問題描述

后續問題:Kivy 外部規則繼承

main.py

from kivy.app import App
from kivy.uix.button import Button
from kivy.uix.stacklayout import StackLayout
from kivy.properties import ObjectProperty
from kivy.factory import Factory


class FancyButton(Button):
    imp = ObjectProperty(None)


class Important(StackLayout):

    def NoInspiration(self, smile):
        print("Received: {}".format(smile))

    def AddFancy(self):
        temp = Factory.FancyButton(text='f', imp = self.ids.imp)
        self.ids.boxy.add_widget(temp)


class TestApp(App):
    def build(self):
        pass

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

test.kv

#:kivy 1.9.0
#:import App kivy.app

<FancyButton>:
    on_release: self.imp.NoInspiration(':)')


<Important>:
    id: imp

    BoxLayout:
        id: boxy
        orientation: 'vertical'

        FancyButton:
            text: "smiley"
            imp: root

        Button:
            text: "add fancy"
            on_release: imp.AddFancy()


BoxLayout:
    Important

在 test.kv 中，FancyButton 中對函數 NoInspiration() 的函數調用有效，因為 .kv 中定義的 FancyButton 具有 imp: root，所以它知道它應該在 < 中查找函數.重要>:.

In test.kv the function call in FancyButton to the function NoInspiration() works, because the FancyButton defined in the .kv has imp: root, so it knows it should look for the function in < Important >:.

但是當您在 Python 中通過 add_widget 創建 FancyButton 時 imp: root 是如何工作的?

However how does imp: root work when you create FancyButton through add_widget in Python?

現在當我按下添加花式"按鈕時，我得到了錯誤:

Now when I press the button "add fancy" I get the error:

文件main.py"，第 18 行，在 AddFancy 中temp = Factory.FancyButton(text='f', imp = self.ids.imp)文件properties.pyx"，第 756 行，在 kivy.properties.ObservableDict.__getattr __ (kivy/properties.c:11093)AttributeError: 'super' 對象沒有屬性 '__getattr __'

File "main.py", line 18, in AddFancy temp = Factory.FancyButton(text='f', imp = self.ids.imp) File "properties.pyx", line 756, in kivy.properties.ObservableDict.__getattr __ (kivy/properties.c:11093) AttributeError: 'super' object has no attribute '__getattr __'

跟進問題

Kivy 外部規則繼承 2

推薦答案

Widget.ids 僅包含其子項的 id (http://kivy.org/docs/api-kivy.uix.widget.html#kivy.uix.widget.Widget.ids. 不需要小部件本身的 ID，因為您可以直接傳遞它 - 在您的情況下使用 self，因為您從內部傳遞對小部件的引用一種方法:

Widget.ids only contain ids of its children (http://kivy.org/docs/api-kivy.uix.widget.html#kivy.uix.widget.Widget.ids. Id of the widget itself it's not needed because you can just pass it directly - in your case using self, since you're passing a reference to a widget from inside of a method:

class Important(StackLayout):
    def NoInspiration(self, smile):
        print("Received: {}".format(smile))

    def AddFancy(self):
        print(self.ids) # only returns {'boxy': <weakproxy at 0000000002D119A8 to BoxLayout at 0000000002D026A8>}
        self.ids.boxy.add_widget(FancyButton(text='f', imp = self)) # no need to use a factory

這篇關于使用 add_widget() 繼承 Kivy 規則的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網！