Android calls python through chaquo to get the ui window built by toga, strange error “Failed to create image decoder with message 'unimplemented'”

[andy4lee]

Describe the bug

I need a permanent floating window, so I need to use a service to implement it, not an activity (toga can be called normally，so to prove that the software environment is fine)

FloatingWindowService.java:
package org.beeware.android;

import static android.content.ContentValues.TAG;

import android.app.Notification;
import android.app.NotificationChannel;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.app.Service;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.res.Configuration;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.PixelFormat;
import android.hardware.display.DisplayManager;
import android.hardware.display.VirtualDisplay;
import android.media.Image;
import android.media.ImageReader;
import android.media.projection.MediaProjection;
import android.media.projection.MediaProjectionManager;
import android.os.Build;
import android.os.Handler;
import android.os.IBinder;
import android.util.DisplayMetrics;
import android.util.Log;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.view.MenuItem;
import android.view.Menu;

import android.view.WindowManager;
import android.widget.Button;
import android.widget.TextView;

import androidx.annotation.Nullable;

import java.util.Arrays;
import java.util.Objects;

import com.chaquo.python.Kwarg;
import com.chaquo.python.PyException;
import com.chaquo.python.Python;
import com.chaquo.python.PyObject;
import com.chaquo.python.android.AndroidPlatform;
import com.example.uiapp.R;

public class FloatingWindowService extends Service {

public static final String TAG = "FloatingWindowService";
private WindowManager windowManager;
private ViewGroup floatView;
private int LAYOUT_TYPE;
private WindowManager.LayoutParams floatWindowLayoutParam;
private static PyObject pythonApp;
	
@SuppressWarnings("unused")
public static void setPythonApp(IPythonApp app) {
    pythonApp = PyObject.fromJava(app);
}

public void onCreate() {
    super.onCreate();
    Log.d(TAG, "FloatingWindowService onCreate()");
    updateFloatingWindowContent(null);
	//createFloatingWindow();
	//startTogaActivity();
	userCode("onCreate");
}
private void updateFloatingWindowContent(TextView textView) {
    // Make sure Python is initialized
    if (!Python.isStarted()) {
        AndroidPlatform platform = new AndroidPlatform(this);
        platform.redirectStdioToLogcat();
        Python.start(platform);
    }
    Python py = Python.getInstance();
    Log.d(TAG, "Running Python code to update floating window content");

    // Call Python function to get content
    py.getModule("runpy").callAttr(
            "run_module",
            "uiapp.__main__",
            new Kwarg("run_name", "__main__"),
            new Kwarg("alter_sys", true)
    );
    // Update the view (run on UI thread)
    //textView.post(() -> textView.setText(content));
}

private void startTogaActivity() {
	Intent intent = new Intent(this, TogaActivity.class);
	intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
	startActivity(intent);
}
private int mScreenWidth;
private int mScreenHeight;

private void createFloatingWindow() {
	LayoutInflater inflater = (LayoutInflater) getBaseContext().getSystemService(LAYOUT_INFLATER_SERVICE);
    floatView = (ViewGroup) inflater.inflate(R.layout.activity_main, null);
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
        LAYOUT_TYPE = WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY;
    } else {
        LAYOUT_TYPE = WindowManager.LayoutParams.TYPE_TOAST;
    }
	
    WindowManager windowManager = (WindowManager) getSystemService(WINDOW_SERVICE);
	
	DisplayMetrics metrics = new DisplayMetrics();
    windowManager.getDefaultDisplay().getMetrics(metrics);
    mScreenWidth = metrics.widthPixels;
    mScreenHeight = 200;

    // Determine the correct window type
    WindowManager.LayoutParams layoutParams;
    if (android.os.Build.VERSION.SDK_INT >= 26) {
        // For Android 8.0 and above
        layoutParams = new WindowManager.LayoutParams(
                mScreenWidth,
                mScreenHeight,
                LAYOUT_TYPE,
                WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE | WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL,
                android.graphics.PixelFormat.TRANSLUCENT
        );
    } else {
        // For below Android 8.0
        layoutParams = new WindowManager.LayoutParams(
                WindowManager.LayoutParams.WRAP_CONTENT,
                WindowManager.LayoutParams.WRAP_CONTENT,
                WindowManager.LayoutParams.TYPE_PHONE,
                WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE | WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL,
                android.graphics.PixelFormat.TRANSLUCENT
        );
    }

	layoutParams.gravity = Gravity.TOP | Gravity.CENTER;
    layoutParams.x = 0;
    layoutParams.y = 0;

    // Create a placeholder view
    TextView textView = new TextView(this);
    textView.setText("Loading...");

    // Add the view to the window
    windowManager.addView(textView, layoutParams);
	Log.d(TAG, "Add the view to the window");
    // Initialize Python and request content
    updateFloatingWindowContent(textView);
}



