the actual keys held on the input device at the time of calling but rather the modifiers as last reported in one of the above events. If no keys are being held Qt.NoModifier is returned.

PySide.QtGui.QApplication.lastWindowClosed()
static PySide.QtGui.QApplication.layoutDirection()
Return type:PySide.QtCore.Qt.LayoutDirection

This property holds the default layout direction for this application.

On system start-up, the default layout direction depends on the application’s language.

static PySide.QtGui.QApplication.mouseButtons()
Return type:PySide.QtCore.Qt.MouseButtons

Returns the current state of the buttons on the mouse. The current state is updated syncronously as the event queue is emptied of events that will spontaneously change the mouse state ( QEvent.MouseButtonPress and QEvent.MouseButtonRelease events).

It should be noted this may not reflect the actual buttons held on the input device at the time of calling but rather the mouse buttons as last reported in one of the above events. If no mouse buttons are being held Qt.NoButton is returned.

static PySide.QtGui.QApplication.overrideCursor()
Return type:PySide.QtGui.QCursor

Returns the active application override cursor.

This function returns 0 if no application cursor has been defined (i.e. the internal cursor stack is empty).

static PySide.QtGui.QApplication.palette(arg__1)
Parameters:arg__1PySide.QtGui.QWidget
Return type:PySide.QtGui.QPalette

This is an overloaded function.

If a widget is passed, the default palette for the widget’s class is returned. This may or may not be the application palette. In most cases there is no special palette for certain types of widgets, but one notable exception is the popup menu under Windows, if the user has defined a special background color for menus in the display settings.

static PySide.QtGui.QApplication.palette(className)
Parameters:className – str
Return type:PySide.QtGui.QPalette

This is an overloaded function.

Returns the palette for widgets of the given className .

static PySide.QtGui.QApplication.palette()
Return type:PySide.QtGui.QPalette

Returns the application palette.

static PySide.QtGui.QApplication.quitOnLastWindowClosed()
Return type:PySide.QtCore.bool

This property holds whether the application implicitly quits when the last window is closed..

The default is true.

If this property is true, the applications quits when the last visible primary window (i.e. window with no parent) with the Qt.WA_QuitOnClose attribute set is closed. By default this attribute is set for all widgets except for sub-windows. Refer to Qt.WindowType for a detailed list of Qt.Window objects.

See also

PySide.QtCore.QCoreApplication.quit() QWidget.close()

static PySide.QtGui.QApplication.restoreOverrideCursor()

Undoes the last PySide.QtGui.QApplication.setOverrideCursor() .

If PySide.QtGui.QApplication.setOverrideCursor() has been called twice, calling PySide.QtGui.QApplication.restoreOverrideCursor() will activate the first cursor set. Calling this function a second time restores the original widgets’ cursors.

PySide.QtGui.QApplication.saveState(sm)
Parameters:smPySide.QtGui.QSessionManager

This function deals with session management . It is invoked when the session manager wants the application to preserve its state for a future session.

For example, a text editor would create a temporary file that includes the current contents of its edit buffers, the location of the cursor and other aspects of the current editing session.

You should never exit the application within this function. Instead, the session manager may or may not do this afterwards, depending on the context. Futhermore, most session managers will very likely request a saved state immediately after the application has been started. This permits the session manager to learn about the application’s restart policy.

Warning

Within this function, no user interaction is possible, unless you ask the manager for explicit permission. See QSessionManager.allowsInteraction() and QSessionManager.allowsErrorInteraction() for details.

PySide.QtGui.QApplication.saveStateRequest(sessionManager)
Parameters:sessionManagerPySide.QtGui.QSessionManager
PySide.QtGui.QApplication.sessionId()
Return type:unicode

Returns the current session’s identifier.

If the application has been restored from an earlier session, this identifier is the same as it was in that previous session. The session identifier is guaranteed to be unique both for different applications and for different instances of the same application.

PySide.QtGui.QApplication.sessionKey()
Return type:unicode

Returns the session key in the current session .

If the application has been restored from an earlier session, this key is the same as it was when the previous session ended.

The session key changes with every call of PySide.QtGui.QApplication.commitData() or PySide.QtGui.QApplication.saveState() .

static PySide.QtGui.QApplication.setActiveWindow(act)
Parameters:actPySide.QtGui.QWidget

Sets the active window to the active widget in response to a system event. The function is called from the platform specific event handlers.

Warning

This function does not set the keyboard focus to the active widget. Call QWidget.activateWindow() instead.

It sets the PySide.QtGui.QApplication.activeWindow() and PySide.QtGui.QApplication.focusWidget() attributes and sends proper WindowActivate / WindowDeactivate and FocusIn / FocusOut events to all appropriate widgets. The window will then be painted in active state (e.g. cursors in line edits will blink), and it will have tool tips enabled.

PySide.QtGui.QApplication.setAutoSipEnabled(enabled)
Parameters:enabledPySide.QtCore.bool

This property holds toggles automatic SIP (software input panel) visibility.

Set this property to true to automatically display the SIP when entering widgets that accept keyboard input. This property only affects widgets with the WA_InputMethodEnabled attribute set, and is typically used to launch a virtual keyboard on devices which have very few or no keys.

The property only has an effect on platforms which use software input panels, such as Windows CE and Symbian.

The default is platform dependent.

static PySide.QtGui.QApplication.setColorSpec(arg__1)
Parameters:arg__1PySide.QtCore.int

Sets the color specification for the application to spec .

The color specification controls how the application allocates colors when run on a display with a limited amount of colors, e.g. 8 bit / 256 color displays.

The color specification must be set before you create the PySide.QtGui.QApplication object.

The options are:

Be aware that the CustomColor and ManyColor choices may lead to colormap flashing: The foreground application gets (most) of the available colors, while the background windows will look less attractive.

Example:

def main():
    QApplication.setColorSpec(QApplication.ManyColor)
    QApplication app(sys.argv)
    ...
    return app.exec_()
static PySide.QtGui.QApplication.setCursorFlashTime(arg__1)
Parameters:arg__1PySide.QtCore.int

This property holds the text cursor’s flash (blink) time in milliseconds.

The flash time is the time required to display, invert and restore the caret display. Usually the text cursor is displayed for half the cursor flash time, then hidden for the same amount of time, but this may vary.

The default value on X11 is 1000 milliseconds. On Windows, the Control Panel value is used and setting this property sets the cursor flash time for all applications.

We recommend that widgets do not cache this value as it may change at any time if the user changes the global desktop settings.

static PySide.QtGui.QApplication.setDesktopSettingsAware(arg__1)
Parameters:arg__1PySide.QtCore.bool

Sets whether Qt should use the system’s standard colors, fonts, etc., to on . By default, this is true.

This function must be called before creating the PySide.QtGui.QApplication object, like this:

if __name__ == '__main__':
    QApplication.setDesktopSettingsAware(False)
    app = QApplication(sys.argv)
    # ...
    return app.exec_()
static PySide.QtGui.QApplication.setDoubleClickInterval(arg__1)
Parameters:arg__1PySide.QtCore.int

This property holds the time limit in milliseconds that distinguishes a double click from two consecutive mouse clicks.

The default value on X11 is 400 milliseconds. On Windows and Mac OS, the operating system’s value is used. However, on Windows and Symbian OS, calling this function sets the double click interval for all applications.

static PySide.QtGui.QApplication.setEffectEnabled(arg__1[, enable=true])
Parameters:
  • arg__1PySide.QtCore.Qt.UIEffect
  • enablePySide.QtCore.bool
static PySide.QtGui.QApplication.setFont(arg__1[, className=0])
Parameters:

Changes the default application font to font . If className is passed, the change applies only to classes that inherit className (as reported by QObject.inherits() ).

On application start-up, the default font depends on the window system. It can vary depending on both the window system version and the locale. This function lets you override the default font; but overriding may be a bad idea because, for example, some locales need extra large fonts to support their special characters.

Warning

Do not use this function in conjunction with Qt Style Sheets . The font of an application can be customized using the “font” style sheet property. To set a bold font for all QPushButtons, set the application PySide.QtGui.QApplication.styleSheet() as ” PySide.QtGui.QPushButton { font: bold }”

static PySide.QtGui.QApplication.setGlobalStrut(arg__1)
Parameters:arg__1PySide.QtCore.QSize

This property holds the minimum size that any GUI element that the user can interact with should have.

