Android gestures detection sample code

I recently wanted to implement all the gestures and motion detection in my project such as onFling (swipeup, swipe down), onLongPress, singletap, showpress context menu etc in android and after searching for a long while did not find any sample program that has all the methods as example mainly for onFling and so i made a sample program with all these see the below code

package testt.manju.com;

import android.app.Activity;
import android.graphics.Color;
import android.os.Bundle;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.GestureDetector.OnGestureListener;
import android.widget.LinearLayout;
import android.widget.TextView;
import android.widget.Toast;

public class gridd extends Activity implements OnGestureListener
{ private LinearLayout main; private TextView viewA;

private static final int SWIPE_MIN_DISTANCE = 120;
private static final int SWIPE_MAX_OFF_PATH = 250;
private static final int SWIPE_THRESHOLD_VELOCITY = 200;


private GestureDetector gestureScanner;
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
gestureScanner = new GestureDetector(this);
main = new LinearLayout(this);
main.setBackgroundColor(Color.GRAY);
main.setLayoutParams(new LinearLayout.LayoutParams(320,480));
viewA = new TextView(this);
viewA.setBackgroundColor(Color.YELLOW);
viewA.setTextColor(Color.BLACK);
viewA.setTextSize(16);
viewA.setLayoutParams(new LinearLayout.LayoutParams(320,80));
main.addView(viewA);
setContentView(main);
}
@Override
public boolean onTouchEvent(MotionEvent me)
{
return gestureScanner.onTouchEvent(me);
}
@Override
public boolean onDown(MotionEvent e)
{
viewA.setText("-" + "DOWN" + "-");
return true;
}
@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY)
{
try {
if (Math.abs(e1.getY() - e2.getY()) > SWIPE_MAX_OFF_PATH)
return false;
// right to left swipe
if(e1.getX() - e2.getX() > SWIPE_MIN_DISTANCE && Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) {
Toast.makeText(getApplicationContext(), "Left Swipe", Toast.LENGTH_SHORT).show();
} else if (e2.getX() - e1.getX() > SWIPE_MIN_DISTANCE && Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) {
Toast.makeText(getApplicationContext(), "Right Swipe", Toast.LENGTH_SHORT).show();
}
else if(e1.getY() - e2.getY() > SWIPE_MIN_DISTANCE && Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) {
Toast.makeText(getApplicationContext(), "Swipe up", Toast.LENGTH_SHORT).show();
} else if (e2.getY() - e1.getY() > SWIPE_MIN_DISTANCE && Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) {
Toast.makeText(getApplicationContext(), "Swipe down", Toast.LENGTH_SHORT).show();
}
} catch (Exception e) {
// nothing
}

return true;
}
@Override
public void onLongPress(MotionEvent e)
{
Toast mToast = Toast.makeText(getApplicationContext(), "Long Press", Toast.LENGTH_SHORT);
mToast.show();
}
@Override
public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY)
{
viewA.setText("-" + "SCROLL" + "-");
return true;
}
@Override
public void onShowPress(MotionEvent e)
{
viewA.setText("-" + "SHOW PRESS" + "-");
} @Override
public boolean onSingleTapUp(MotionEvent e) {
Toast mToast = Toast.makeText(getApplicationContext(), "Single Tap", Toast.LENGTH_SHORT);
mToast.show();
return true;
}
}

you can change the threshold, swipe distance and max swip path for onFling Method as per your requirements if the code working mail me or you can suggest improvements