KIVY : 滚动条丢失

Question

我正在尝试在anchorlayout中使用ScrollView。无法在Relativelayout中获得滚动条。请看下面的示例代码。为什么滚动条不可见。

import kivy
from kivy.app import App
from kivy.uix.scrollview import ScrollView
from kivy.lang import Builder
from kivy.uix.relativelayout import RelativeLayout
from kivy.uix.button import Button
from kivy.factory import Factory
from kivy.core.window import Window

Builder.load_string('''
<ScrollView>:
    size_hint: 1,1
    DrawingSpace:
        size_hint: 1,1
''')

class Main(App):
    def build(self):
        self.root=DrawingSpace()
        return self.root

class DrawingSpace(RelativeLayout):
    def __init__(self, **kwargs):
        super(RelativeLayout, self).__init__(**kwargs)
        self.add_widget( Button(text = 'Scroll', size_hint=(None,None), size=(50,200), pos = (100, 100)))
        self.add_widget( Button(text = 'Scroll', size_hint=(None,None), size=(50,200), pos = (250, 300)))

Factory.register('DrawingSpace', cls=DrawingSpace)

if __name__ in ('__main__'):
    Window.size = (200, 200)
    app = Main()
    app.run()

谢谢。

Answer 1

对于 ScrollView在你想要滚动的方向上，你必须设置为 size_hint 到 None 并指定大小。我用500来测试。

import kivy
from kivy.app import App
from kivy.uix.scrollview import ScrollView
from kivy.lang import Builder
from kivy.uix.relativelayout import RelativeLayout
from kivy.uix.button import Button
from kivy.factory import Factory
from kivy.core.window import Window

Builder.load_string('''
<ScrollView>:
    size_hint: 1,1
    DrawingSpace:
        size_hint: 1,None
        height: 500
''')

class Main(App):
    def build(self):
        self.root=ScrollView()
        return self.root

class DrawingSpace(RelativeLayout):
    def __init__(self, **kwargs):
        super(RelativeLayout, self).__init__(**kwargs)
        self.add_widget( Button(text = 'Scroll', size_hint=(None,None), size=(50,200), pos = (100, 100)))
        self.add_widget( Button(text = 'Scroll', size_hint=(None,None), size=(50,200), pos = (250, 300)))

Factory.register('DrawingSpace', cls=DrawingSpace)

if __name__ in ('__main__'):
    Window.size = (200, 200)
    app = Main()
    app.run()