QT滚轮滚动事件

///滚轮上下滑动
void WriteWorkOrder::wheelEvent(QWheelEvent *event)
{
    int i = ui->mainContent->height() - (this->height()-this->statusBar()->height());
   if(event->delta() > 0 && num != 0)
   {
       qDebug("滚轮向上移动 %d",num);
//move是移动函数
       ui->mainContent->move(0,num);
       num+=10;
///qAbs(）是求绝对值函数
   }else if((qAbs(num)) <= i){
       qDebug("滚轮向下移动 %d",qAbs(num));
       ui->mainContent->move(0,num);
       num-=10;
   }
}