circular_progressbar.py

from kivy.uix.label import Label
from kivy.lang import Builder
from kivy.properties import NumericProperty, ListProperty
from kivy.clock import Clock


Builder.load_string("""
<Circle>:
    canvas.before:
        Color:
            rgba: .5,.5,.5,.5
        Line:
            circle: [root.center_x, root.center_y, root.radius]
            width: root.thickness
            cap: "none"
        Color:
            hsv: [1*root.value/100*0.25,1,1]
        Line:
            circle: [root.center_x, root.center_y, root.radius, -0.8, (360 * root.value/100 + 0.8) ]
            width: root.thickness
            cap: "none"

    text: "{}%".format(root.value)
    font_size: "40sp"
""")


class Circle(Label):
    value = NumericProperty(0)
    radius = NumericProperty(100)
    thickness = NumericProperty(20)

    def __init__(self, **kwargs):
        super(Circle, self).__init__(**kwargs)
        self.pro_range = []
        self.event = Clock.schedule_interval(self.set,1/60)


    def set(self, dt):
        if len(self.pro_range):
            self.value = self.pro_range.pop(0)
        else:
            self.event.cancel()


    def set_value(self, value=0, *args):
        try:
            value = round(float(value),1)
        except:
            return False

        self.event.cancel()
        diff = value - self.value
        self.pro_range = []

        if abs(diff) > 0:
            for pro in range(int(self.value*10), int(value*10), int(diff) or 1):
                self.pro_range.append(pro/10)
            self.pro_range.append(value)

        self.event()



from kivy.app import App
from kivy.uix.floatlayout import FloatLayout
from kivy.uix.boxlayout import BoxLayout
from kivy.properties import ObjectProperty


class MyLayout(BoxLayout):
    circle = ObjectProperty(None)


KV = """

MyLayout:
    circle: circle
    TextInput:
        font_size: "30sp"
        text: "0"
        on_text:
            circle.set_value(self.text)
    Circle:
        id: circle
"""



class MyApp(App):

    def build(self):
        root = Builder.load_string(KV)
        return root


MyApp().run()