For example, no button should be resized to be smaller than the global strut size. The strut size should be considered when reimplementing GUI controls that may be used on touch-screens or similar I/O devices.

Example:

class MyWidget (QWidget):
    # ...
    def sizeHint(self):
        return QSize(80, 25).expandedTo(QApplication.globalStrut())

By default, this property contains a PySide.QtCore.QSize object with zero width and height.

static PySide.QtGui.QApplication.setGraphicsSystem(arg__1)
Parameters:arg__1 – unicode

Sets the default graphics backend to system , which will be used for on-screen widgets and QPixmaps. The available systems are "native" , "raster" and "opengl" .

There are several ways to set the graphics backend, in order of decreasing precedence:

  • the application commandline -graphicssystem switch
  • QApplication.setGraphicsSystem()
  • the QT_GRAPHICSSYSTEM environment variable
  • the Qt configure -graphicssystem switch

If the highest precedence switch sets an invalid name, the error will be ignored and the default backend will be used.

Warning

This function is only effective before the PySide.QtGui.QApplication constructor is called.

Note

The "opengl" option is currently experimental.

PySide.QtGui.QApplication.setInputContext(arg__1)
Parameters:arg__1PySide.QtGui.QInputContext

This function replaces the PySide.QtGui.QInputContext instance used by the application with inputContext .

Qt takes ownership of the given inputContext .

static PySide.QtGui.QApplication.setKeyboardInputInterval(arg__1)
Parameters:arg__1PySide.QtCore.int

This property holds the time limit in milliseconds that distinguishes a key press from two consecutive key presses.

The default value on X11 is 400 milliseconds. On Windows and Mac OS, the operating system’s value is used.

static PySide.QtGui.QApplication.setLayoutDirection(direction)
Parameters:directionPySide.QtCore.Qt.LayoutDirection

This property holds the default layout direction for this application.

On system start-up, the default layout direction depends on the application’s language.

static PySide.QtGui.QApplication.setOverrideCursor(arg__1)
Parameters:arg__1PySide.QtGui.QCursor

Sets the application override cursor to cursor .

Application override cursors are intended for showing the user that the application is in a special state, for example during an operation that might take some time.

This cursor will be displayed in all the application’s widgets until PySide.QtGui.QApplication.restoreOverrideCursor() or another PySide.QtGui.QApplication.setOverrideCursor() is called.

Application cursors are stored on an internal stack. PySide.QtGui.QApplication.setOverrideCursor() pushes the cursor onto the stack, and PySide.QtGui.QApplication.restoreOverrideCursor() pops the active cursor off the stack. PySide.QtGui.QApplication.changeOverrideCursor() changes the curently active application override cursor.

Every PySide.QtGui.QApplication.setOverrideCursor() must eventually be followed by a corresponding PySide.QtGui.QApplication.restoreOverrideCursor() , otherwise the stack will never be emptied.

Example:

QApplication.setOverrideCursor(QCursor(Qt.WaitCursor))
calculateHugeMandelbrot()              # lunch time...
QApplication.restoreOverrideCursor()
static PySide.QtGui.QApplication.setPalette(arg__1[, className=0])
Parameters:

Changes the default application palette to palette .

If className is passed, the change applies only to widgets that inherit className (as reported by QObject.inherits() ). If className is left 0, the change affects all widgets, thus overriding any previously set class specific palettes.

The palette may be changed according to the current GUI style in QStyle.polish() .

Warning

Do not use this function in conjunction with Qt Style Sheets . When using style sheets, the palette of a widget can be customized using the “color”, “background-color”, “selection-color”, “selection-background-color” and “alternate-background-color”.

Note

Some styles do not use the palette for all drawing, for instance, if they make use of native theme engines. This is the case for the Windows XP, Windows Vista, and Mac OS X styles.

static PySide.QtGui.QApplication.setQuitOnLastWindowClosed(quit)
Parameters:quitPySide.QtCore.bool

This property holds whether the application implicitly quits when the last window is closed..

