来自 ids 的 Kivy 回调自定义小部件调用引发 AttributeError

Question

我正在尝试从其 ID 调用自定义小部件方法。

但是我收到了 AttributeError: 'LabelBox' object has no attribute 'change_first_text'。

可以在 PanelApp.py 文件中找到尽可能简单的工作示例：

from kivy.app import App
from kivy.uix.tabbedpanel import TabbedPanel
from kivy.uix.boxlayout import BoxLayout
from kivy.lang import Builder

Builder.load_file("panel.kv")

class LabelBox(BoxLayout):
    def __init__(self, *args, **kwargs):
        super(LabelBox, self).__init__(*args, **kwargs)

    def change_first_text(self, text):
        self.ids.first.text = text

class ButtonList(BoxLayout):
    pass

class Test(TabbedPanel):
    pass


class TabbedPanelApp(App):
    def build(self):
        self.test = Test()
        self.btn_list = ButtonList()
        self.vbox = BoxLayout(orientation="vertical")
        self.vbox.add_widget(self.btn_list)
        self.vbox.add_widget(self.test)
        return self.vbox

    def change_first(self, value):
        print("Button clicked and new value is: '{}'".format(value))
        self.test.ids.lbs.change_first_text(value)


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

和 panel.kv 文件：

<ButtonList@ButtonList>:
    orientation: "horizontal"
    Button:
        text: "change fisrt to me"
        on_press: app.change_first(self.text)
    Button:
        text: "change two to me"

<LabelBox@BoxLayout>:
    Label:
        id: first
        text: "first"
    Label:
        id: two
        text: "two"

<Test>:
    size_hint: .5, .5
    pos_hint: {'center_x': .5, 'center_y': .5}
    do_default_tab: False

    TabbedPanelItem:
        text: 'first tab'
        LabelBox:
            id: lbs

调用脚本导致我无法理解的运行时错误。您知道如何通过应用程序管理此类事件回调吗？

Answer 1

你的问题是你正在创建 2 个 classes 叫做 LabelBox:

1.

class LabelBox(BoxLayout):
    def __init__(self, *args, **kwargs):
        super(LabelBox, self).__init__(*args, **kwargs)

    def change_first_text(self, text):
        self.ids.first.text = text

2.

<LabelBox@BoxLayout>:
    Label:
        id: first
        text: "first"
    Label:
        id: two
        text: "two"

我知道你只想有一个 class 所以在 .py 中创建继承是合适的，并且只在 [=14= 中实现 children ].解决方法是在.kv

中改delete @BoxLayout

<LabelBox>:
    Label:
        id: first
        text: "first"
    Label:
        id: two
        text: "two"

来自 ids 的 Kivy 回调自定义小部件调用引发 AttributeError

Kivy callback custom widget call from ids raise AttributeError

python

python-3.x

kivy

kivy-language