Enter this attribute in the manifest:
SetApplicationAttribute(android:theme, "@android:style/Theme.Translucent")
It will also have transverse activities.
Enter a main panel for each Activity so you can set
Activity.
Color =
Colors.
Tasparent
All activity views will be added to the Main Panel of each activity.
Then moving the panel remains only the transparent activity that will see the underlying activity. At the
end of the slide, raise the event stopped the activity (
Activity.Finish) and the underlying one will remain.
To scroll slide panel, see this example:
https://www.b4x.com/android/forum/threads/custombottomsheet-b4a-library-source-code.86121/
More than that I can not do for you.