MediaProjectionManager mediaProjectionManager;
MediaProjection mMediaProjection;

@Override
public int onStartCommand(final Intent intent, int flags, int startId) {
    createNotificationChannel();
    int mResultCode = intent.getIntExtra("code", -1);
    Intent mResultData = intent.getParcelableExtra("data");
    mediaProjectionManager = (MediaProjectionManager)getSystemService(Context.MEDIA_PROJECTION_SERVICE);
    mMediaProjection = mediaProjectionManager.getMediaProjection(mResultCode, Objects.requireNonNull(mResultData));
    Log.e(TAG, "mMediaProjection created: " + mMediaProjection);
    return super.onStartCommand(intent, flags, startId);
}

private void createNotificationChannel() {
    Notification.Builder builder = new Notification.Builder(this.getApplicationContext()); 
    Intent nfIntent = new Intent(this, MainActivity.class); 
    builder.setContentIntent(PendingIntent.getActivity(this, 0, nfIntent, PendingIntent.FLAG_IMMUTABLE)) 
            .setLargeIcon(BitmapFactory.decodeResource(this.getResources(), R.mipmap.ic_launcher)) 
            .setSmallIcon(R.mipmap.ic_launcher) 
            .setContentText("is running......") 
            .setWhen(System.currentTimeMillis()); 

    if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
        builder.setChannelId("notification_id");
    }

    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
        NotificationManager notificationManager = (NotificationManager)getSystemService(NOTIFICATION_SERVICE);
        NotificationChannel channel = new NotificationChannel("notification_id", "notification_name", NotificationManager.IMPORTANCE_LOW);
        notificationManager.createNotificationChannel(channel);
    }
    Notification notification = builder.build(); 
    notification.defaults = Notification.DEFAULT_SOUND; 
    startForeground(110, notification);
}


public void onConfigurationChanged(Configuration newConfig) {
    Log.d(TAG, "onConfigurationChanged() start");
    super.onConfigurationChanged(newConfig);
    userCode("onConfigurationChanged", newConfig);
    Log.d(TAG, "onConfigurationChanged() complete");
}

public boolean onOptionsItemSelected(MenuItem menuitem) {
    Log.d(TAG, "onOptionsItemSelected() start");
    PyObject pyResult = userCode("onOptionsItemSelected", menuitem);
    boolean result = (pyResult == null) ? false : pyResult.toBoolean();
    Log.d(TAG, "onOptionsItemSelected() complete");
    return result;
}

public boolean onPrepareOptionsMenu(Menu menu) {
    Log.d(TAG, "onPrepareOptionsMenu() start");
    PyObject pyResult = userCode("onPrepareOptionsMenu", menu);
    boolean result = (pyResult == null) ? false : pyResult.toBoolean();
    Log.d(TAG, "onPrepareOptionsMenu() complete");
    return result;
}


private PyObject userCode(String methodName, Object... args) {
    if (pythonApp == null) {
        // Could be a non-graphical app such as Python-support-testbed.
        return null;
    }
    try {
        if (pythonApp.containsKey(methodName)) {
            return pythonApp.callAttr(methodName, args);
        } else {
            // Handle the case where the method doesn't exist
            return null;
        }
    } catch (PyException e) {
        if (e.getMessage().startsWith("NotImplementedError")) {
            return null;
        }
        throw e;
    }
}


@Nullable
@Override
public IBinder onBind(Intent intent) {
    return null;
}

}

Steps to reproduce

1. briefcase run android -d emulator-5554
2. Go to app
3. Click on 'button'
4. See error on console

Expected behavior

a permanent floating window by toga

Screenshots

Environment

• Operating System: windows 10.0.17763.316
• Python version: 3.11.2
• Software versions:
  • Briefcase: 0.3.18
  • Toga: 0.4.5
  • ...

Logs

�[38;5;75mD/FloatingWindowService: Running Python code to update floating window content�[0m
�[38;5;40mI/python.stdout: WARNING: Can't find app icon; falling back to default icon�[0m
�[38;5;166mW/m.example.uiap: Accessing hidden method Ljava/io/FileDescriptor;->setInt$(I)V (greylist,core-platform-api, JNI, allowed)�[0m
�[38;5;166mW/m.example.uiap: Accessing hidden method Landroid/os/Handler;->(Landroid/os/Looper;Landroid/os/Handler$Callback;Z)V (greylist, JNI, allowed)�[0m
�[38;5;166mW/m.example.uiap: Accessing hidden method Landroid/os/Handler;->(Z)V (greylist, JNI, allowed)�[0m
�[38;5;40mI/python.stdout: Python app launched & stored in Android Activity class�[0m
�[38;5;75mD/skia : --- Failed to create image decoder with message 'unimplemented'�[0m

Additional context

No response