KivyMD
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MDButton animation incomplete when changing screens.
Description of the Bug
When a button is used to switch screens, on returning to the first screen the button is seen as still elevated.
Seems to me like this is the expected behavior of Kivy (because the button is no longer visible it does not see the change in elevation event) but not of KivyMD.
It is possible this is an enhancement request. Since only the programmer knows the use of a button, the resolution may be to provide an api to allow the programmer to immediately reset the button elevation. A programmer might for example call this api on_release
. Simply setting button.elevation = 0
from on_release
does not have any effect.
In the example below, moving the cursor resets the elevation (presumably related to hover). This is not always the case, for example in tabs content, however this stickiness may be related to #1663 .
Code and Logs
from kivymd.app import MDApp
from kivy.lang import Builder
from kivymd.uix.screen import MDScreen
from kivymd.uix.screenmanager import MDScreenManager
Builder.load_string("""
<Screen1>:
md_bg_color: self.theme_cls.backgroundColor
MDBoxLayout:
orientation:'vertical'
MDLabel:
text: 'Press "Go to Screen 2" Button'
halign: "center"
MDButton:
on_release: root.manager.current = 'Two'
pos_hint: {"center_x": .5, "center_y": .5}
size_hint_y:0.5
MDButtonText
text: 'Go to Screen 2'
MDLabel:
<Screen2>:
md_bg_color: self.theme_cls.backgroundColor
MDBoxLayout:
orientation:'vertical'
MDLabel:
text: 'Press "Go to Screen 1" Button\\nThen look at the elevation of the Button in Screen 1\\nBEFORE moving the cursor,\\nTHEN move the cursor.'
halign: "center"
MDButton:
style: "elevated"
pos_hint: {"center_x": .5, "center_y": .5}
on_release: root.manager.current = 'One'
MDButtonText
text: 'Go to Screen 1'
MDLabel:
size_hint_y:0.2
""")
class Screen1(MDScreen):
pass
class Screen2(MDScreen):
pass
class TestApp(MDApp):
def build(self):
sm = MDScreenManager()
sm.add_widget(Screen1(name='One'))
sm.add_widget(Screen2(name='Two'))
return sm
TestApp().run()
Screenshots
Versions
- OS: Windows 11
- Python: 3.11.1
- Kivy: 2.3.0
- KivyMD: 2.0.1.dev0