Tukukkk

I want to use my qlabel as a countdown. Basically when countdown is called the label changes " 3 2 1 begin", with 1 second gap in-between .

however, if I do this:

def nextSound(self):



    self.mainLabel.setText("3")



    sleep(1)



    self.mainLabel.setText("2")



    sleep(1)

    self.mainLabel.setText("1")

it simply just wait until the end without updating the label. So I try to use QPropertyAnimation:

  def nextSound(self):



        self.animate = QPropertyAnimation(self.mainLabel,"setText")



        self.animate.setDuration(1000)

        self.animate.startValue("3")

        self.animate.setEndValue("2")

        self.animate.start()

But received this error:

self.animate = QPropertyAnimation(self.mainLabel,"setText")

TypeError: arguments did not match any overloaded call:

  QPropertyAnimation(parent: QObject = None): too many arguments

  QPropertyAnimation(QObject, Union[QByteArray, bytes, bytearray], parent: QObject = None): argument 2 has unexpected type 'str'

Any suggestion? Thanks

QPropertyAnimation is based on interpolating the values that a q-property takes, when wanting to use setText I think that the closest thing is the q-property text but the texts can not be interpolated so a solution would be to create a q-property that takes numerical value.

from PyQt5 import QtCore, QtWidgets



class NumLabel(QtWidgets.QLabel):

    def number(self):

        try:

            return int(self.text())

        except:

            return 0

    def setNumber(self, number):

        self.setNum(number)

    number = QtCore.pyqtProperty(int, fget=number, fset=setNumber)



if __name__ == '__main__':

    import sys

    app = QtWidgets.QApplication(sys.argv)

    w = NumLabel(alignment=QtCore.Qt.AlignCenter)

    w.resize(640, 480)

    animation = QtCore.QPropertyAnimation(w, b'number')

    animation.setStartValue(3)

    animation.setEndValue(0)

    animation.setDuration(1000*(abs(animation.endValue() - animation.startValue())))

    animation.start()

    w.show()

    sys.exit(app.exec_())

Another best option is to use QTimeLine:

from PyQt5 import QtCore, QtWidgets



if __name__ == '__main__':

    import sys

    app = QtWidgets.QApplication(sys.argv)

    w = QtWidgets.QLabel(alignment=QtCore.Qt.AlignCenter)

    w.resize(640, 480)

    start = 3

    end = 0

    timeLine = QtCore.QTimeLine(abs(end - start)*1000, w)

    timeLine.setFrameRange(start, end)

    timeLine.frameChanged.connect(w.setNum)



    # set start value

    w.setNum(start)

    # start timer

    timeLine.start()



    w.show()

    sys.exit(app.exec_())