python - 更改 Kivy 小部件部分文本的颜色

Question

我正在尝试编写一个程序，如果按下按钮，标签小部件的部分文本的颜色就会发生变化。

例如，有一个带有文本“1/0”的 Label 小部件。现在，如果我按下按钮，1 的颜色就会变为某种指定的颜色。这是我尝试过的程序:

from kivy.app import App
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.button import Button
from kivy.lang import Builder
from kivy.utils import get_color_from_hex

Builder.load_string('''
#: import get_color_from_hex kivy.utils.get_color_from_hex
<b>:
    orientation: 'horizontal'
    Button:
        text: 'Press Me'
        on_press: num.text[0].color = get_color_from_hex('#04d3ff')

    Label:
        id: num
        text: '1/0'
''')

class b(BoxLayout):
    pass

class main(App):
    def build(self):
        return b()

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

这是我得到的错误:

Traceback (most recent call last):
   File "b.py", line 28, in <module>
     main().run()
   File "/usr/lib/python2.7/dist-packages/kivy/app.py", line 828, in run
     runTouchApp()
   File "/usr/lib/python2.7/dist-packages/kivy/base.py", line 487, in runTouchApp
     EventLoop.window.mainloop()
   File "/usr/lib/python2.7/dist-packages/kivy/core/window/window_sdl2.py", line 619, in mainloop
     self._mainloop()
   File "/usr/lib/python2.7/dist-packages/kivy/core/window/window_sdl2.py", line 362, in _mainloop
     EventLoop.idle()
   File "/usr/lib/python2.7/dist-packages/kivy/base.py", line 330, in idle
     self.dispatch_input()
   File "/usr/lib/python2.7/dist-packages/kivy/base.py", line 315, in dispatch_input
     post_dispatch_input(*pop(0))
   File "/usr/lib/python2.7/dist-packages/kivy/base.py", line 221, in post_dispatch_input
     listener.dispatch('on_motion', etype, me)
   File "kivy/_event.pyx", line 718, in kivy._event.EventDispatcher.dispatch (kivy/_event.c:7699)
   File "/usr/lib/python2.7/dist-packages/kivy/core/window/__init__.py", line 1030, in on_motion
     self.dispatch('on_touch_down', me)
   File "kivy/_event.pyx", line 718, in kivy._event.EventDispatcher.dispatch (kivy/_event.c:7699)
   File "/usr/lib/python2.7/dist-packages/kivy/core/window/__init__.py", line 1046, in on_touch_down
     if w.dispatch('on_touch_down', touch):
   File "kivy/_event.pyx", line 718, in kivy._event.EventDispatcher.dispatch (kivy/_event.c:7699)
   File "/usr/lib/python2.7/dist-packages/kivy/uix/widget.py", line 432, in on_touch_down
     if child.dispatch('on_touch_down', touch):
   File "kivy/_event.pyx", line 718, in kivy._event.EventDispatcher.dispatch (kivy/_event.c:7699)
   File "/usr/lib/python2.7/dist-packages/kivy/uix/behaviors/button.py", line 110, in on_touch_down
     self.dispatch('on_press')
   File "kivy/_event.pyx", line 714, in kivy._event.EventDispatcher.dispatch (kivy/_event.c:7654)
   File "kivy/_event.pyx", line 1224, in kivy._event.EventObservers.dispatch (kivy/_event.c:13497)
   File "kivy/_event.pyx", line 1108, in kivy._event.EventObservers._dispatch (kivy/_event.c:12329)
   File "/usr/lib/python2.7/dist-packages/kivy/lang.py", line 1557, in custom_callback
     exec(__kvlang__.co_value, idmap)
   File "<string>", line 7, in <module>
 AttributeError: 'str' object has no attribute 'color'

Answer 1

使用Kivy的基本markup syntax设置颜色以及标签中的 markup: True。