Qt Reference Documentation

Contents

Q3WidgetStack Class Reference

The Q3WidgetStack class provides a stack of widgets of which only the top widget is user-visible. More...

 #include <Q3WidgetStack>

This class is part of the Qt 3 support library. It is provided to keep old source code working. We strongly advise against using it in new code. See Porting to Qt 4 for more information.

Inherits: Q3Frame.

Public Functions

Q3WidgetStack ( QWidget * parent, const char * name = 0, Qt::WindowFlags f = 0 )
~Q3WidgetStack ()
int addWidget ( QWidget * w, int id = -1 )
int id ( QWidget * widget ) const
void removeWidget ( QWidget * w )
QWidget * visibleWidget () const
QWidget * widget ( int id ) const

Reimplemented Public Functions

virtual QSize minimumSizeHint () const
virtual void setVisible ( bool visible )
virtual QSize sizeHint () const

Public Slots

void raiseWidget ( int id )
void raiseWidget ( QWidget * w )

Signals

void aboutToShow ( int id )
void aboutToShow ( QWidget * widget )

Protected Functions

virtual void setChildGeometries ()

Reimplemented Protected Functions

virtual void childEvent ( QChildEvent * e )
virtual bool event ( QEvent * e )
virtual void frameChanged ()
virtual void resizeEvent ( QResizeEvent * e )

Additional Inherited Members

Detailed Description

The Q3WidgetStack class provides a stack of widgets of which only the top widget is user-visible.

The application programmer can move any widget to the top of the stack at any time using raiseWidget(), and add or remove widgets using addWidget() and removeWidget(). It is not sufficient to pass the widget stack as parent to a widget which should be inserted into the widgetstack.

visibleWidget() is the get equivalent of raiseWidget(); it returns a pointer to the widget that is currently at the top of the stack.

Q3WidgetStack also provides the ability to manipulate widgets through application-specified integer IDs. You can also translate from widget pointers to IDs using id() and from IDs to widget pointers using widget(). These numeric IDs are unique (per Q3WidgetStack, not globally), but Q3WidgetStack does not attach any additional meaning to them.

The default widget stack is frameless, but you can use the usual Q3Frame functions (such as setFrameStyle()) to add a frame.

Q3WidgetStack provides a signal, aboutToShow(), which is emitted just before a managed widget is shown.

See also Q3TabDialog, QTabWidget, QTabBar, and Q3Frame.

Member Function Documentation

Q3WidgetStack::Q3WidgetStack ( QWidget * parent, const char * name = 0, Qt::WindowFlags f = 0 )

Constructs an empty widget stack.

The parent, name and f arguments are passed to the Q3Frame constructor.

Q3WidgetStack::~Q3WidgetStack ()

Destroys the object and frees any allocated resources.

void Q3WidgetStack::aboutToShow ( int id ) [signal]

This signal is emitted just before a managed widget is shown if that managed widget has an ID != -1. The id parameter is the numeric ID of the widget.

If you call visibleWidget() in a slot connected to aboutToShow(), the widget it returns is the one that is currently visible, not the one that is about to be shown.

void Q3WidgetStack::aboutToShow ( QWidget * widget ) [signal]

This is an overloaded function.

This signal is emitted just before a managed widget is shown. The argument is a pointer to the widget.

If you call visibleWidget() in a slot connected to aboutToShow(), the widget returned is the one that is currently visible, not the one that is about to be shown.

int Q3WidgetStack::addWidget ( QWidget * w, int id = -1 )

Adds widget w to this stack of widgets, with ID id.

If you pass an id >= 0 this ID is used. If you pass an id of -1 (the default), the widgets will be numbered automatically. If you pass -2 a unique negative integer will be generated. No widget has an ID of -1. Returns the ID or -1 on failure (e.g. w is 0).

If you pass an id that is already used, then a unique negative integer will be generated to prevent two widgets having the same id.

If w already exists in the stack the widget will be removed first.

If w is not a child of this Q3WidgetStack moves it using reparent().

void Q3WidgetStack::childEvent ( QChildEvent * e ) [virtual protected]

Reimplemented from QObject::childEvent().

bool Q3WidgetStack::event ( QEvent * e ) [virtual protected]

Reimplemented from QObject::event().

void Q3WidgetStack::frameChanged () [virtual protected]

Reimplemented from Q3Frame::frameChanged().

int Q3WidgetStack::id ( QWidget * widget ) const

Returns the ID of the widget. Returns -1 if widget is 0 or is not being managed by this widget stack.

See also widget() and addWidget().

QSize Q3WidgetStack::minimumSizeHint () const [virtual]

Reimplemented from QWidget::minimumSizeHint().

void Q3WidgetStack::raiseWidget ( int id ) [slot]

Raises the widget with ID id to the top of the widget stack.

See also visibleWidget().

void Q3WidgetStack::raiseWidget ( QWidget * w ) [slot]

This is an overloaded function.

Raises widget w to the top of the widget stack.

void Q3WidgetStack::removeWidget ( QWidget * w )

Removes widget w from this stack of widgets. Does not delete w. If w is the currently visible widget, no other widget is substituted.

See also visibleWidget() and raiseWidget().

void Q3WidgetStack::resizeEvent ( QResizeEvent * e ) [virtual protected]

Reimplemented from QWidget::resizeEvent().

void Q3WidgetStack::setChildGeometries () [virtual protected]

Fixes up the children's geometries.

void Q3WidgetStack::setVisible ( bool visible ) [virtual]

Reimplemented from QWidget::setVisible().

QSize Q3WidgetStack::sizeHint () const [virtual]

Reimplemented from QWidget::sizeHint().

QWidget * Q3WidgetStack::visibleWidget () const

Returns the currently visible widget (the one at the top of the stack), or 0 if nothing is currently being shown.

See also aboutToShow(), id(), and raiseWidget().

QWidget * Q3WidgetStack::widget ( int id ) const

Returns the widget with ID id. Returns 0 if this widget stack does not manage a widget with ID id.

See also id() and addWidget().