Question

此代码根据选择的按钮运行25分钟，5分钟或10分钟倒数计时器。如何使运行计时器暂停，恢复和重置？我需要帮助为这三个功能编写回调。它们将链接到窗口顶部的三个按钮。这是我的代码：

from tkinter import *

class Application(Frame):
    def __init__(self,master):
        super(Application,self).__init__(master)
        self.pack()
        self.createWidgets()
        self._alarm_id = None

    def createWidgets(self):
        self.someFrame = Frame(self)
        self.startButton = Button(self.someFrame, text="Start",command=self.startTime)
        self.startButton.pack(side=LEFT)

        self.stopButton = Button(self.someFrame, text="Stop", command=self.stopTime)
        self.stopButton.pack(side=LEFT)

        self.resetButton = Button(self.someFrame, text="Reset", command=self.resetTime)
        self.resetButton.pack(side=LEFT)
        self.someFrame.pack(side=TOP)

        self.labelvariable = StringVar()
        self.labelvariable.set("25:00")

        self.thelabel = Label(self,textvariable = self.labelvariable,font=('Helvetica',50))
        self.thelabel.pack(side=TOP)

        self.firstButton = Button(self,text="pomodoro",command=self.pomodoro)
        self.firstButton.pack(side=LEFT)

        self.secondButton = Button(self,text="short break",command=self.shortBreak)
        self.secondButton.pack(side=LEFT)

        self.thirdButton = Button(self,text="long break",command=self.longBreak)
        self.thirdButton.pack(side=LEFT)

    def pomodoro(self):
        if self._alarm_id is not None:
            self.master.after_cancel(self._alarm_id)
        self.countdown(1500)

    def shortBreak(self):
        if self._alarm_id is not None:
            self.master.after_cancel(self._alarm_id)
        self.countdown(300)

    def longBreak(self):
        if self._alarm_id is not None:
            self.master.after_cancel(self._alarm_id)
        self.countdown(600)


    def startTime(self):
        pass

    def stopTime(self):
        pass

    def resetTime(self):
        pass

    def countdown(self, timeInSeconds):
        mins,secs = divmod(timeInSeconds, 60)
        timeformat = "{0:02d}:{1:02d}".format(mins, secs)
        app.labelvariable.set(timeformat)
        self._alarm_id = self.master.after(1000, self.countdown, timeInSeconds-1)


if __name__ == '__main__':
    root = Tk()
    root.title("Timer")
    app = Application(root)
    root.mainloop()

Answer 1

当你点击三个按钮中的每个按钮时，你的问题仍然有点模糊，所以我不得不猜测。为了支持执行这些操作的能力，需要添加几个实例属性来跟踪应用程序的状态 - 即self._paused和self._starttime。可以根据需要以各种方法检查和更新这些内容。

from tkinter import *

class Application(Frame):
    def __init__(self,master):
        super(Application,self).__init__(master)
        self.pack()
        self.createWidgets()
        self._alarm_id = None
        self._paused = False
        self._starttime = 25 * 60

    def createWidgets(self):
        self.someFrame = Frame(self)
        self.startButton = Button(self.someFrame, text="Start",command=self.startTime)
        self.startButton.pack(side=LEFT)

        self.stopButton = Button(self.someFrame, text="Stop", command=self.stopTime)
        self.stopButton.pack(side=LEFT)

        self.resetButton = Button(self.someFrame, text="Reset", command=self.resetTime)
        self.resetButton.pack(side=LEFT)
        self.someFrame.pack(side=TOP)

        self.labelvariable = StringVar()
        self.labelvariable.set("25:00")

        self.thelabel = Label(self,textvariable = self.labelvariable,font=('Helvetica',50))
        self.thelabel.pack(side=TOP)

        self.firstButton = Button(self,text="pomodoro",command=self.pomodoro)
        self.firstButton.pack(side=LEFT)

        self.secondButton = Button(self,text="short break",command=self.shortBreak)
        self.secondButton.pack(side=LEFT)

        self.thirdButton = Button(self,text="long break",command=self.longBreak)
        self.thirdButton.pack(side=LEFT)

    def pomodoro(self):
        if self._alarm_id is not None:
            self.master.after_cancel(self._alarm_id)
        self.countdown(1500)

    def shortBreak(self):
        if self._alarm_id is not None:
            self.master.after_cancel(self._alarm_id)
        self._paused = False
        self.countdown(300)

    def longBreak(self):
        if self._alarm_id is not None:
            self.master.after_cancel(self._alarm_id)
        self._paused = False
        self.countdown(600)

    def startTime(self):
        """ Resume """
        self._paused = False
        if self._alarm_id is None:
            self.countdown(self._starttime)

    def stopTime(self):
        """ Pause """
        if self._alarm_id is not None:
            self._paused = True

    def resetTime(self):
        """ Restore to last countdown value. """
        if self._alarm_id is not None:
            self.master.after_cancel(self._alarm_id)
            self._alarm_id = None
            self._paused = False
            self.countdown(self._starttime)
            self._paused = True

    def countdown(self, timeInSeconds, start=True):
        if start:
            self._starttime = timeInSeconds
        if self._paused:
            self._alarm_id = self.master.after(1000, self.countdown, timeInSeconds, False)
        else:
            mins, secs = divmod(timeInSeconds, 60)
            timeformat = "{0:02d}:{1:02d}".format(mins, secs)
            app.labelvariable.set(timeformat)
            self._alarm_id = self.master.after(1000, self.countdown, timeInSeconds-1, False)


if __name__ == '__main__':
    root = Tk()
    root.title("Timer")
    app = Application(root)
    root.mainloop()

如何在tkinter倒数计时器上实现启动，停止和重置功能？

1 个答案: