Qt Documentation

  • Qt 4.8
  • Qt3SupportLight
  • Q3Button

Contents

Q3Button Class

The Q3Button class is a compatibility base class of button widgets More...

Header: #include <Q3Button>
Inherits: QAbstractButton

Public Functions

Q3Button(QWidget * parent = 0, const char * name = 0, Qt::WindowFlags f = 0)
~Q3Button()

Protected Functions

virtual void drawButton(QPainter * painter)
virtual void drawButtonLabel(QPainter * painter)

Reimplemented Protected Functions

virtual void paintEvent(QPaintEvent * event)

Additional Inherited Members

Detailed Description

The Q3Button class is a compatibility base class of button widgets

In new code, use QAbstractButton.

To subclass Q3Button, you must reimplement at least drawButton() (to draw the button's outline) and drawButtonLabel() (to draw its text or pixmap). It is generally advisable to reimplement sizeHint() as well, and sometimes hitButton() (to determine whether a button press is within the button).

Member Function Documentation

Q3Button::Q3Button(QWidget * parent = 0, const char * name = 0, Qt::WindowFlags f = 0)

Constructs a standard button called name with parent parent, using the widget flags f.

Q3Button::~Q3Button()

Destroys the button.

[virtual protected] void Q3Button::drawButton(QPainter * painter)

Draws the button on the given painter. The default implementation does nothing.

This virtual function is reimplemented by subclasses to draw real buttons. At some point, these reimplementations should call drawButtonLabel().

See also drawButtonLabel() and paintEvent().

[virtual protected] void Q3Button::drawButtonLabel(QPainter * painter)

Draws the button text or pixmap on the given painter.

This virtual function is reimplemented by subclasses to draw real buttons. It is invoked by drawButton().

See also drawButton() and paintEvent().

[virtual protected] void Q3Button::paintEvent(QPaintEvent * event)

Reimplemented from QWidget::paintEvent().

Handles paint events, received in event, for buttons. Small and typically complex buttons are painted double-buffered to reduce flicker. The actually drawing is done in the virtual functions drawButton() and drawButtonLabel().

See also drawButton() and drawButtonLabel().

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