Android Screenshot Detector

ScreenshotDetector.java

package net.gotev.gapp.utils;

import android.content.Context;
import android.net.Uri;
import android.os.Environment;
import android.os.FileObserver;
import android.os.Handler;
import android.util.Log;

import java.io.File;

/**
 * Detects when user performs a screenshot.
 * Permissions needed in Manifest:
 * <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
 * <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
 *
 * For Android 6.0+ also the following runtime permissions are needed to be able to
 * observe for screenshots:
 * Manifest.permission.READ_EXTERNAL_STORAGE
 * Manifest.permission.WRITE_EXTERNAL_STORAGE
 *
 * Usage:
   ScreenshotDetector screenshotDetector =
     new ScreenshotDetector(context, new ScreenshotDetector.OnScreenshotTakenListener() {
        @Override
        public void onScreenshotTaken(Uri uri) {

        }

        @Override
        public void onScreenshotDeleted(Uri uri) {

        }
     });
     screenshotDetector.start();
 *
 * Remember to invoke:
 * screenshotDetector.stop();
 *
 * in the activity's onDestroy Method.
 *
 * @author Alex Gotev ([email protected])
 */
public class ScreenshotDetector extends FileObserver {
    private static final String PATH = Environment.getExternalStorageDirectory().toString() + "/Pictures/Screenshots/";

    public interface OnScreenshotTakenListener {
        void onScreenshotTaken(Uri uri);
        void onScreenshotDeleted(Uri uri);
    }

    private boolean deleteScreenshot = false;
    private OnScreenshotTakenListener mListener;
    private String mLastTakenPath;
    private Handler mainThreadHandler;

    public ScreenshotDetector(Context context, OnScreenshotTakenListener listener) {
        super(PATH, FileObserver.CLOSE_WRITE);
        mainThreadHandler = new Handler(context.getMainLooper());
        mListener = listener;
    }

    @Override
    public void onEvent(int event, String path) {
        Log.d(getClass().getSimpleName(), "Event:" + event + "\t" + path);

        if (path == null || event != FileObserver.CLOSE_WRITE)
            Log.d(getClass().getSimpleName(), "Not important");
        else if (mLastTakenPath != null && path.equalsIgnoreCase(mLastTakenPath))
            Log.d(getClass().getSimpleName(), "This event has been observed before.");
        else {
            mLastTakenPath = path;
            File file = new File(PATH + path);

            if (deleteScreenshot) {
                if (file.exists())
                    file.delete();

                if (mListener != null)
                    mainThreadHandler.post(new Runnable() {
                        @Override
                        public void run() {
                            mListener.onScreenshotDeleted(Uri.fromFile(file));
                        }
                    });

            } else {
                if (mListener != null)
                    mainThreadHandler.post(new Runnable() {
                        @Override
                        public void run() {
                            mListener.onScreenshotTaken(Uri.fromFile(file));
                        }
                    });
            }
        }
    }

    public void start() {
        super.startWatching();
    }

    public void stop() {
        super.stopWatching();
    }

    public void deleteScreenshot(boolean deleteScreenshot) {
        this.deleteScreenshot = deleteScreenshot;
    }

}

@gotev Could you add a license statement here?