如何使用 Kivy 使復選框啟用/禁用按鈕？

Question

如果選中該復選框，我希望啟用該按鈕。 如果未選中，我希望將其禁用。 我認為這就是我的disable_button function 通過檢查復選框是否被選中if self.ids.checkbox_confirm.active == False:然后禁用按鈕self.ids.submit_button.disabled == True的。 但是，后一種說法沒有做任何事情。

主程序

from kivy.app import App
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.core.window import Window
from kivy.properties import ObjectProperty


class MainWindow(Screen):
    def on_pre_enter(self):
        Window.size=(750,400)

    def checkbox_click(self, instance, value):
        return value

    def disable_button(self):
        print(self.ids.checkbox_confirm.active)
        if self.ids.checkbox_confirm.active == False:
            self.ids.submit_button.disabled == True
        else:
            self.ids.submit_button.disabled == False


class SecondWindow(Screen):
    def on_pre_enter(self):
        Window.fullscreen='auto'
    pass

class WindowManager(ScreenManager):
    pass

class MyMainApp(App):
    def build(self):
        Window.clearcolor = (1,1,1,1)
        return kv

kv = Builder.load_file("my.kv")

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

.kv 文件

WindowManager:
    MainWindow:
    SecondWindow:

<MainWindow>:
    name: "main"

    BoxLayout:
        orientation: "vertical"
        size: root.width, root.height
        padding: 50

        Label:
            text: "Email"
            color: 0,0,0,1
            font_size: 32

        BoxLayout:
            orientation: "horizontal"
            Label:
                text: "Email Address:"
                color: 0,0,0,1

            TextInput:
                size_hint_y: None
                pos_hint: {'center_y': .5}
                height: 38
                multiline: True
                padding: 10
        BoxLayout:
            orientation: "horizontal"

            Label:
                text: "I double-checked that my email is typed correctly:"
                color: 0,0,0,1
            CheckBox:
                id: checkbox_confirm
                on_active:
                    root.checkbox_click(self, self.active)
                    root.disable_button()
                pos_hint: {'center_x': .5}


        BoxLayout
            orientation: "vertical"

            Button:
                id:submit_button
                text: "Submit"

                size_hint: (0.2, None)
                pos_hint: {'center_x': .5}
                height: 50


                on_release:
                    app.root.current = "second"
                    root.manager.transition.direction = "left"

<SecondWindow>:
    name: "second"

Answer 1

我沒有測試它，但你的代碼有錯字。

要分配新值，您必須使用=而不是==

if self.ids.checkbox_confirm.active == False:
    self.ids.submit_button.disabled = True   # need `=` instead of `==`
else:
    self.ids.submit_button.disabled = False  # need `=` instead of `==`

---

順便提一句：

您可以使用not在單行中編寫它

self.ids.submit_button.disabled = not self.ids.checkbox_confirm.active