QGraphicsItem鼠标大小缩放

#include "MyItem.h" MyItem::MyItem() { m_rect=QRectF(-60,-60,120,120); setZValue(0); setAcceptDrops(true); setFlags(ItemIsSelectable); setAcceptsHoverEvents(true); cScale=false; m_cursor=new QCursor; direction=0; } void MyItem::ResetRect(QRectF rect){ m_rect=rect; update(boundingRect()); } QRectF MyItem::boundingRect()const{ return QRectF(m_rect.x()-2,m_rect.y()-2,m_rect.width()+4,m_rect.height()+4); } QPainterPath MyItem::shape()const{ QPainterPath path; path.addRect(m_rect); return path; } void MyItem::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget){ Q_UNUSED(option); Q_UNUSED(widget); painter->drawRect(m_rect); } void MyItem::hoverEnterEvent(QGraphicsSceneHoverEvent *event){ QPointF pos1=event->scenePos(); QPointF lt=this->scenePos()+QPointF(m_rect.x(),m_rect.y()); QPointF lb=this->scenePos()+QPointF(m_rect.x(),m_rect.y()+m_rect.height()); QPointF rt=this->scenePos()+QPointF(m_rect.x()+m_rect.width(),m_rect.y()); QPointF rb=this->scenePos()+QPointF(m_rect.x()+m_rect.width(),m_rect.y()+m_rect.height()); if((pos1.x()<=lt.x()+2&&pos1.y()<=lt.y()+2) ||(pos1.x()>=rb.x()-2&&pos1.y()>=rb.y()-2)){ m_cursor->setShape(Qt::SizeFDiagCursor); if(pos1.x()<=lt.x()+2)direction=8; else direction=4; }else if((pos1.x()<=lb.x()+2&&pos1.y()>=lb.y()-2) ||(pos1.x()>=rt.x()-2&&pos1.y()<=rt.y()+2)){ m_cursor->setShape(Qt::SizeBDiagCursor); if(pos1.x()<=lb.x()+2)direction=6; else direction=2; }else if((pos1.x()<=lt.x()+2||pos1.x()>=rt.x()-2) &&(pos1.y()<=lb.y()&&pos1.y()>=lt.y())){ m_cursor->setShape(Qt::SizeHorCursor); if(pos1.x()<=lt.x()+2)direction=7; else direction=3; }else if((pos1.y()<=lt.y()+2||pos1.y()>=lb.y()-2) &&(pos1.x()>=lt.x()&&pos1.x()<=rt.x())){ m_cursor->setShape(Qt::SizeVerCursor); if(pos1.y()<=lt.y()+2)direction=1; else direction=5; }else{ cScale=false; m_cursor->setShape(Qt::ArrowCursor); } this->setCursor(*m_cursor); update(); QGraphicsItem::hoverEnterEvent(event); } void MyItem::hoverMoveEvent(QGraphicsSceneHoverEvent *event){ QPointF pos1=event->scenePos(); QPointF lt=this->scenePos()+QPointF(m_rect.x(),m_rect.y()); QPointF lb=this->scenePos()+QPointF(m_rect.x(),m_rect.y()+m_rect.height()); QPointF rt=this->scenePos()+QPointF(m_rect.x()+m_rect.width(),m_rect.y()); QPointF rb=this->scenePos()+QPointF(m_rect.x()+m_rect.width(),m_rect.y()+m_rect.height()); if((pos1.x()<=lt.x()+2&&pos1.y()<=lt.y()+2) ||(pos1.x()>=rb.x()-2&&pos1.y()>=rb.y()-2)){ m_cursor->setShape(Qt::SizeFDiagCursor); if(pos1.x()<=lt.x()+2)direction=8; else direction=4; }else if((pos1.x()<=lb.x()+2&&pos1.y()>=lb.y()-2) ||(pos1.x()>=rt.x()-2&&pos1.y()<=rt.y()+2)){ m_cursor->setShape(Qt::SizeBDiagCursor); if(pos1.x()<=lb.x()+2)direction=6; else direction=2; }else if((pos1.x()<=lt.x()+2||pos1.x()>=rt.x()-2) &&(pos1.y()<=lb.y()&&pos1.y()>=lt.y())){ m_cursor->setShape(Qt::SizeHorCursor); if(pos1.x()<=lt.x()+2)direction=7; else direction=3; }else if((pos1.y()<=lt.y()+2||pos1.y()>=lb.y()-2) &&(pos1.x()>=lt.x()&&pos1.x()<=rt.x())){ m_cursor->setShape(Qt::SizeVerCursor); if(pos1.y()<=lt.y()+2)direction=1; else direction=5; }else{ cScale=false; m_cursor->setShape(Qt::ArrowCursor); } this->setCursor(*m_cursor); update(); QGraphicsItem::hoverMoveEvent(event); } void MyItem::hoverLeaveEvent(QGraphicsSceneHoverEvent *event){ m_cursor->setShape(Qt::ArrowCursor); cScale=false; this->setCursor(*m_cursor); update(); QGraphicsItem::hoverLeaveEvent(event); } void MyItem::mousePressEvent(QGraphicsSceneMouseEvent *event){ if(event->button()==Qt::LeftButton){ start=event->scenePos(); cScale=true; } update(); QGraphicsItem::mousePressEvent(event); } void MyItem::mouseMoveEvent(QGraphicsSceneMouseEvent *event){ int t=0; t++; t--; if(cScale){ QPointF dis; end=event->scenePos(); dis=end-start; start=end; switch(direction){ case 1: { QRectF tem=QRectF(m_rect.x(),m_rect.y()+dis.y()/2,m_rect.width(),m_rect.height()-dis.y()); this->ResetRect(tem); update(boundingRect()); this->moveBy(0,dis.y()/2); break; } case 2: { QRectF tem=QRectF(m_rect.x()+dis.x()/2,m_rect.y()+dis.y()/2, m_rect.width()+dis.x(),m_rect.height()-dis.y()); this->ResetRect(tem); update(boundingRect()); this->moveBy(-dis.x()/2,-dis.y()/2); break; } case 3: { QRectF tem=QRectF(m_rect.x()+dis.x()/2,m_rect.y(),m_rect.width()+dis.x(),m_rect.height()); this->ResetRect(tem); update(boundingRect()); this->moveBy(-dis.x()/2,0); break; } case 4: { QRectF tem=QRectF(m_rect.x()+dis.x()/2,m_rect.y()+dis.y()/2, m_rect.width()+dis.x(),m_rect.height()+dis.y()); this->ResetRect(tem); update(boundingRect()); this->moveBy(-dis.x()/2,-dis.y()/2); break; } case 5: { QRectF tem=QRectF(m_rect.x(),m_rect.y()+dis.y()/2,m_rect.width(),m_rect.height()+dis.y()); this->ResetRect(tem); update(boundingRect()); this->moveBy(0,-dis.y()/2); break; } case 6: { QRectF tem=QRectF(m_rect.x()+dis.x()/2,m_rect.y()+dis.y()/2, m_rect.width()-dis.x(),m_rect.height()+dis.y()); this->ResetRect(tem); update(boundingRect()); this->moveBy(-dis.x()/2,-dis.y()/2); break; } case 7: { QRectF tem=QRectF(m_rect.x()+dis.x()/2,m_rect.y(),m_rect.width()-dis.x(),m_rect.height()); this->ResetRect(tem); update(boundingRect()); this->moveBy(dis.x()/2,0); break; } case 8: { QRectF tem=QRectF(m_rect.x()+dis.x()/2,m_rect.y()+dis.y()/2, m_rect.width()-dis.x(),m_rect.height()-dis.y()); this->ResetRect(tem); update(boundingRect()); this->moveBy(dis.x()/2,dis.y()/2); break; } } } update(); QGraphicsItem::mouseMoveEvent(event); } void MyItem::mouseReleaseEvent(QGraphicsSceneMouseEvent *event){ cScale=false; update(); QGraphicsItem::mouseReleaseEvent(event); }