How to check the screenshot?

As you mentioned in your question when using FileObserverNo guarantees that on all devices that path will be the same.

The Android API does not have a fixed route for screenshots, but

File pix = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES);
File screenshots = new File(pix, "Screenshots");

It could work. That's what ICS uses as a route.

So what I can think of to do then is create a list of paths for each device and bind them with Build .

When using FileObserver , only monitor the file creation event on the screenshot directory.

String path = Environment.getExternalStorageDirectory()
        + File.separator + Environment.DIRECTORY_PICTURES
        + File.separator + "Screenshots" + File.separator;
Log.d(TAG, path);

FileObserver fileObserver = new FileObserver(path, FileObserver.CREATE) {
    @Override
    public void onEvent(int event, String path) {
        Log.d(TAG, event + " " + path);
    }
};

fileObserver.startWatching();

Don't forget to declare the corresponding permissions to access the content on the SD card.

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />

Another solution to detect the screenshot is to use ContentObserver, because there will be a record inserted in the system media database after the screenshot. The following is the code snippet used to monitor the event ContentObserver. When using , you don't need to declare the / ContentObserverpermissions , but you do need to do some filtering on the filename to make sure it's a screenshot event.writeread external storage

HandlerThread handlerThread = new HandlerThread("content_observer");
    handlerThread.start();
    final Handler handler = new Handler(handlerThread.getLooper()) {

        @Override
        public void handleMessage(Message msg) {
            super.handleMessage(msg);
        }
    };

    getContentResolver().registerContentObserver(
            MediaStore.Images.Media.EXTERNAL_CONTENT_URI,
            true,
            new ContentObserver(handler) {
                @Override
                public boolean deliverSelfNotifications() {
                    Log.d(TAG, "deliverSelfNotifications");
                    return super.deliverSelfNotifications();
                }

                @Override
                public void onChange(boolean selfChange) {
                    super.onChange(selfChange);
                }

                @Override
                public void onChange(boolean selfChange, Uri uri) {
                    Log.d(TAG, "onChange " + uri.toString());
                    if (uri.toString().matches(MediaStore.Images.Media.EXTERNAL_CONTENT_URI.toString() + "/[0-9]+")) {

                        Cursor cursor = null;
                        try {
                            cursor = getContentResolver().query(uri, new String[] {
                                    MediaStore.Images.Media.DISPLAY_NAME,
                                    MediaStore.Images.Media.DATA
                            }, null, null, null);
                            if (cursor != null && cursor.moveToFirst()) {
                                final String fileName = cursor.getString(cursor.getColumnIndex(MediaStore.Images.Media.DISPLAY_NAME));
                                final String path = cursor.getString(cursor.getColumnIndex(MediaStore.Images.Media.DATA));
                                // TODO: aplicar filtro en el nombre del archivo para asegurarse de que sea un evento de captura de pantalla
                                Log.d(TAG, "screen shot added " + fileName + " " + path);
                            }
                        } finally {
                            if (cursor != null)  {
                                cursor.close();
                            }
                        }
                    }
                    super.onChange(selfChange, uri);
                }
            }
    );

If you use this method, you must request READ_EXTERNAL_STORAGEafter the version of Android M, otherwise it will return SecurityException. For more information on: How to request runtime permission, see here .

However this has a problem that when the content watcher has detected the image from the camera (it should be just a screenshot).

To solve this:

ScreenshotDetectionDelegate.java

public class ScreenshotDetectionDelegate {
    private WeakReference<Activity> activityWeakReference;
    private ScreenshotDetectionListener listener;

    public ScreenshotDetectionDelegate(Activity activityWeakReference, ScreenshotDetectionListener listener) {
        this.activityWeakReference = new WeakReference<>(activityWeakReference);
        this.listener = listener;
    }

    public void startScreenshotDetection() {
        activityWeakReference.get()
                .getContentResolver()
                .registerContentObserver(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, true, contentObserver);
    }

    public void stopScreenshotDetection() {
        activityWeakReference.get().getContentResolver().unregisterContentObserver(contentObserver);
    }

    private ContentObserver contentObserver = new ContentObserver(new Handler()) {
        @Override
        public boolean deliverSelfNotifications() {
            return super.deliverSelfNotifications();
        }

        @Override
        public void onChange(boolean selfChange) {
            super.onChange(selfChange);
        }

