Kivy 简单倒计时分秒计时器

Question

所以我想构建一个 kivy 程序，它基本上只是倒计时特定的分钟和秒。

这是我走了多远：

from kivy.app import App
from kivy.uix.label import Label
from kivy.clock import Clock

from datetime import datetime, date, time


class IncrediblyCrudeClock(Label):
    a = time(0, 1, 1)

    def update(self, *args):
        self.text = str(self.a)
        print(str(self.a))

        self.a = datetime.combine(date.today(), self.a) - datetime.combine(date.today(), time(0,0,1))

class TimeApp(App):
    def build(self):
        crudeclock = IncrediblyCrudeClock()
        Clock.schedule_interval(crudeclock.update, 1)
        return crudeclock

if __name__ == "__main__":
    TimeApp().run()

问题是，当我尝试从新时间中扣除旧时间时，显示的时间减少了 1 秒，出现以下错误：

self.a = datetime.combine(date.today(), self.a) datetime.combine(date.today(), time(0,0,1))
 TypeError: combine() argument 2 must be datetime.time, not datetime.timedelta

这让我觉得，在第一次 sustraction 之后， a 现在不再是“时间”对象，而是不幸无法扣除的“时间增量”。

任何帮助都会很棒！

Answer 1

如果您只需要倒计时，还有一种更简单的方法。您可以使用 kivy 的Animation课程，@inclement 在youtube 上对此进行了很好的描述。所以这是代码（main.py 和 time.kv）：

主文件

from kivy.app import App
from kivy.uix.label import Label
from kivy.animation import Animation
from kivy.properties import StringProperty, NumericProperty


class IncrediblyCrudeClock(Label):
    a = NumericProperty(5)  # seconds

    def start(self):
        Animation.cancel_all(self)  # stop any current animations
        self.anim = Animation(a=0, duration=self.a)
        def finish_callback(animation, incr_crude_clock):
            incr_crude_clock.text = "FINISHED"
        self.anim.bind(on_complete=finish_callback)
        self.anim.start(self)

class TimeApp(App):
    def build(self):
        crudeclock = IncrediblyCrudeClock()
        crudeclock.start()
        return crudeclock

if __name__ == "__main__":
    TimeApp().run()

时间.kv

<IncrediblyCrudeClock>
    text: str(round(self.a, 1))

享受！:)

更新：

OP 要求一个没有 kv 文件的解决方案——所以这里是一个：

from kivy.app import App
from kivy.uix.label import Label
from kivy.animation import Animation
from kivy.properties import StringProperty, NumericProperty


class IncrediblyCrudeClock(Label):
    a = NumericProperty(5)  # seconds

    def start(self):
        Animation.cancel_all(self)  # stop any current animations
        self.anim = Animation(a=0, duration=self.a)
        def finish_callback(animation, incr_crude_clock):
            incr_crude_clock.text = "FINISHED"
        self.anim.bind(on_complete=finish_callback)
        self.anim.start(self)

    def on_a(self, instance, value):
        self.text = str(round(value, 1))

class TimeApp(App):
    def build(self):
        crudeclock = IncrediblyCrudeClock()
        crudeclock.start()
        return crudeclock

if __name__ == "__main__":
    TimeApp().run()