Python/Kivy Attribute Error

Question

I'm working on some code to create a UI for a touchscreen in Python/Kivy. I'm new to both, and am having a bit of trouble with it. I'm getting an AttributeError raised on return PtWidg(), but the console isn't giving me anything super helpful to work off of:

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

This is my python file, 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()

And here is the contents of my .kv file, 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

Really, any tips or tricks would help me out a lot. Thank you!

Answer 1

Your code has these errors:

1. You wrote sendButton instead of SendButton in kv file.
2. Also in kv file, you wrote db(50) instead of dp(50). Using string '50dp' would be also a valid option.