        @Override
        public void onChange(boolean selfChange, Uri uri) {
            super.onChange(selfChange, uri);
            if (isReadExternalStoragePermissionGranted()) {
                String path = getFilePathFromContentResolver(activityWeakReference.get(), uri);
                if (isScreenshotPath(path)) {
                    onScreenCaptured(path);
                }
            } else {
                onScreenCapturedWithDeniedPermission();
            }
        }
    };

    private void onScreenCaptured(String path) {
        if (listener != null) {
            listener.onScreenCaptured(path);
        }
    }

    private void onScreenCapturedWithDeniedPermission() {
        if (listener != null) {
            listener.onScreenCapturedWithDeniedPermission();
        }
    }

    private boolean isScreenshotPath(String path) {
        return path != null && path.toLowerCase().contains("screenshots");
    }

    private String getFilePathFromContentResolver(Context context, Uri uri) {
        try {
            Cursor cursor = context.getContentResolver().query(uri, new String[]{
                    MediaStore.Images.Media.DISPLAY_NAME,
                    MediaStore.Images.Media.DATA
            }, null, null, null);
            if (cursor != null && cursor.moveToFirst()) {
                String path = cursor.getString(cursor.getColumnIndex(MediaStore.Images.Media.DATA));
                cursor.close();
                return path;
            }
        } catch (IllegalStateException ignored) {
        }
        return null;
    }

    private boolean isReadExternalStoragePermissionGranted() {
        return ContextCompat.checkSelfPermission(activityWeakReference.get(), Manifest.permission.READ_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED;
    }

    public interface ScreenshotDetectionListener {
        void onScreenCaptured(String path);

        void onScreenCapturedWithDeniedPermission();
    }
}

ScreenshotDetectionActivity.java

import android.Manifest;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.widget.Toast;

public abstract class ScreenshotDetectionActivity extends AppCompatActivity implements ScreenshotDetectionDelegate.ScreenshotDetectionListener {
    private static final int REQUEST_CODE_READ_EXTERNAL_STORAGE_PERMISSION = 3009;

    private ScreenshotDetectionDelegate screenshotDetectionDelegate = new ScreenshotDetectionDelegate(this, this);

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        checkReadExternalStoragePermission();
    }

    @Override
    protected void onStart() {
        super.onStart();
        screenshotDetectionDelegate.startScreenshotDetection();
    }

    @Override
    protected void onStop() {
        super.onStop();
        screenshotDetectionDelegate.stopScreenshotDetection();
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        switch (requestCode) {
            case REQUEST_CODE_READ_EXTERNAL_STORAGE_PERMISSION:
                if (grantResults[0] == PackageManager.PERMISSION_DENIED) {
                    showReadExternalStoragePermissionDeniedMessage();
                }
                break;
            default:
                super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        }
    }

    @Override
    public void onScreenCaptured(String path) {
        // Hacer algo cuando se capturó la pantalla
    }

    @Override
    public void onScreenCapturedWithDeniedPermission() {
        // Hacer algo cuando se capturó la pantalla, pero se ha denegado el permiso de lectura de almacenamiento externo
    }

    private void checkReadExternalStoragePermission() {
        if (ContextCompat.checkSelfPermission(this, Manifest.permission.READ_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
            requestReadExternalStoragePermission();
        }
    }

    private void requestReadExternalStoragePermission() {
        ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.READ_EXTERNAL_STORAGE}, REQUEST_CODE_READ_EXTERNAL_STORAGE_PERMISSION);
    }

    private void showReadExternalStoragePermissionDeniedMessage() {
        Toast.makeText(this, "El permiso de lectura de lectura externa ha denegado", Toast.LENGTH_SHORT).show();
    }
}

MainActivity.java

import android.os.Bundle;
import android.view.View;
import android.widget.Toast;

public class MainActivity extends ScreenshotDetectionActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }

    @Override
    public void onScreenCaptured(String path) {
        Toast.make(this, path, Toast.LENGTH_SHORT).show();
    }

    @Override
    public void onScreenCapturedWithDeniedPermission() {
        Toast.make(this, "Por favor, conceda permiso de lectura de lectura externa para la detección de captura de pantalla", Toast.LENGTH_SHORT).show();
    }
}

This code works, but has problems with some devices eg: Android 6.0 on Nexus 7 gives content://media/external/images/media as the uri in onChange, which can't resolve to the file path correctly.

Although the answer does not answer all the needs, but it can be a push base to obtain other ideas, I hope it will serve you. Cheers!

More information can be found in the original question, SO Source: https://stackoverflow.com/questions/29621903/detect-only-screenshot-with-fileobserver-android