bool MainWindow::eventFilter( QObject * object, QEvent * event )
{
QScrollArea * scrollArea = ui->scrollArea;
if ( object == scrollArea )
{
if ( event->type() == QEvent::MouseButtonPress )
{
QMouseEvent * mouseEvent = static_cast < QMouseEvent * > ( event );
if ( mouseEvent->button() == Qt::LeftButton )
{
lastPos = mouseEvent->pos();
if( scrollArea->horizontalScrollBar()->isVisible() || scrollArea->verticalScrollBar()->isVisible() )
scrollArea->setCursor( Qt::ClosedHandCursor );
else
scrollArea->setCursor( Qt::ArrowCursor );
}
}else if ( event->type() == QEvent::MouseMove )
{
QMouseEvent *mouseEvent = static_cast < QMouseEvent * > ( event );
if ( mouseEvent->buttons() == Qt::LeftButton )
{
lastPos -= mouseEvent->pos();
int hValue = scrollArea->horizontalScrollBar()->value();
int vValue = scrollArea->verticalScrollBar()->value();
scrollArea->horizontalScrollBar()->setValue( lastPos.x() + hValue );
scrollArea->verticalScrollBar()->setValue( lastPos.y() + vValue );
lastPos = mouseEvent->pos();
}
}else if ( event->type() == QEvent::MouseButtonRelease )
scrollArea->setCursor( Qt::ArrowCursor );
}
return QWidget::eventFilter(object, event);
}
