Python/Kivy 属性错误

Question

我正在编写一些代码以在 Python/Kivy 中为触摸屏创建 UI。我对两者都是新手，并且遇到了一些麻烦。我在 return PtWidg() 时出现了一个 AttributeError，但控制台没有给我任何 super 有用的信息:

Traceback (most recent call last):
   File "/Users/revascharf/Documents/COLLEGE WORK/SENIOR YEAR/touchscreenInterface/touchUI.py", line 30, in <module>
     ptApp().run()
   File "/Applications/Kivy.app/Contents/Resources/kivy/kivy/app.py", line 802, in run
     root = self.build()
   File "/Users/revascharf/Documents/COLLEGE WORK/SENIOR YEAR/touchscreenInterface/touchUI.py", line 26, in build
     return PtWidg()
   File "/Applications/Kivy.app/Contents/Resources/kivy/kivy/uix/widget.py", line 320, in __init__
     Builder.apply(self, ignored_consts=self._kwargs_applied_init)
   File "/Applications/Kivy.app/Contents/Resources/kivy/kivy/lang.py", line 1970, in apply
     self._apply_rule(widget, rule, rule, ignored_consts=ignored_consts)
   File "/Applications/Kivy.app/Contents/Resources/kivy/kivy/lang.py", line 2044, in _apply_rule
     cls = Factory_get(cname)
   File "/Applications/Kivy.app/Contents/Resources/kivy/kivy/factory.py", line 130, in __getattr__
     raise AttributeError
 AttributeError

Process finished with exit code 1

这是我的 python 文件，touchUI.py:

import kivy
import datetime

from kivy.app import App
from kivy.uix.widget import Widget
from kivy.uix.button import Button

kivy.require('1.9.0')
from kivy.uix.image import Image


class SendButton(Button):
    def on_press(self):
        now = datetime.datetime.now()
        self.text = 'minute is ' + str(now.minute)


class PtWidg(Widget):
    pass


class ptApp(App):
    def build(self):
        return PtWidg()


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

这是我的 .kv 文件的内容，pt.kv:

#kivy 1.9.0

<sendButton>:
    size: 40, 30
    #pos: center_x + width / 4, center_y - height / 4


<PtWidg>:

    Image:
        center_x: root.width / 4
        top: root.top - 50
        source: 'SensoryWalkLogo.png'
        height: db(50)
        width: db(50)

    sendButton:
        center_x: root.width - root.width / 4
        top: root.top - 50
        text: 'Send minute to MSP430'
        font_size: 40

真的，任何提示或技巧都会对我有很大帮助。谢谢!

Answer 1

您的代码有这些错误:

1. 您在 kv 文件中编写了 sendButton 而不是 SendButton。
2. 同样在 kv 文件中，您编写了 db(50) 而不是 dp(50)。使用字符串 '50dp' 也是一个有效选项。