PyQt: 练习 QSlider

import sys
from PyQt5.Qt import *


class CSlider(QSlider):
    def __init__(self, *__args):
        super(CSlider, self).__init__(*__args)
        self.components()

    def components(self):
        self.label = QLabel(self)
        # self.label_position()

    def label_position(self):
        self.label.setText(str(self.value()))
        self.label.adjustSize()
        self.position = [int(round((self.width() - self.label.width()) / 2, 0)),
                         int(round(
                             (self.height() - self.label.height()) * ((self.maximum() - self.value()) / self.maximum()),
                             0))]
        self.label.move(self.position[0], self.position[1])

    def mousePressEvent(self, ev) -> None:
        self.label_position()
        return super().mousePressEvent(ev)

    # def mouseMoveEvent(self, ev) -> None:
    #     self.label_position()
    #     return super().mouseMoveEvent(ev)


class Window(QWidget):
    def __init__(self):
        super().__init__()
        self.setup_ui()

    def setup_ui(self):
        self.setWindowTitle("Qt桌面应用程序")
        self.resize(300, 300)

        self.slider = CSlider(self)
        self.slider.move(50, 50)
        self.slider.setTickPosition(QSlider.TicksBothSides)

        def value_changed(value):
            self.slider.label_position()

        self.slider.valueChanged.connect(value_changed)


if __name__ == '__main__':
    app = QApplication(sys.argv)
    window = Window()
    window.show()
    window.slider.label_position()
    sys.exit(app.exec_())