Swipe to dismiss view. gotta put this in a library

gistfile1.java

package com.blah.lol.swipetodismiss;

import android.content.Context;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.VelocityTracker;
import android.view.View;
import android.widget.FrameLayout;

import com.blah.lol.R;

/**
 * Created by fdoyle on 10/28/13.
 */
public class SwipeAwayView extends FrameLayout {

    public static final int SWIPED_RIGHT = 1;
    public static final int SWIPED_LEFT = -1;
    public static final int SWIPED_CENTER = 0;
    public View topView;
    public View bottomView;
    VelocityTracker tracker;
    int swipedPosition;

    OnItemSwipedListener listener;

    int index;

    int pointerId;

    int marginInPixels = 200;


    public SwipeAwayView(Context context) {
        super(context);

    }

    public SwipeAwayView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public void setOnItemSwipedListener(OnItemSwipedListener listener, int index) {
        this.listener = listener;
        this.index = index;
    }

    public void setupView() {
        topView = getChildAt(1);
        bottomView = getChildAt(0);
        bottomView.setVisibility(INVISIBLE);
    }


    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        setupView();
    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent event) {
        float currentX = event.getX();
        switch (event.getAction()) {
            case MotionEvent.ACTION_DOWN:
                tracker = VelocityTracker.obtain();
                pointerId = event.getPointerId(0);
                startX = currentX;
                return false;
            case MotionEvent.ACTION_MOVE:
                float topViewLeftBound = topView.getX();
                float topViewRightBound = topViewLeftBound + topView.getWidth();
                if (Math.abs(startX - event.getX()) > 10 && startX < topViewRightBound && startX > topViewLeftBound)
                    return true;
                return false;
            case MotionEvent.ACTION_UP:
                return false;
            default:
                return false;
        }
    }

    float startX;
    float lastX;

    public void setSwipedPositionAnimated(int position) {
        swipedPosition = position;
        topView.animate().translationX(swipedPosition * (getWidth() - marginInPixels)).setDuration(200).withEndAction(new Runnable() {
            @Override
            public void run() {
                if (bottomView != null)
                    if (swipedPosition == SWIPED_CENTER) {
                        bottomView.setVisibility(INVISIBLE);
                    } else {
                        bottomView.setVisibility(VISIBLE);
                    }
                if (listener != null)
                    listener.onItemSwiped(index, swipedPosition);

            }
        }).start();
    }

    public void setSwipedPositionImmediate(int position) {
        swipedPosition = position;
        topView.animate().translationX(swipedPosition * (getWidth() - marginInPixels)).setDuration(0).withEndAction(new Runnable() {
            @Override
            public void run() {
                if(bottomView != null)
                    if (swipedPosition == SWIPED_CENTER) {
                        bottomView.setVisibility(INVISIBLE);
                    } else {
                        bottomView.setVisibility(VISIBLE);
                    }
                if (listener != null)
                    listener.onItemSwiped(index, swipedPosition);

            }
        }).start();
    }


    @Override
    public boolean onTouchEvent(MotionEvent event) {
        float currentX = event.getX();
        switch (event.getAction()) {
            case MotionEvent.ACTION_DOWN: //because events are not intercepted until after ACTION_DOWN, this will never be reached

                return false;

            case MotionEvent.ACTION_MOVE:
                if (event.getPointerId(0) != 0)
                    return false;
                tracker.addMovement(event);
                if (lastX != 0) {
                    topView.animate().translationXBy(currentX - lastX).setDuration(0).start();
                    bottomView.setVisibility(VISIBLE);
                    getParent().requestDisallowInterceptTouchEvent(true);
                }
                lastX = currentX;
                return true;
            case MotionEvent.ACTION_CANCEL:
            case MotionEvent.ACTION_POINTER_UP:
            case MotionEvent.ACTION_UP:
                if (event.getPointerId(0) != 0)
                    return false;
                getParent().requestDisallowInterceptTouchEvent(false);
                tracker.computeCurrentVelocity(1);
                boolean flinging = Math.abs(tracker.getXVelocity()) > 3;
                boolean draggedFarEnough = Math.abs(startX - currentX) > getWidth() / 2.5;
                boolean xIncreasing;
                if (flinging) {
                    xIncreasing = tracker.getXVelocity() > 0;
                } else {
                    xIncreasing = startX < currentX;
                }

                final int direction;
                if (xIncreasing) {
                    direction = SWIPED_RIGHT;
                } else {
                    direction = SWIPED_LEFT;
                }
                if ((flinging || draggedFarEnough)) {
                    if (swipedPosition == SWIPED_CENTER) { //if it's center, move it in direction
                        swipedPosition += direction;
                    } else if (swipedPosition + direction == SWIPED_CENTER) { //if moving it in direction would center it, center it.
                        swipedPosition = SWIPED_CENTER;
                    }

                    //move to resting state in appropriate position
                    topView.animate().translationX(swipedPosition * (getWidth() - marginInPixels)).setDuration(200).withEndAction(new Runnable() {
                        @Override
                        public void run() {
                            if(bottomView == null) {

                            } else if (swipedPosition == SWIPED_CENTER) {
                                bottomView.setVisibility(INVISIBLE);
                            } else {
                                bottomView.setVisibility(VISIBLE);
                            }
                            if (listener != null)
                                listener.onItemSwiped(index, swipedPosition);

                        }
                    }).start();

                } else {
                    topView.animate().translationX(swipedPosition * (getWidth() - marginInPixels)).setDuration(200).withEndAction(new Runnable() {
                        @Override
                        public void run() {
                            if (swipedPosition == SWIPED_CENTER && bottomView != null)
                                bottomView.setVisibility(INVISIBLE);

                        }
                    }).start();
                }
                tracker.clear();
                tracker.recycle();
                tracker = null;
                lastX = 0;
                startX = 0;
                return true;
            default:
                return false;
        }
    }

    public interface OnItemSwipedListener {
        public void onItemSwiped(int index, int direction);

    }
}