the timer can not be connected to the slot in pyqt5

Question

I can not connect the timer to the move() slot timer.timeout.connect( self.move) this is not working but QtCore.QTimer.singleShot(50, self.move) this is just working one step not more.

class Bullet(QGraphicsRectItem):
    def __init__(self):
        super().__init__()

        self.setRect(0,0,10,50)

        #timer = QTimer()
        #timer.timeout.connect( self.move)
        #timer.start(50)
        QtCore.QTimer.singleShot(50, self.move)

    def move(self):
        print("Timer Clicked")
        self.setPos(self.x(), self.y()-10)

Answer 1

the problem is simple, a variable created in a function is local and will be eliminated when the function is finished, therefore the signal does not fire, instead the QTimer.singleShot() has a global scope, the solution is to extend the scope of the timer, for this you must make it a member of the class.

class Bullet(QGraphicsRectItem):
    def __init__(self):
        super().__init__()

        self.setRect(0,0,10,50)

        self.timer = QTimer()
        self.timer.timeout.connect(self.move)
        self.timer.start(50)

    def move(self):
        print("Timer Clicked")
        self.setPos(self.x(), self.y()-10)