如何在FloatLayout中移动循环进度条和它的进度数字？

from kivy.app import App
from kivy.uix.floatlayout import FloatLayout
from kivy.uix.progressbar import ProgressBar
from kivy.uix.label import Label

class MyFloatLayout(FloatLayout):
    def __init__(self, **kwargs):
        super(MyFloatLayout, self).__init__(**kwargs)
        
        # 创建循环进度条
        self.progress_bar = ProgressBar(max=100, value=50)
        self.add_widget(self.progress_bar)
        
        # 创建进度数字
        self.progress_label = Label(text=str(int(self.progress_bar.value)) + "%")
        self.add_widget(self.progress_label)
        
    def on_touch_move(self, touch):
        if self.progress_bar.collide_point(*touch.pos):
            # 更新循环进度条位置
            self.progress_bar.pos = touch.pos
            
            # 更新进度数字位置
            self.progress_label.pos = (touch.pos[0], touch.pos[1] - 30)
            
class MyApp(App):
    def build(self):
        return MyFloatLayout()

if __name__ == '__main__':
    MyApp().run()