python pyqt5 事件过滤器

    self.label1 = QLabel("请点击")
    self.label2 = QLabel("请点击")
    self.label3 = QLabel("请点击")
    self.LabelState = QLabel("test")

    self.image1 = QImage("images/cartoon1.ico")
    self.image2 = QImage("images/cartoon1.ico")
    self.image3 = QImage("images/cartoon1.ico")

    self.width = 600
    self.height = 300

    self.resize(self.width, self.height)

    self.label1.installEventFilter(self)
    self.label2.installEventFilter(self)
    self.label3.installEventFilter(self)

    mainLayout = QGridLayout(self)
    mainLayout.addWidget(self.label1, 500, 0)
    mainLayout.addWidget(self.label2, 500, 1)
    mainLayout.addWidget(self.label3, 500, 2)
    mainLayout.addWidget(self.LabelState, 600, 1)
    self.setLayout(mainLayout)

def eventFilter(self, watched, event):
    if watched == self.label1: # 只对label1的点击事件进行过滤，重写其行为，其他的事件会被忽略
        if event.type() == QEvent.MouseButtonPress: # 这里对鼠标按下事件进行过滤，重写其行为
            mouseEvent = QMouseEvent(event)
            if mouseEvent.buttons() == Qt.LeftButton:
                self.LabelState.setText("按下鼠标左键")
            elif mouseEvent.buttons() == Qt.MidButton:
                self.LabelState.setText("按下鼠标中间键")
            elif mouseEvent.buttons() == Qt.RightButton:
                self.LabelState.setText("按下鼠标右键")

            '''转换图片大小'''
            transform = QTransform()
            transform.scale(0.5, 0.5)
            tmp = self.image1.transformed(transform)
            self.label1.setPixmap(QPixmap.fromImage(tmp))
        if event.type() == QEvent.MouseButtonRelease: # 这里对鼠标释放事件进行过滤，重写其行为
            self.LabelState.setText("释放鼠标按钮")
            self.label1.setPixmap(QPixmap.fromImage(self.image1))
    return QDialog.eventFilter(self, watched, event) # 其他情况会返回系统默认的事件处理方法。