AttributeError: 'NoneType' object has no attribute 'dismiss'

[drscotthawley]

Auto-generated by kivy-designer itself, when trying "Run" after experiencing Issue #357 (that Issue refers to unending "[CRITICAL][Clock ]..." errors to the console immediately after creating project.)

To recreate:

1. Create New Project
2. Select Run > Run
3. Error occurs immediately

(I actually first experienced this when I selected "TabbedPanel" before clicking "Create New Project" -- I wanted to try to run the code to see the different tabs work, and it crashed with the same error. In doing some further checking, I came up with the three-step minimal example for this bug report.)

---

Environment Info

kivy: 1.10.1.dev0 pygments: 2.2.0 docutils: 0.14 watchdog: 0.8.3 jedi: 0.11.1 gitpython: 2.1.8 six: 1.11.0 kivy-garden: 0.1.4

Platform: Darwin-17.4.0-x86_64-i386-64bit Python: 3.5.3

Traceback

Traceback (most recent call last):
  File "/Users/shawley/anaconda/envs/py35/lib/python3.5/site-packages/kivy/core/window/window_sdl2.py", line 723, in mainloop
    self._mainloop()
  File "/Users/shawley/anaconda/envs/py35/lib/python3.5/site-packages/kivy/core/window/window_sdl2.py", line 460, in _mainloop
    EventLoop.idle()
  File "/Users/shawley/anaconda/envs/py35/lib/python3.5/site-packages/kivy/base.py", line 340, in idle
    self.dispatch_input()
  File "/Users/shawley/anaconda/envs/py35/lib/python3.5/site-packages/kivy/base.py", line 325, in dispatch_input
    post_dispatch_input(*pop(0))
  File "/Users/shawley/anaconda/envs/py35/lib/python3.5/site-packages/kivy/base.py", line 231, in post_dispatch_input
    listener.dispatch('on_motion', etype, me)
  File "kivy/_event.pyx", line 707, in kivy._event.EventDispatcher.dispatch
  File "/Users/shawley/anaconda/envs/py35/lib/python3.5/site-packages/kivy/core/window/__init__.py", line 1349, in on_motion
    self.dispatch('on_touch_up', me)
  File "kivy/_event.pyx", line 707, in kivy._event.EventDispatcher.dispatch
  File "/Users/shawley/anaconda/envs/py35/lib/python3.5/site-packages/kivy/core/window/__init__.py", line 1385, in on_touch_up
    if w.dispatch('on_touch_up', touch):
  File "kivy/_event.pyx", line 707, in kivy._event.EventDispatcher.dispatch
  File "/Users/shawley/anaconda/envs/py35/lib/python3.5/site-packages/kivy/uix/dropdown.py", line 310, in on_touch_up
    if super(DropDown, self).on_touch_up(touch):
  File "/Users/shawley/anaconda/envs/py35/lib/python3.5/site-packages/kivy/uix/scrollview.py", line 848, in on_touch_up
    if self.dispatch('on_scroll_stop', touch):
  File "kivy/_event.pyx", line 707, in kivy._event.EventDispatcher.dispatch
  File "/Users/shawley/anaconda/envs/py35/lib/python3.5/site-packages/kivy/uix/scrollview.py", line 887, in on_scroll_stop
    self.simulate_touch_down(touch)
  File "/Users/shawley/anaconda/envs/py35/lib/python3.5/site-packages/kivy/uix/scrollview.py", line 607, in simulate_touch_down
    ret = super(ScrollView, self).on_touch_down(touch)
  File "/Users/shawley/anaconda/envs/py35/lib/python3.5/site-packages/kivy/uix/widget.py", line 460, in on_touch_down
    if child.dispatch('on_touch_down', touch):
  File "kivy/_event.pyx", line 707, in kivy._event.EventDispatcher.dispatch
  File "/Users/shawley/anaconda/envs/py35/lib/python3.5/site-packages/kivy/uix/widget.py", line 460, in on_touch_down
    if child.dispatch('on_touch_down', touch):
  File "kivy/_event.pyx", line 707, in kivy._event.EventDispatcher.dispatch
  File "/Users/shawley/anaconda/envs/py35/lib/python3.5/site-packages/kivy/uix/behaviors/button.py", line 151, in on_touch_down
    self.dispatch('on_press')
  File "kivy/_event.pyx", line 707, in kivy._event.EventDispatcher.dispatch
  File "/Users/shawley/github/kivy-designer/designer/uix/action_items.py", line 183, in on_press
    self.cont_menu.dismiss()
AttributeError: 'NoneType' object has no attribute 'dismiss'

End of Traceback

[drscotthawley]

Noticed that the instructions say

Building To build, and run your project, you’ll need to configure the Kivy Designer Builder. The Builder will help you to target your application to the desired platforms. You can access Builder settings at Run -> Edit Profiles...

but when I do that (click on "Edit Profiles"), it crashes with the exact same error.

You guys are initializing cont_menu as cont_menu = ObjectProperty(None) on line 61 of kivy-designer/designer/uix/action_items.py.

...So I notice on line 158 you preface that call to dismiss() with an if self.cont_menu:.

Why does the earlier call check for None but the one on line 183 doesn't check?

...because adding that check before line 183 resolves this Issue.