Question

我有一个名为Tiles的全局变量，并希望将TreasureHuntGrid类中的cols数设置为kivy文件。

Main.py

Tiles = 5
class TreasureHuntGrid(GridLayout):
    global Tiles

.kv

<TreasureHuntGrid>:
cols: #Don't know what should I put in here

Answer 1

Globals are evil。如果您希望从任何窗口小部件访问变量，最好将其放入Application类，因为您的程序中只有一个实例：

from kivy.app import App
from kivy.uix.gridlayout import GridLayout
from kivy.lang import Builder

Builder.load_string("""
<MyWidget>:
    cols: app.tiles
    Label:
        text: "test"
    Label:
        text: "test"
    Label:
        text: "test"
    Label:
        text: "test"
    Label:
        text: "test"
    Label:
        text: "test"
    Label:
        text: "test"
    Label:
        text: "test"
    Label:
        text: "test"
""")

class MyWidget(GridLayout):
    pass

class MyApp(App):
    tiles = 5
    def build(self):
        return MyWidget()

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

话虽如此，如果您真的需要，可以访问这样的全局变量：

from kivy.app import App
from kivy.uix.gridlayout import GridLayout
from kivy.lang import Builder

tiles = 5

Builder.load_string("""
#: import tiles __main__.tiles

<MyWidget>:
    cols: tiles
    Label:
        text: "test"
    Label:
        text: "test"
    Label:
        text: "test"
    Label:
        text: "test"
    Label:
        text: "test"
    Label:
        text: "test"
    Label:
        text: "test"
    Label:
        text: "test"
    Label:
        text: "test"
""")

class MyWidget(GridLayout):
    pass

class MyApp(App):
    def build(self):
        return MyWidget()

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

如何在Kivy文件中访问全局变量？

1 个答案: