GestureDetectorジェスチャー認識--メモ

public class MainActivity extends Activity {

    private TextView tv;

    private GestureDetector mGestureDetector;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        tv = (TextView) findViewById(R.id.id_imageview);

        mGestureDetector = new GestureDetector(new MyGestrueListener());

        tv.setOnTouchListener(new View.OnTouchListener() {

            @Override//         Event  
            public boolean onTouch(View v, MotionEvent event) {

                mGestureDetector.onTouchEvent(event);

                return true;
            }
        });

    }

    class MyGestrueListener extends GestureDetector.SimpleOnGestureListener {
        @Override
        public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {

            if (e1.getX() - e2.getX() > 50) {
                Toast.makeText(MainActivity.this, "    ", Toast.LENGTH_SHORT).show();
            } else if ((e2.getX() - e1.getX() > 50)) {
                Toast.makeText(MainActivity.this, "    ", Toast.LENGTH_SHORT).show();
            }

            return super.onFling(e1, e2, velocityX, velocityY);
        }
    }


}