2 finger swipe in android

问题:

I tried implementing 2 finger swipe using onFling method of SimpleOnGestureListener. However,I found that SimpleOnGestureListener doesn't support two finger touch.

How can I work it out ?

回答1:

My Solution works, but its quite ugly to use a public static int to count how many fingers there are. i had to set fingercount back to one after i flinged with two fingers because i couldnot get the action_pointer_down for one finger anymore... i dont know why... but this solution would also work for more fingers... hope someone can use it in the feature

public class RemoteFragment extends Fragment{

public static int fingercount = 1;    

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {

    final GestureDetector gdt = new GestureDetector(getActivity(),
            new RemoteGestureListener());

    View view = inflater.inflate(R.layout.gestures, container, false);

    view.setOnTouchListener(new OnTouchListener() {

        @Override
        public boolean onTouch(final View view, final MotionEvent event) {
            int action = event.getAction();

            switch (action & MotionEvent.ACTION_MASK) {
            case MotionEvent.ACTION_POINTER_DOWN:
                Log.d(TAG,
                        "Pointer-Count ="
                                + String.valueOf(fingerCount = event
                                        .getPointerCount()));

                break;
            }
            gdt.onTouchEvent(event);
            return true;
        }
    });
    return view;
}
}

public class RemoteGestureListener implements OnGestureListenerr {

private final static String TAG = "RemoteGestureListener";

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


public RemoteGestureListener() {
}

@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
        float velocityY) {

    Log.d(TAG, "onFling");
    if (e1.getX() - e2.getX() > SWIPE_MIN_DISTANCE
            && Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) {
        if (RemoteFragment.fingerCount == 1) {
            Log.d(TAG, "Left Swipe");
        } else {
            Log.d(TAG, "Left xFinger Swipe");
            RemoteFragment.fingerCount = 1;
        }
        return true; // Right to left
    } else if (e2.getX() - e1.getX() > SWIPE_MIN_DISTANCE
            && Math.abs(velocityX) > SWIPE_THRESHOLD_VELOCITY) {
        if (RemoteFragment.fingerCount == 1) {
            Log.d(TAG, "Right Swipe");
        } else {
            Log.d(TAG, "Right xFinger Swipe");
            RemoteFragment.fingerCount = 1;
        }
        return true; // Left to right
    }

    if (e1.getY() - e2.getY() > SWIPE_MIN_DISTANCE
            && Math.abs(velocityY) > SWIPE_THRESHOLD_VELOCITY) {
        if (RemoteFragment.fingerCount == 1) {
            Log.d(TAG, "Top Swipe");
        } else {
            Log.d(TAG, "Top xFinger Swipe");
            RemoteFragment.fingerCount = 1;
        }
        return true; // Bottom to top
    } else if (e2.getY() - e1.getY() > SWIPE_MIN_DISTANCE
            && Math.abs(velocityY) > SWIPE_THRESHOLD_VELOCITY) {
        if (RemoteFragment.fingerCount == 1) {
            Log.d(TAG, "Bottom Swipe");
        } else {
            Log.d(TAG, "Bottom xFinger Swipe");
            RemoteFragment.fingerCount = 1;
        }
        return true;
    }
    return true;
}

回答2:

You could try to use OnTouchListener with MotionEvent.ACTION_POINTER_DOWN like this:

 button.setOnTouchListener(new View.OnTouchListener() {
        public boolean onTouch(View view, MotionEvent motionEvent) {
            int action = motionEvent.getAction();

            switch(action & MotionEvent.ACTION_MASK)
            {
                case MotionEvent.ACTION_POINTER_DOWN:
                    Toast.makeText(MyActivity.this, " Two Fingers Tapped Once. Yeeeyy :)", 0).show();

                    // set the mTwoFingersTapped flag to TRUE when we tap with 2 fingers at once
                    mTwoFingersTapped = true;
                    break;
            }
            return false;
        }
    });

Here is a tutorial which explains how to do it if you need more details. I hope it will help.

回答3:

I had made a library some time ago that makes implementing 1/multi finger swipes very easy.

You can find more detailed documentation of the API here A sample implementation can be found here

The part that you want to look at is

ImageView mv = (ImageView) findViewById(R.id.myview);
final TextView grtv = (TextView) findViewById(R.id.gestureResultTextView);
SimpleFingerGestures.DEBUG = true;
SimpleFingerGestures.CONSUME_TOUCH_EVENTS = true;
SimpleFingerGestures sfg = new SimpleFingerGestures();
sfg.setOnFingerGestureListener(new SimpleFingerGestures.OnFingerGestureListener() {
@Override
public boolean onSwipeUp(int fingers, long gestureDuration) {
grtv.setText("swiped " + fingers + " up");
return false;
}
@Override
public boolean onSwipeDown(int fingers, long gestureDuration) {
grtv.setText("swiped " + fingers + " down");
return false;
}
@Override
public boolean onSwipeLeft(int fingers, long gestureDuration) {
grtv.setText("swiped " + fingers + " left");
return false;
}
@Override
public boolean onSwipeRight(int fingers, long gestureDuration) {
grtv.setText("swiped " + fingers + " right");
return false;
}
@Override
public boolean onPinch(int fingers, long gestureDuration) {
grtv.setText("pinch");
return false;
}
@Override
public boolean onUnpinch(int fingers, long gestureDuration) {
grtv.setText("unpinch");
return false;
}
});
mv.setOnTouchListener(sfg);