python - Kivy:如何在Python中引用kv ID？

Question

我是 Kivy 的新手，我不得不认为这是可能的，但我无法弄清楚 - 如何在按下按钮时更新 Kivy 标签，但只能通过在 Python 中引用 Kivy id ？ (我尝试这样做的原因是因为在我的实际应用程序中，我希望一次更新多个标签，我希望我可以在我的 button_pressed 等效按钮中完成所有操作我的应用程序中有)。

在下面的简单示例中，我只是尝试按下按钮，然后将标签更新为“已更新!”

非常感谢!

我的Python代码:

from kivy.app import App
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.widget import Widget
from kivy.properties import StringProperty
import random


class TestingWidget(BoxLayout):

    # This is the kv id of the Label I would like to update
    label_to_update = StringProperty('')

    # This is the action I would like to happen when the button is pressed
    def button_pressed(self):
        label_to_update.text = 'Updated!'

class TestButtonApp(App):
    def build(self):
        return TestingWidget()

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

我的 kv 文件:

<TestingWidget>:
    BoxLayout:
        orientation: 'horizontal'
        Button: 
            text: 'test'
            on_press: root.button_pressed()
        Label:
            id: label_to_update
            text: 'Trying to get this to update'

Answer 1

当您按下按钮时，您肯定会更新所有标签。只需为每个属性创建一个 StringProperty 并执行您现在正在执行的操作即可。

from kivy.app import App
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.widget import Widget
from kivy.properties import StringProperty
from kivy.lang import Builder #used because I didn't want to create two files

import random

Builder.load_string('''
<TestingWidget>:
    BoxLayout:
        orientation: 'horizontal'
        Button: 
            text: 'test'
            on_press: root.button_pressed()
        Label:
            id: label_to_update
            text: root.label_to_update 
            ''')
class TestingWidget(BoxLayout):

    # This is the kv id of the Label I would like to update
    label_to_update = StringProperty('Trying to get this to update')
    #default text set
    # This is the action I would like to happen when the button is pressed
    def button_pressed(self):
        self.label_to_update = 'Updated!'

class TestButtonApp(App):
    def build(self):
        return TestingWidget()

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