The default is true.

If this property is true, the applications quits when the last visible primary window (i.e. window with no parent) with the Qt.WA_QuitOnClose attribute set is closed. By default this attribute is set for all widgets except for sub-windows. Refer to Qt.WindowType for a detailed list of Qt.Window objects.

See also

PySide.QtCore.QCoreApplication.quit() QWidget.close()

static PySide.QtGui.QApplication.setStartDragDistance(l)
Parameters:lPySide.QtCore.int

If you support drag and drop in your application, and want to start a drag and drop operation after the user has moved the cursor a certain distance with a button held down, you should use this property’s value as the minimum distance required.

For example, if the mouse position of the click is stored in startPos and the current position (e.g. in the mouse move event) is currentPos , you can find out if a drag should be started with code like this:

if (startPos - currentPos).manhattanLength() >= QApplication.startDragDistance():
    startTheDrag()

Qt uses this value internally, e.g. in PySide.QtGui.QFileDialog .

The default value is 4 pixels.

See also

PySide.QtGui.QApplication.startDragTime() QPoint.manhattanLength() Drag and Drop

static PySide.QtGui.QApplication.setStartDragTime(ms)
Parameters:msPySide.QtCore.int

This property holds the time in milliseconds that a mouse button must be held down before a drag and drop operation will begin.

If you support drag and drop in your application, and want to start a drag and drop operation after the user has held down a mouse button for a certain amount of time, you should use this property’s value as the delay.

Qt also uses this delay internally, e.g. in PySide.QtGui.QTextEdit and PySide.QtGui.QLineEdit , for starting a drag.

The default value is 500 ms.

static PySide.QtGui.QApplication.setStyle(arg__1)
Parameters:arg__1 – unicode
Return type:PySide.QtGui.QStyle

This is an overloaded function.

Requests a PySide.QtGui.QStyle object for style from the PySide.QtGui.QStyleFactory .

The string must be one of the QStyleFactory.keys() , typically one of “windows”, “motif”, “cde”, “plastique”, “windowsxp”, or “macintosh”. Style names are case insensitive.

Returns 0 if an unknown style is passed, otherwise the PySide.QtGui.QStyle object returned is set as the application’s GUI style.

Warning

To ensure that the application’s style is set correctly, it is best to call this function before the PySide.QtGui.QApplication constructor, if possible.

static PySide.QtGui.QApplication.setStyle(arg__1)
Parameters:arg__1PySide.QtGui.QStyle

Sets the application’s GUI style to style . Ownership of the style object is transferred to PySide.QtGui.QApplication , so PySide.QtGui.QApplication will delete the style object on application exit or when a new style is set and the old style is still the parent of the application object.

Example usage:

QApplication.setStyle(QWindowsStyle())

When switching application styles, the color palette is set back to the initial colors or the system defaults. This is necessary since certain styles have to adapt the color palette to be fully style-guide compliant.

Setting the style before a palette has been se, i.e., before creating PySide.QtGui.QApplication , will cause the application to use QStyle.standardPalette() for the palette.

Warning

Qt style sheets are currently not supported for custom PySide.QtGui.QStyle subclasses. We plan to address this in some future release.

PySide.QtGui.QApplication.setStyleSheet(sheet)
Parameters:sheet – unicode

This property holds the application style sheet.

By default, this property returns an empty string unless the user specifies the -stylesheet option on the command line when running the application.

See also

QWidget.setStyle() Qt Style Sheets

static PySide.QtGui.QApplication.setWheelScrollLines(arg__1)
Parameters:arg__1PySide.QtCore.int

This property holds the number of lines to scroll a widget, when the mouse wheel is rotated..

If the value exceeds the widget’s number of visible lines, the widget should interpret the scroll operation as a single page up or page down . If the widget is an item view class , then the result of scrolling one line depends on the setting of the widget’s scroll mode . Scroll one line can mean scroll one item or scroll one pixel .

By default, this property has a value of 3.

static PySide.QtGui.QApplication.setWindowIcon(icon)
Parameters:iconPySide.QtGui.QIcon

This property holds the default window icon.

