Qt实现苹果状态切换按钮

#include "button.h"
#include <qdebug>
 
button::button(qwidget *parent) :
 qpushbutton(parent)
{
 status = 0;
 span_length = 0;
 rl_flag = false;
 release_flag =true;
 timeline = new qtimeline;
 connect(timeline,signal(framechanged(int)),this,slot(timeout(int)));
}
 
void button::paintevent(qpaintevent *e)
{
 qpainter painter(this);
 painter.setrenderhint(qpainter::antialiasing, true);
 qpen pen;
 pen.setwidth(2);
 pen.setcolor(qcolor(219,219,219));
 painter.setpen(pen);
 painter.setbrush(qt::green);
 painter.drawroundedrect(1,1,this->width()-2,this->height()-2,30,30);
 
 painter.setbrush(qt::white);
 painter.setpen(pen);
 
 if(!rl_flag){
  switch(status)
  {
  case 0:painter.drawellipse(1,1,this->height()-3,this->height()-3);break;
  case 1:painter.drawroundedrect(1,1,span_length,this->height()-2,30,30);break;
  case 2:painter.drawellipse(this->width()+3-this->height(),1,this->height()-3,this->height()-3);rl_flag=true;status=0;break;
  }
 }else{
  switch(status)
  {
  case 0:painter.drawellipse(this->width()+3-this->height(),1,this->height()-3,this->height()-3);break;
  case 1:painter.drawroundedrect(this->width()-1-span_length,1,span_length,this->height()-2,30,30);break;
  case 2:painter.drawellipse(1,1,this->height()-3,this->height()-3);rl_flag=false;status=0;break;
  }
 }
}
 
void button::drawspan(qpainter painter,int s)
{
 
}
 
void button::mousepressevent(qmouseevent *e)
{
 timeline->setduration(400);
 span_length = 0;
 status=1;
 if(!rl_flag){
  int r1 = this->height()-3;
  int r2 = (this->width()/4*3)>r1?(this->width()/4*3):r1;
  timeline->setframerange(r1,r2);
 }else{
  int r1 = this->height()-3;
  int r2 = (this->width()/4*3)>r1?(this->width()/4*3):r1;//(this->width()/4*1)>r1?(this->width()/4*1):r1;
  timeline->setframerange(r1,r2);
 }
 timeline->start();
}
 
void button::mousemoveevent(qmouseevent *e)
{
}
 
void button::mousereleaseevent(qmouseevent *e)
{
 timeline->stop();
 status = 2;
 update();
}
 
void button::timeout(int x)
{
 status = 1;
 span_length = x;
 update();
}