如何使用 PyQt5 for Python 显示计时器

Question

我正在制作一款游戏，我希望在用户点击“新游戏”后在屏幕上显示一个计时器，以跟踪他们玩了多长时间。 我有一个单独运行计时器的类，但是当我将它合并到我的游戏的其余部分然后最重要的是，尝试显示计时器的更新值时，UI 中的任何值都不会更新并且打印输出计时器甚至不会出现在终端中。 我试过在与游戏设置过程相同的线程中运行计时器，我也尝试过创建一个新线程来运行计时器，但都不起作用。 游戏加载并运行正常，除了计时器不向上计数并且不显示更新的计时器值。 我哪里错了？

这是我的独立 Timer 类，它本身也能正常工作。

from PyQt5 import QtCore
import sys

def startThread(functionName, *args, **kwargs):
    print(args)
    if len(args) == 0:
        t = threading.Thread(target=functionName)
    else:
        try:
            t = threading.Thread(target=functionName, args=args, kwargs=kwargs)
        except:
            try:
                if args is None:
                    t = threading.Thread(target=functionName, kwargs=kwargs)
            except:
                t = threading.Thread(target=functionName)
    t.daemon = True
    t.start()

class Timer(object):

    def __init__(self):
        super(Timer, self).__init__()

    def start_timer(self):
        print("Starting timer...")
        Timer.timer = QtCore.QTimer()
        Timer.time = QtCore.QTime(0, 0, 0)
        Timer.timer.timeout.connect(self.tick)
        Timer.timer.start(1000)

    def tick(self):
        Timer.time = Timer.time.addSecs(1)
        self.update_UI('%s' % Timer.time.toString("hh:mm:ss"))

    def update_UI(self, text_string):
        print(text_string)
        # This is where the text would be sent to try and update the UI

Timer().start_timer()

这或多或少是我的游戏设置类的结构——目前我展示的是使用线程的版本：

class BuildUI(PyQt5.QtWidgets.QMainWindow, Ui_game):

    def __init__(self):
        super(BuildUI, self).__init__()
        self.setupUi(self)
        self.easy_mode = 38
        self.user_available_cells = []
        self.start_easy_game.triggered.connect(lambda: self.setup_game(self.easy_mode))

    def setup_game(self, hidden_count):
        def create_game_board():
            startThread(Timer().start_timer)
            self.game = BuildGame()
                    #The BuildGame class is not deliberately not shown

        startThread(create_game_board)

class GAME(object):
    def __init__(self):
        GAME.app = PyQt5.QtWidgets.QApplication(sys.argv)
        GAME.UI = BuildUI()
        GAME.UI.show()
        GAME.app.exec_()

def main():
    GAME()

if __name__ == '__main__':
    main()

Answer 1

让它工作的关键是使用信号。 完全保留Timer类，唯一要做的修改是在GAME类的初始化中，需要在 BuildUI 类的开头添加一个信号，然后使用 emit() 在self.game = BuildGame()调用。

class BuildUI(PyQt5.QtWidgets.QMainWindow, sudoku_ui.Ui_sudoku_game):
    # This signal just triggers a msgbox to display, telling the user the game is loading
    process_start = PyQt5.QtCore.pyqtSignal()
    # this is called to automatically close the msgbox window       
    process_finished = PyQt5.QtCore.pyqtSignal()
    # This signal, when called will start the timer
    start_game_timer = PyQt5.QtCore.pyqtSignal()

    def __init__(self):
        super(BuildUI, self).__init__()
        self.setupUi(self)
        self.easy_mode = 38
        self.user_available_cells = []
        self.start_easy_game.triggered.connect(lambda: self.setup_game(self.easy_mode))

    def setup_game(self, hidden_count):
        def create_game_board():
            self.game = BuildGame()
            # Now that the game is built, the timer can start
            # This is the emit which will start the timer
            GAME.UI.start_game_timer.emit()

        startThread(create_game_board)

class GAME(object):
    def __init__(self):
        GAME.app = PyQt5.QtWidgets.QApplication(sys.argv)
        GAME.UI = BuildUI()
        GAME.dialog_box = MsgPrompt()

        # This is the key right here - initializing the timer class
        GAME.timer = Timer()
        # This line below attaches a function to the emit() call - which will kick off the timer
        GAME.UI.start_game_timer.connect(GAME.timer.start_timer)
        # The below referenced class is deliberately omitted from this post
        GAME.UI.process_start.connect(GAME.dialog_box.show_dialog_box)
        GAME.UI.process_finished.connect(GAME.dialog_box.hide_dialog_box)
        GAME.UI.show()
        GAME.app.exec_()

def main():
    GAME()

if __name__ == '__main__':
    main()