See also

QWidget.setWindowIcon() Setting the Application Icon

static PySide.QtGui.QApplication.startDragDistance()
Return type:PySide.QtCore.int

If you support drag and drop in your application, and want to start a drag and drop operation after the user has moved the cursor a certain distance with a button held down, you should use this property’s value as the minimum distance required.

For example, if the mouse position of the click is stored in startPos and the current position (e.g. in the mouse move event) is currentPos , you can find out if a drag should be started with code like this:

if (startPos - currentPos).manhattanLength() >= QApplication.startDragDistance():
    startTheDrag()

Qt uses this value internally, e.g. in PySide.QtGui.QFileDialog .

The default value is 4 pixels.

See also

PySide.QtGui.QApplication.startDragTime() QPoint.manhattanLength() Drag and Drop

static PySide.QtGui.QApplication.startDragTime()
Return type:PySide.QtCore.int

This property holds the time in milliseconds that a mouse button must be held down before a drag and drop operation will begin.

If you support drag and drop in your application, and want to start a drag and drop operation after the user has held down a mouse button for a certain amount of time, you should use this property’s value as the delay.

Qt also uses this delay internally, e.g. in PySide.QtGui.QTextEdit and PySide.QtGui.QLineEdit , for starting a drag.

The default value is 500 ms.

static PySide.QtGui.QApplication.style()
Return type:PySide.QtGui.QStyle

Returns the application’s style object.

PySide.QtGui.QApplication.styleSheet()
Return type:unicode

This property holds the application style sheet.

By default, this property returns an empty string unless the user specifies the -stylesheet option on the command line when running the application.

See also

QWidget.setStyle() Qt Style Sheets

static PySide.QtGui.QApplication.syncX()

Synchronizes with the X server in the X11 implementation. This normally takes some time. Does nothing on other platforms.

static PySide.QtGui.QApplication.topLevelAt(x, y)
Parameters:
  • xPySide.QtCore.int
  • yPySide.QtCore.int
Return type:

PySide.QtGui.QWidget

This is an overloaded function.

Returns the top-level widget at the point (x , y ); returns 0 if there is no such widget.

static PySide.QtGui.QApplication.topLevelAt(p)
Parameters:pPySide.QtCore.QPoint
Return type:PySide.QtGui.QWidget

Returns the top-level widget at the given point ; returns 0 if there is no such widget.

static PySide.QtGui.QApplication.topLevelWidgets()
Return type:

Returns a list of the top-level widgets (windows) in the application.

Note

Some of the top-level widgets may be hidden, for example a tooltip if no tooltip is currently shown.

Example:

def showAllHiddenTopLevelWidgets():
    for widget in QApplication.topLevelWidgets():
        if widget.isHidden():
            widget.show()
static PySide.QtGui.QApplication.type()
Return type:PySide.QtGui.QApplication.Type

Returns the type of application ( Tty , GuiClient , or GuiServer ). The type is set when constructing the PySide.QtGui.QApplication object.

static PySide.QtGui.QApplication.wheelScrollLines()
Return type:PySide.QtCore.int

This property holds the number of lines to scroll a widget, when the mouse wheel is rotated..

If the value exceeds the widget’s number of visible lines, the widget should interpret the scroll operation as a single page up or page down . If the widget is an item view class , then the result of scrolling one line depends on the setting of the widget’s scroll mode . Scroll one line can mean scroll one item or scroll one pixel .

By default, this property has a value of 3.

static PySide.QtGui.QApplication.widgetAt(x, y)
Parameters:
  • xPySide.QtCore.int
  • yPySide.QtCore.int
Return type:

PySide.QtGui.QWidget

This is an overloaded function.

Returns the widget at global screen position (x , y ), or 0 if there is no Qt widget there.

static PySide.QtGui.QApplication.widgetAt(p)
Parameters:pPySide.QtCore.QPoint
Return type:PySide.QtGui.QWidget

Returns the widget at global screen position point , or 0 if there is no Qt widget there.

This function can be slow.

static PySide.QtGui.QApplication.windowIcon()
Return type:PySide.QtGui.QIcon

This property holds the default window icon.

See also

QWidget.setWindowIcon() Setting the Application Icon