Android app pause and resume

[Degenerate Tech]

I have made a simple paint app for Android ..after resume my paint app all drawing being lost....I want to save drawing instructions in a file during pause and I want to draw previous drawing during resume mode..how to do that ?

[planckp...@gmail.com]

Two separate things.

1) You can save stuff on_pause() [ see any Python tutorial for writing files], but you don't need to.

p4a will automatically save/resume any class variable (self.whatever) state.

2) Either

a) Save the information used to create the drawing instruction in a class variable. So for example when you define a new_line used by a Line() canvas instruction add it to a save list self.lines.append(new_line). Then create the canvas instruction from the saved data. Obviously there is other data to save, you are probably going to create a list of dict.

b) Consider using InstructionGroup to create a set of instruction and gave the group in  class variable.

https://kivy.org/doc/stable/api-kivy.graphics.instructions.html#kivy.graphics.instructions.InstructionGroup

I don't have an example.