[Python] Add widgets to MDTabsCarousel dynamically in KivyMD

Taking inspiration from the MDTabsCarousel example, I am trying to add tabs and content to the MDTabsPrimary and MDTabsCarousel at the runtime (KivyMD 2.0.1.dev0). More precisely, I am passing the data from one MDScreen to the other (containing the MDTabsPrimary) at the on_press() of a button. The problem is that the example uses the MDApp.on_start() method for doing these, whereas I am trying to do the same inside the MDScreen.on_enter(). This causes the following error:

Traceback (most recent call last):
File "C:\Users\sapta\miniconda3\envs\android\lib\site-packages\kivy\app.py", line 956, in run
runTouchApp()
File "C:\Users\sapta\miniconda3\envs\android\lib\site-packages\kivy\base.py", line 574, in runTouchApp
EventLoop.mainloop()
File "C:\Users\sapta\miniconda3\envs\android\lib\site-packages\kivy\base.py", line 339, in mainloop
self.idle()
File "C:\Users\sapta\miniconda3\envs\android\lib\site-packages\kivy\base.py", line 379, in idle
Clock.tick()
File "C:\Users\sapta\miniconda3\envs\android\lib\site-packages\kivy\clock.py", line 733, in tick
self.post_idle(ts, self.idle())
File "C:\Users\sapta\miniconda3\envs\android\lib\site-packages\kivy\clock.py", line 776, in post_idle
self._process_events()
File "kivy\\_clock.pyx", line 620, in kivy._clock.CyClockBase._process_events
File "kivy\\_clock.pyx", line 653, in kivy._clock.CyClockBase._process_events
File "kivy\\_clock.pyx", line 649, in kivy._clock.CyClockBase._process_events
File "kivy\\_clock.pyx", line 218, in kivy._clock.ClockEvent.tick
File "C:\Users\sapta\miniconda3\envs\android\lib\site-packages\kivymd\uix\tab\tab.py", line 1234, in <lambda>
lambda x: self._tabs_carousel.current_slide.tab_item.dispatch(
AttributeError: 'NoneType' object has no attribute 'tab_item'


Minimal (non-)working example:

from kivy.lang import Builder
from kivymd.app import MDApp
from kivymd.uix.list import (
MDListItem, MDListItemHeadlineText, MDListItemLeadingIcon
)
from kivymd.uix.screen import MDScreen
from kivymd.uix.screenmanager import MDScreenManager
from kivymd.uix.tab import MDTabsItem, MDTabsItemIcon, MDTabsItemText


KV = '''
<MyScreen1>:
MDButton:
style: "elevated"
pos_hint: {"center_x": .5, "center_y": .5}
on_press: root.on_press(*args)
MDButtonIcon:
icon: "plus"
MDButtonText:
text: "Elevated"

<MyScreen2>:
md_bg_color: self.theme_cls.backgroundColor

MDTabsPrimary:
id: tabs
pos_hint: {"center_x": .5, "center_y": .5}
size_hint_x: 0.8
allow_stretch: False

MDDivider:

MDTabsCarousel:
id: related_content_container
size_hint_y: None
height: dp(320)
'''

class MyScreen2(MDScreen):
def on_enter(self, *args):
for item in self.my_data:
self.ids.tabs.add_widget(
MDTabsItem(
MDTabsItemIcon(
icon="airplane",
),
MDTabsItemText(
text=item,
),
)
)
self.ids.related_content_container.add_widget(
MDListItem(
MDListItemLeadingIcon(icon="email"),
MDListItemHeadlineText(text=item),
)
)


class MyScreen1(MDScreen):
def on_press(self, *args):
self.manager.get_screen("screen_2").my_data = ["item_1", "item_2", "item_3"]
self.manager.current = "screen_2"


class Example(MDApp):
def build(self):
self.theme_cls.primary_palette = "Olive"
_ = Builder.load_string(KV)

self.sm = MDScreenManager()
self.sm.add_widget(
MyScreen1(
name="screen_1",
md_bg_color=self.theme_cls.backgroundColor,
)
)
self.sm.add_widget(
MyScreen2(
name="screen_2",
md_bg_color=self.theme_cls.backgroundColor,
)
)

return self.sm


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

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