source: trunk/src/gui/kernel/qwidgetaction.cpp@ 603

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#include "qwidgetaction.h"
#include "qdebug.h"

#ifndef QT_NO_ACTION
#include "qwidgetaction_p.h"

QT_BEGIN_NAMESPACE

/*!
    \class QWidgetAction
    \since 4.2
    \brief The QWidgetAction class extends QAction by an interface
    for inserting custom widgets into action based containers, such
    as toolbars.

    \ingroup mainwindow-classes

    Most actions in an application are represented as items in menus or
    buttons in toolbars. However sometimes more complex widgets are
    necessary. For example a zoom action in a word processor may be
    realized using a QComboBox in a QToolBar, presenting a range
    of different zoom levels. QToolBar provides QToolBar::insertWidget()
    as convenience function for inserting a single widget.
    However if you want to implement an action that uses custom
    widgets for visualization in multiple containers then you have to
    subclass QWidgetAction.

    If a QWidgetAction is added for example to a QToolBar then
    QWidgetAction::createWidget() is called. Reimplementations of that
    function should create a new custom widget with the specified parent.

    If the action is removed from a container widget then
    QWidgetAction::deleteWidget() is called with the previously created custom
    widget as argument. The default implementation hides the widget and deletes
    it using QObject::deleteLater().

    If you have only one single custom widget then you can set it as default