use Chaquopy syntax directly in the android folder

android/setup.py

@@ -6,7 +6,6 @@
 setup(
     version=version,
     install_requires=[
-        "rubicon-java>=0.2.6",
         "toga-core==%s" % version,
     ],
 )

android/src/toga_android/app.py

@@ -1,21 +1,22 @@
 import asyncio
 
-from rubicon.java import android_events
+from java import dynamic_proxy
+from org.beeware.android import IPythonApp, MainActivity
 
 import toga
+from android.graphics.drawable import Drawable
 from android.media import RingtoneManager
+from android.view import Menu, MenuItem
 from toga.command import Group
 
-from .libs.activity import IPythonApp, MainActivity
-from .libs.android.graphics import Drawable
-from .libs.android.view import Menu, MenuItem
+from .libs import events
 from .window import Window
 
 # `MainWindow` is defined here in `app.py`, not `window.py`, to mollify the test suite.
 MainWindow = Window
 
 
-class TogaApp(IPythonApp):
+class TogaApp(dynamic_proxy(IPythonApp)):
     last_intent_requestcode = (
         -1
     )  # always increment before using it for invoking new Intents
@@ -170,7 +171,7 @@ def __init__(self, interface):
         self.interface._impl = self
         self._listener = None
 
-        self.loop = android_events.AndroidEventLoop()
+        self.loop = events.AndroidEventLoop()
 
     @property
     def native(self):

android/src/toga_android/colors.py

@@ -1,6 +1,6 @@
 from travertino.colors import NAMED_COLOR, TRANSPARENT
 
-from .libs.android.graphics import Color
+from android.graphics import Color
 
 CACHE = {TRANSPARENT: Color.TRANSPARENT}
 

android/src/toga_android/container.py

@@ -1,4 +1,5 @@
-from .libs.android.widget import RelativeLayout, RelativeLayout__LayoutParams
+from android.widget import RelativeLayout
+
 from .widgets.base import Scalable
 
 
@@ -56,7 +57,7 @@ def remove_content(self, widget):
         self.native_content.removeView(widget.native)
 
     def set_content_bounds(self, widget, x, y, width, height):
-        lp = RelativeLayout__LayoutParams(width, height)
+        lp = RelativeLayout.LayoutParams(width, height)
         lp.topMargin = y
         lp.leftMargin = x
         widget.native.setLayoutParams(lp)

android/src/toga_android/dialogs.py

@@ -1,11 +1,13 @@
 from abc import ABC
 
-from .libs.android import R__drawable
-from .libs.android.app import AlertDialog__Builder
-from .libs.android.content import DialogInterface__OnClickListener
+from java import dynamic_proxy
 
+from android import R
+from android.app import AlertDialog
+from android.content import DialogInterface
 
-class OnClickListener(DialogInterface__OnClickListener):
+
+class OnClickListener(dynamic_proxy(DialogInterface.OnClickListener)):
     def __init__(self, fn=None, value=None):
         super().__init__()
         self._fn = fn
@@ -44,7 +46,7 @@ def __init__(
         super().__init__(interface=interface)
         self.on_result = on_result
 
-        self.native = AlertDialog__Builder(interface.window._impl.app.native)
+        self.native = AlertDialog.Builder(interface.window._impl.app.native)
         self.native.setCancelable(False)
         self.native.setTitle(title)
         self.native.setMessage(message)
@@ -108,7 +110,7 @@ def __init__(self, interface, title, message, on_result=None):
             title=title,
             message=message,
             positive_text="OK",
-            icon=R__drawable.ic_dialog_alert,
+            icon=R.drawable.ic_dialog_alert,
             on_result=on_result,
         )
 

android/src/toga_android/fonts.py

@@ -1,5 +1,7 @@
 from pathlib import Path
 
+from android.graphics import Typeface
+from android.util import TypedValue
 from toga.fonts import (
     _REGISTERED_FONT_CACHE,
     BOLD,
@@ -15,8 +17,6 @@
     SYSTEM_DEFAULT_FONT_SIZE,
     SYSTEM_DEFAULT_FONTS,
 )
-from toga_android.libs.android.graphics import Typeface
-from toga_android.libs.android.util import TypedValue
 
 _FONT_CACHE = {}
 

android/src/toga_android/images.py

@@ -2,7 +2,7 @@
 
 from java.io import FileOutputStream
 
-from .libs.android.graphics import Bitmap, BitmapFactory
+from android.graphics import Bitmap, BitmapFactory
 
 
 class Image:

android/src/toga_android/keys.py

@@ -1,7 +1,6 @@
+from android.view import KeyEvent
 from toga.keys import Key
 
-from .libs.android.view import KeyEvent
-
 KEYEVENT_KEYS = {
     KeyEvent.KEYCODE_ESCAPE: Key.ESCAPE,
     KeyEvent.KEYCODE_F1: Key.F1,