Tabs showing an error ValueError: MDTabsLabel.color has an invalid format (got []) -Kivymd

Question

Actually I am getting an error when I am using tabs in kivymd. I tried using them as it is provided here . I am getting an error that follows:

 Traceback (most recent call last):
   File "kivy/properties.pyx", line 2023, in kivy.properties.ColorProperty.convert
   File "kivy/properties.pyx", line 2041, in kivy.properties.ColorProperty.parse_list
 ValueError: Invalid value for color (got [])
 
 The above exception was the direct cause of the following exception:
 
 Traceback (most recent call last):
   File "/home/ibn-e-wajid-al-medki/pythonProject/venv/lib/python3.8/site-packages/kivy/lang/builder.py", line 701, in _apply_rule
     setattr(widget_set, key, value)
   File "kivy/weakproxy.pyx", line 35, in kivy.weakproxy.WeakProxy.__setattr__
   File "kivy/properties.pyx", line 498, in kivy.properties.Property.__set__
   File "kivy/properties.pyx", line 527, in kivy.properties.Property.set
   File "kivy/properties.pyx", line 2025, in kivy.properties.ColorProperty.convert
 ValueError: MDTabsLabel.color has an invalid format (got [])
 
 During handling of the above exception, another exception occurred:
 
 Traceback (most recent call last):
   File "/home/ibn-e-wajid-al-medki/pythonProject/store.py", line 317, in <module>
     Example().run()
   File "/home/ibn-e-wajid-al-medki/pythonProject/venv/lib/python3.8/site-packages/kivy/app.py", line 949, in run
     self._run_prepare()
   File "/home/ibn-e-wajid-al-medki/pythonProject/venv/lib/python3.8/site-packages/kivy/app.py", line 944, in _run_prepare
     self.dispatch('on_start')
   File "kivy/_event.pyx", line 709, in kivy._event.EventDispatcher.dispatch
   File "/home/ibn-e-wajid-al-medki/pythonProject/store.py", line 300, in on_start
     self.root.ids.tabs.add_widget(Tab(text=name_tab))
   File "/home/ibn-e-wajid-al-medki/pythonProject/venv/lib/python3.8/site-packages/kivy/uix/floatlayout.py", line 65, in __init__
     super(FloatLayout, self).__init__(**kwargs)
   File "/home/ibn-e-wajid-al-medki/pythonProject/venv/lib/python3.8/site-packages/kivy/uix/layout.py", line 76, in __init__
     super(Layout, self).__init__(**kwargs)
   File "/home/ibn-e-wajid-al-medki/pythonProject/venv/lib/python3.8/site-packages/kivymd/uix/tab.py", line 374, in __init__
     self.tab_label = MDTabsLabel(tab=self)
   File "/home/ibn-e-wajid-al-medki/pythonProject/venv/lib/python3.8/site-packages/kivymd/uix/tab.py", line 328, in __init__
     super().__init__(**kwargs)
   File "/home/ibn-e-wajid-al-medki/pythonProject/venv/lib/python3.8/site-packages/kivy/uix/behaviors/togglebutton.py", line 84, in __init__
     super(ToggleButtonBehavior, self).__init__(**kwargs)
   File "/home/ibn-e-wajid-al-medki/pythonProject/venv/lib/python3.8/site-packages/kivy/uix/behaviors/button.py", line 121, in __init__
     super(ButtonBehavior, self).__init__(**kwargs)
   File "/home/ibn-e-wajid-al-medki/pythonProject/venv/lib/python3.8/site-packages/kivy/uix/label.py", line 318, in __init__
     super(Label, self).__init__(**kwargs)
   File "/home/ibn-e-wajid-al-medki/pythonProject/venv/lib/python3.8/site-packages/kivy/uix/widget.py", line 359, in __init__
     self.apply_class_lang_rules(
   File "/home/ibn-e-wajid-al-medki/pythonProject/venv/lib/python3.8/site-packages/kivy/uix/widget.py", line 463, in apply_class_lang_rules
     Builder.apply(
   File "/home/ibn-e-wajid-al-medki/pythonProject/venv/lib/python3.8/site-packages/kivy/lang/builder.py", line 541, in apply
     self._apply_rule(
   File "/home/ibn-e-wajid-al-medki/pythonProject/venv/lib/python3.8/site-packages/kivy/lang/builder.py", line 710, in _apply_rule
     raise BuilderException(rule.ctx, rule.line,
 kivy.lang.builder.BuilderException: Parser: File "<inline>", line 19:
 ...
      17:        )
      18:    color:
 >>   19:        self.text_color_active if self.state == 'down'         else self.text_color_normal
      20:    on_x: self._trigger_update_tab_indicator()
      21:    on_width: self._trigger_update_tab_indicator()
 ...
 ValueError: MDTabsLabel.color has an invalid format (got [])
   File "/home/ibn-e-wajid-al-medki/pythonProject/venv/lib/python3.8/site-packages/kivy/lang/builder.py", line 701, in _apply_rule
     setattr(widget_set, key, value)
   File "kivy/weakproxy.pyx", line 35, in kivy.weakproxy.WeakProxy.__setattr__
   File "kivy/properties.pyx", line 498, in kivy.properties.Property.__set__
   File "kivy/properties.pyx", line 527, in kivy.properties.Property.set
   File "kivy/properties.pyx", line 2025, in kivy.properties.ColorProperty.convert
 

Process finished with exit code 1

Though the code is same as it is provided there Example with tab Icon , I am getting this error. Any help is appereciated

I am using pycharm , ubuntu 20.04, and python 3.8 kivy 1.11.1 and kivymd 0.104.1. plz let me now if you need anything else.

Answer 1

I think this is fixed in the kivyMD repo, just not released yet.

You can install a newer version by referencing the repo directly. This version passes internal testing and fixes this issue for me. It also tried the tabs example you mention and that runs for me too.

pip install https://github.com/kivymd/KivyMD/archive/b70abb5.zip