SwipeGestureDetector.java

package de.danoeh.antennapod.view;

import android.util.Log;
import android.view.GestureDetector;
import android.view.MotionEvent;

public class SwipeGestureDetector extends GestureDetector.SimpleOnGestureListener {

    private static final String TAG = "SwipeGestureDetector";

    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 final OnSwipeGesture callback;

    public SwipeGestureDetector(OnSwipeGesture callback) {
        this.callback = callback;
    }

    @Override
    public boolean onDown(MotionEvent e) {
        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;
            if (e1.getX() - e2.getX() > SWIPE_MIN_DISTANCE
                    && Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) {
                return callback.onSwipeRightToLeft();
            } else if (e2.getX() - e1.getX() > SWIPE_MIN_DISTANCE
                    && Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) {
                return callback.onSwipeLeftToRight();
            }
        } catch (Exception e) {
            Log.d(TAG, Log.getStackTraceString(e));
        }
        return false;
    }

}