如何获取文件名，并在标签中保存和显示这些名称。KivyMD基维巨蟒

from kivy.lang import Builder
from kivy.uix.boxlayout import BoxLayout
from kivymd.app import MDApp
from kivymd.uix.button import MDRectangleFlatButton
from kivymd.uix.label import MDLabel
from kivy.uix.filechooser import FileChooserListView

KV = '''
<MainLayout>:
    orientation: 'vertical'
    MDRectangleFlatButton:
        text: 'Select File'
        pos_hint: {'center_x': 0.5, 'center_y': 0.7}
        on_release: file_chooser.open()
    MDLabel:
        id: file_label
        text: 'No file selected'
        halign: 'center'
        font_style: 'H5'
        size_hint_y: None
        height: self.texture_size[1]

<FileChooserListView>:
    on_selection: app.update_label(self.selection)
'''

class MainLayout(BoxLayout):
    pass

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

    def update_label(self, selection):
        if selection:
            self.root.ids.file_label.text = selection[0]
        else:
            self.root.ids.file_label.text = 'No file selected'

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