SDL2 caching event->DeviceId and event->source

[akshayaurora]

Credits https://hg.libsdl.org/SDL/rev/b5cd5e1e4440
Fixes kivy/kivy#6686, #1903, spesmilo/electrum#6276

Tested using the app provided in kivy/kivy#6686

from kivy.config import Config
Config.set('kivy', 'exit_on_escape', 'False')

from kivy.app import App
from kivy.lang import Builder
from kivy.core.window import Window
from kivy.uix.screenmanager import ScreenManager


Builder.load_string("""

<Main>:
    id: scr_mngr
    Screen:                           
        name: 'main'
        BoxLayout:
            orientation: "vertical"
            size_hint: 1,1
            pos_hint: {'top':1}
            Label:
                text: "Main Screen"
                size_hint: 1,.1
            Button:
                size_hint: 1,.1
                text: "Go Second Screen"
                on_press: root.go_second()
            Widget:
                
    Screen:                           
        name: 'second'
        BoxLayout:
            orientation: "vertical"
            size_hint: 1,1
            pos_hint: {'top':1}
            Label:
                text: "Second Screen"
                size_hint: 1,.1
            TextInput:
                size_hint: 1,.2
                text: "TextInput"
            Widget:
""")

class Main(ScreenManager):
    def __init__(self, **kwargs): 
        super(Main, self).__init__(**kwargs)
        Window.bind(on_keyboard = self.keyboard)
        
    def keyboard(self,window,key,*args):
        print(str(key))
        if key == 27:
            self.transition.direction  = "right"
            self.current = "main"
            
    def go_second(self,*args):
        self.transition.direction  = "left"
        self.current = "second"

class MyApp(App):    
    def build(self):
        return Main()

if __name__ == '__main__':
    MyApp().run()

[akshayaurora]

The successful tests I did were when using API=27.

On further examination, it seems the issue was not present when using android.api=27 the default. This issue is only present when using api=28 and this simple changes does not fix the issue when using android.api=28.

Closing

[SomberNight]

I have a new patch that works for me with API=28 for Electrum.
see SomberNight@c571db9
spesmilo/electrum#6276 (comment)

[akshayaurora]

@SomberNight nice job, would you please do a pr for p4a too.