Android Swipe on List

I had the same problem and I didn’t find my answer here.

I wanted to detect a swipe action in ListView item and mark it as swiped, while continue to support OnItemClick and OnItemLongClick.

Here is me solution:

1st The SwipeDetector class:

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

public class SwipeDetector implements View.OnTouchListener {

    public static enum Action {
        LR, // Left to Right
        RL, // Right to Left
        TB, // Top to bottom
        BT, // Bottom to Top
        None // when no action was detected
    }

    private static final String logTag = "SwipeDetector";
    private static final int MIN_DISTANCE = 100;
    private float downX, downY, upX, upY;
    private Action mSwipeDetected = Action.None;

    public boolean swipeDetected() {
        return mSwipeDetected != Action.None;
    }

    public Action getAction() {
        return mSwipeDetected;
    }

    @Override
    public boolean onTouch(View v, MotionEvent event) {
        switch (event.getAction()) {
        case MotionEvent.ACTION_DOWN:
            downX = event.getX();
            downY = event.getY();
            mSwipeDetected = Action.None;
            return false; // allow other events like Click to be processed
        case MotionEvent.ACTION_UP:
            upX = event.getX();
            upY = event.getY();

            float deltaX = downX - upX;
            float deltaY = downY - upY;

            // horizontal swipe detection
            if (Math.abs(deltaX) > MIN_DISTANCE) {
                // left or right
                if (deltaX < 0) {
                    Log.i(logTag, "Swipe Left to Right");
                    mSwipeDetected = Action.LR;
                    return false;
                }
                if (deltaX > 0) {
                    Log.i(logTag, "Swipe Right to Left");
                    mSwipeDetected = Action.RL;
                    return false;
                }
            } else if (Math.abs(deltaY) > MIN_DISTANCE) { // vertical swipe
                                                            // detection
                // top or down
                if (deltaY < 0) {
                    Log.i(logTag, "Swipe Top to Bottom");
                    mSwipeDetected = Action.TB;
                    return false;
                }
                if (deltaY > 0) {
                    Log.i(logTag, "Swipe Bottom to Top");
                    mSwipeDetected = Action.BT;
                    return false;
                }
            }
            return false;
        }
        return false;
    }
}

2nd I use the swipe detector class in the list view:

    final ListView lv = getListView();
    final SwipeDetector swipeDetector = new SwipeDetector();
    lv.setOnTouchListener(swipeDetector);
    lv.setOnItemClickListener(new OnItemClickListener() {
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                if (swipeDetector.swipeDetected()){
                    // do the onSwipe action 
                } else {
                    // do the onItemClick action
                }
            }
    });
    lv.setOnItemLongClickListener(new OnItemLongClickListener() {
        @Override
        public boolean onItemLongClick(AdapterView<?> parent, View view,int position, long id) {
            if (swipeDetector.swipeDetected()){
                // do the onSwipe action 
            } else {
                // do the onItemLongClick action
            }
        }
    });

This way I can support 3 actions – swipe, click, long click and I can use the ListView item info.

ADDED LATER:

Since ListView catches a scrolling action, it is sometimes hard to swipe. To fix it, I made the following change to SwipeDetector.onTouch:

public boolean onTouch(View v, MotionEvent event) {
    switch (event.getAction()) {
        case MotionEvent.ACTION_DOWN: {
            downX = event.getX();
            downY = event.getY();
            mSwipeDetected = Action.None;
            return false; // allow other events like Click to be processed
        }
        case MotionEvent.ACTION_MOVE: {
            upX = event.getX();
            upY = event.getY();

            float deltaX = downX - upX;
            float deltaY = downY - upY;

            // horizontal swipe detection
            if (Math.abs(deltaX) > HORIZONTAL_MIN_DISTANCE) {
                // left or right
                if (deltaX < 0) {
                    Log.i(logTag, "Swipe Left to Right");
                    mSwipeDetected = Action.LR;
                    return true;
                }
                if (deltaX > 0) {
                    Log.i(logTag, "Swipe Right to Left");
                    mSwipeDetected = Action.RL;
                    return true;
                }
            } else 

            // vertical swipe detection
            if (Math.abs(deltaY) > VERTICAL_MIN_DISTANCE) {
                // top or down
                if (deltaY < 0) {
                    Log.i(logTag, "Swipe Top to Bottom");
                    mSwipeDetected = Action.TB;
                    return false;
                }
                if (deltaY > 0) {
                    Log.i(logTag, "Swipe Bottom to Top");
                    mSwipeDetected = Action.BT;
                    return false;
                }
            } 
            return true;
        }
    }
    return false;
}

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