import sys
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
class ShapeWidget(QWidget):
  def __init__(self,parent=None):
    super(ShapeWidget, self).__init__(parent)
    self.i=1
    self.mypix()
    self.timer=QTimer()
    self.timer.setInterval(500)
    self.timer.timeout.connect(self.timeChanged)
    self.timer.start()
  #显示不规则图片
  def mypix(self):
    self.update()
    if self.i==5:
      self.i=1
    self.mypic={1:'./images/left.png',2:'./images/up.png',3:'./images/right.png',4:'./images/down.png'}
    self.pix=QPixmap(self.mypic[self.i],'0',Qt.AvoidDither|Qt.ThresholdAlphaDither|Qt.ThresholdDither)
    self.resize(self.pix.size())
    self.setMask(self.pix.mask())
    self.dragPosition=None
  def mousePressEvent(self, QMouseEvent):
    if QMouseEvent.button()==Qt.LeftButton:
      self.m_drag=True
      self.m_DragPosition=QMouseEvent.globalPos()-self.pos()
      QMouseEvent.accept()
      self.setCursor(QCursor(Qt.OpenHandCursor))
  def mouseMoveEvent(self, QMouseEvent):
    if Qt.LeftButton and self.m_drag:
      self.move(QMouseEvent.globalPos()-self.m_DragPosition)
      QMouseEvent.accept()
  def mouseReleaseEvent(self, QMouseEvent):
    self.m_drag=False
    self.setCursor(QCursor(Qt.ArrowCursor))
  def paintEvent(self, QPaintEvent):
    painter=QPainter(self)
    painter.drawPixmap(0,0,self.pix.width(),self.pix.height(),self.pix)
  def mouseDoubleClickEvent(self, QMouseEvent):
    if QMouseEvent.button()==1:
      self.i+=1
      self.mypix()
  def timeChanged(self):
    self.i+=1
    self.mypix()
if __name__ == '__main__':
  app=QApplication(sys.argv)
  form=ShapeWidget()
  form.show()
  sys.exit(app.exec_())