python kivy在矩形内添加文本

Question

如何在矩形内添加文本？我正在使用下面的代码，并在画布中添加了一个标签，希望它会显示在矩形内。

import kivy 
from kivy.app import App 
from kivy.uix.anchorlayout import AnchorLayout 
from kivy.uix.gridlayout import GridLayout 
from kivy.uix.label import Label 
from kivy.uix.video import Video 
from kivy.uix.relativelayout import RelativeLayout 
from kivy.graphics import * 

class MyApp(App): 
    def build(self): 
     r = AnchorLayout() 
     f = RelativeLayout() 
     g = GridLayout(cols=3, rows=5) 
     v = Video(source='driver.mp4', state='play', options={'eos':'loop'}) 
     l1 = Label(text="jenkins", font_size=32) 
     l2 = Label(text="git", font_size=32) 
     f.add_widget(v) 
     f.add_widget(g) 
     g.add_widget(l1) 
     g.add_widget(l2) 
     with g.canvas: 
      Color(.4, .1, .1) 
      Rectangle(pos=(100,10), size=(100,100)) 
      Label(text="KSHK") 
     return f 

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

更新： 在ColoredLabel

import kivy 
from kivy.app import App 
from kivy.uix.anchorlayout import AnchorLayout 
from kivy.uix.gridlayout import GridLayout 
from kivy.uix.label import Label 
from kivy.uix.video import Video 
from kivy.uix.relativelayout import RelativeLayout 
from kivy.graphics import * 
from kivy.lang import Builder 
from kivy.uix.boxlayout import BoxLayout 
from random import random 
from kivy.properties import ListProperty 


kv = ''' 
<ColoredLabel>: 
    background_color: 
    canvas.before: 
     Color: 
      rgba: self.background_color 
     Rectangle: 
      pos: (10,10) 
      size: (100,100) 
    ''' 

Builder.load_string(kv) 

class ColoredLabel(Label): 
    background_color = ListProperty((0,0,0,1)) 

class MyApp(App): 
    def build(self): 
     f = AnchorLayout() 
     g = GridLayout(cols=2, rows=2) 
     layout = BoxLayout(size_hint=(1, None), height=50) 
     v = Video(source='driver.mp4', state='play', options={'eos':'loop'}) 
     l1 = Label(text="jenkins", font_size=32) 
     l2 = Label(text="git", font_size=32) 
     f.add_widget(v) 


     label = ColoredLabel(text="Hello World!", background_color=(random(), random(), random(), 1)) 
     g.add_widget(label) 


     f.add_widget(g) 

     return f 

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

Answer 1

使用Label与自定义背景色的中心，这并不对齐文本，然后将其放到里面布局。例如：

from kivy.uix.label import Label 
from kivy.uix.boxlayout import BoxLayout 
from kivy.properties import ListProperty 
from kivy.app import App 
from kivy.lang import Builder 

from random import random 

kv = ''' 
<ColoredLabel>: 
    background_color: 
    canvas.before: 
     Color: 
      rgba: self.background_color 
     Rectangle: 
      pos: self.pos 
      size: self.size 
''' 

Builder.load_string(kv) 

class ColoredLabel(Label): 
    background_color = ListProperty((0, 0, 0, 1)) 

class TestApp(App): 
    def build(self): 
     layout = BoxLayout(size_hint=(1, None), height=50) 
     for label in ('a', 'b', 'c', 'd'): 
      label = ColoredLabel(text=label, background_color=(random(), random(), random(), 1)) 
      layout.add_widget(label) 

     return layout 

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

更新

从OP修复问题：

import kivy 
from kivy.app import App 
from kivy.uix.anchorlayout import AnchorLayout 
from kivy.uix.gridlayout import GridLayout 
from kivy.uix.label import Label 
from kivy.uix.video import Video 
from kivy.uix.relativelayout import RelativeLayout 
from kivy.graphics import * 
from kivy.lang import Builder 
from kivy.uix.boxlayout import BoxLayout 
from random import random 
from kivy.properties import ListProperty 


kv = ''' 
<ColoredLabel>: 
    size: (100,100) 
    pos: (10,10) # no effect 
    background_color: 
    canvas.before: 
     Color: 
      rgba: self.background_color 
     Rectangle: 
      pos: self.pos 
      size: self.size 
    ''' 

Builder.load_string(kv) 

class ColoredLabel(Label): 
    background_color = ListProperty((0,0,0,1)) 

class MyApp(App): 
    def build(self): 
     f = AnchorLayout() 
     g = GridLayout(cols=2, rows=2) 
     layout = BoxLayout(size_hint=(1, None), height=50) 
#  v = Video(source='driver.mp4', state='play', options={'eos':'loop'}) 
     l1 = Label(text="jenkins", font_size=32) 
     l2 = Label(text="git", font_size=32) 
#  f.add_widget(v) 

     label = ColoredLabel(text="Hello World!", size_hint=(None, None), background_color=(random(), random(), random(), 1)) 
     g.add_widget(label) 

     f.add_widget(g) 

     return f 

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

注意ColoredLabel的Rectange需要有pos: self.pos和size: self.size到位绘制在标签实际上是。这就是为什么我在上面的级别更改标签本身的大小。画布尺寸绑定到它。至于位置，它由放置ColoredLabel的布局控制，因此将其从ColoredLabel类更改为不会有太大变化。与FloatLayout比较：

import kivy 
from kivy.app import App 
from kivy.uix.anchorlayout import AnchorLayout 
from kivy.uix.gridlayout import GridLayout 
from kivy.uix.label import Label 
from kivy.uix.video import Video 
from kivy.uix.relativelayout import RelativeLayout 
from kivy.graphics import * 
from kivy.lang import Builder 
from kivy.uix.boxlayout import BoxLayout 
from random import random 
from kivy.properties import ListProperty 

from kivy.uix.floatlayout import FloatLayout 


kv = ''' 
<ColoredLabel>: 
    size: (150, 200) 
    pos: (50, 150) 
    background_color: 
    canvas.before: 
     Color: 
      rgba: self.background_color 
     Rectangle: 
      pos: self.pos 
      size: self.size 
    ''' 

Builder.load_string(kv) 

class ColoredLabel(Label): 
    background_color = ListProperty((0,0,0,1)) 

class MyApp(App): 
    def build(self): 
     f = FloatLayout() 
     label = ColoredLabel(text="Hello World!", size_hint=(None, None), background_color=(random(), random(), random(), 1)) 
     f.add_widget(label) 

     return f 

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

在这种情况下，改变ColoredLabel POS里面居然有效果。