QWidget::setMask()QStyleQStyleHintReturnMask
QPixmap pxPicture( "picture.png");QToolButton newTb;newTb.resize( pxPicture.size() );newTb.setUsesBigPixmap( true );newTb.setMask( pxPicture.createHeuristicMask() );newTb.setPixmap( pxPicture );newTb.show();
QMainWindow mw; QWidget central(&mw); QPixmap pxPicture( "IceFriend.png"); QToolButton newTb(¢ral); newTb.resize( pxPicture.size() ); newTb.setMask( pxPicture.createHeuristicMask() ); newTb.setIcon( pxPicture ); newTb.setIconSize( pxPicture.size() ); newTb.show(); QObject::connect(&newTb, SIGNAL(clicked()), &app, SLOT(quit())); mw.setCentralWidget(¢ral); mw.show();