Kivy：使用按钮更新 TextInput 元素

Question

I recently started making a Kivy App.

What it should do so far is change the TextInput element from "Password will appear here" to "Cleared." when the user presses the "Clear" button.

Unfortunately nothing happens and I am not sure why.

Code:

class Main(FloatLayout):

    def __init__(self, **kwargs):
        super(Main, self).__init__(**kwargs)
        self.cols = 2
        self.rows = 3
        self.add_widget(Label(text=str("Random Password Generator"), size_hint_y=None, pos=(20,600), color=(1, 204/255, 102/255)))
        self.checkBox1 = CheckBox(active=False)
        self.add_widget(self.checkBox1)
        self.dropdown = DropDown()
        for index in range(50):
            btn = Button(text='%d' % index, pos_hint=(200,200), size_hint_y=None, height=44)
            btn.bind(on_release=lambda btn: self.dropdown.select(btn.text))
            self.dropdown.add_widget(btn)
        self.mainbutton = Button(text='Char Count', size_hint=(0.08, 0.05), pos=(427,400))
        self.mainbutton.bind(on_release=self.dropdown.open)
        self.add_widget(self.mainbutton)
        self.dropdown.bind(on_select=lambda instance, x: setattr(self.mainbutton, 'text', "Char Count: " + x))
        self.textBox = TextInput(text="Password will appear here", size_hint=(0.4, 0.05), pos=(427, 520))
        self.add_widget(self.textBox)
        self.clearButton = Button(text="Clear", size_hint=(0.08,0.05), pos=(427,440))
        self.clearButton.bind(on_select=self.clearBox)
        self.add_widget(self.clearButton)
    def clearBox(self):
        self.textBox.text = "Cleared!"
class KeycardApp(App):

    def build(self):
        return Main()

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

Feel free to laugh if I am being stupid...

Answer 1

Fixed by doing this:

self.clearButton.bind(on_release=lambda a: self.clearBox())

Changing to on_release gave me the error code "takes 0 positional arguments, but 1 was given" so I added lambda a: to reroute the argument to nothing... and it worked!!!