PyQt/QSplashScreen/GifSplashScreen.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-

"""
Created on 2020/6/11
@author: Irony
@site: https://pyqt.site , https://github.com/PyQt5
@email: 892768447@qq.com
@file:
@description: 
"""

from time import sleep

try:
    from PyQt5.QtCore import Qt
    from PyQt5.QtGui import QMovie
    from PyQt5.QtWidgets import QApplication, QSplashScreen, QWidget
except ImportError:
    from PySide2.QtCore import Qt
    from PySide2.QtGui import QMovie
    from PySide2.QtWidgets import QApplication, QSplashScreen, QWidget


class GifSplashScreen(QSplashScreen):

    def __init__(self, *args, **kwargs):
        super(GifSplashScreen, self).__init__(*args, **kwargs)
        self.movie = QMovie('Data/splash.gif')
        self.movie.frameChanged.connect(self.onFrameChanged)
        self.movie.start()

    def onFrameChanged(self, _):
        self.setPixmap(self.movie.currentPixmap())

    def finish(self, widget):
        self.movie.stop()
        super(GifSplashScreen, self).finish(widget)


class BusyWindow(QWidget):

    def __init__(self, *args, **kwargs):
        super(BusyWindow, self).__init__(*args, **kwargs)
        # 模拟耗时操作，一般来说耗时的加载数据应该放到线程
        for i in range(5):
            sleep(1)
            splash.showMessage('加载进度: %d' % i, Qt.AlignHCenter | Qt.AlignBottom, Qt.white)
            QApplication.instance().processEvents()

        splash.showMessage('初始化完成', Qt.AlignHCenter | Qt.AlignBottom, Qt.white)
        splash.finish(self)


if __name__ == '__main__':
    import sys
    import cgitb

    cgitb.enable(format='text')

    app = QApplication(sys.argv)

    global splash
    splash = GifSplashScreen()
    splash.show()

    w = BusyWindow()
    w.show()

    # 测试二
    # def createWindow():
    #     app.w = QWidget()
    #     # 模拟初始5秒后再显示
    #     splash.showMessage('等待界面显示', Qt.AlignHCenter | Qt.AlignBottom, Qt.white)
    #     QTimer.singleShot(3000, lambda: (
    #         splash.showMessage('初始化完成', Qt.AlignHCenter | Qt.AlignBottom, Qt.white), app.w.show(),
    #         splash.finish(app.w)))

    # 模拟耗时5秒。但是不能用sleep
    # 可以使用子线程加载耗时的数据
    # 主线程中循环设置UI可以配合QApplication.instance().processEvents()
    # QTimer.singleShot(3000, createWindow)

    splash.showMessage('等待创建界面', Qt.AlignHCenter | Qt.AlignBottom, Qt.white)

    sys.exit(app.exec_())