Easy class that shows floating view in right bottom corner of ABsListView

DirectionalScrollListener.java

package android.widget;

import android.os.CountDownTimer;
import android.view.View;

/**
 * Created by a557114 on 20/06/2014.
 */
public class DirectionalScrollListener implements AbsListView.OnScrollListener {

    private int oldTop;
    private int oldFirstVisibleItem;

    private OnDetectScrollListener onDetectScrollListener;
    private AbsListView.OnScrollListener handlerScroll;

    private long countdownStop;
    private boolean enabled;

    public DirectionalScrollListener(OnDetectScrollListener onDetectScrollListener) {
        this.onDetectScrollListener = onDetectScrollListener;
        this.countdownStop = -1;
    }

    public DirectionalScrollListener(OnCancelableDetectScrollListener onDetectScrollListener, AbsListView.OnScrollListener handlerScroll, long countdownStop) {
        this.onDetectScrollListener = onDetectScrollListener;
        this.handlerScroll = handlerScroll;
        this.countdownStop = countdownStop;
    }

    @Override
    public void onScrollStateChanged(AbsListView view, int scrollState) {

        if (handlerScroll != null) {
            handlerScroll.onScrollStateChanged(view, scrollState);
        }

        enabled = scrollState == SCROLL_STATE_TOUCH_SCROLL;

        if (scrollState == SCROLL_STATE_IDLE && countdownStop > -1) {
            new CountDownTimer(countdownStop, 10) {
                @Override
                public void onTick(long millisUntilFinished) {

                }

                @Override
                public void onFinish() {
                    if (onDetectScrollListener != null && onDetectScrollListener instanceof OnCancelableDetectScrollListener) {
                        ((OnCancelableDetectScrollListener) onDetectScrollListener).onScrollStop();
                    }
                }
            }.start();
        }
    }

    @Override
    public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
        if (handlerScroll != null) {
            handlerScroll.onScroll(view, firstVisibleItem, visibleItemCount, totalItemCount);
        }
        if (onDetectScrollListener != null) {
            onDetectedListScroll(view, firstVisibleItem);
        }
    }

    private void onDetectedListScroll(AbsListView absListView, int firstVisibleItem) {
        if (enabled) {
            View view = absListView.getChildAt(0);
            int top = (view == null) ? 0 : view.getTop();

            if (firstVisibleItem == oldFirstVisibleItem) {
                if (top > oldTop) {
                    up();
                } else if (top < oldTop) {
                    down();
                }
            } else {
                if (firstVisibleItem < oldFirstVisibleItem) {
                    up();
                } else {
                    down();
                }
            }

            oldTop = top;
            oldFirstVisibleItem = firstVisibleItem;
        }
    }

    private void up() {
        if (onDetectScrollListener != null) {
            onDetectScrollListener.onUpScrolling();
        }

        if (handlerScroll != null && handlerScroll instanceof OnDetectScrollListener) {
            ((OnDetectScrollListener) handlerScroll).onUpScrolling();
        }
    }

    private void down() {
        if (onDetectScrollListener != null) {
            onDetectScrollListener.onDownScrolling();
        }

        if (handlerScroll != null && handlerScroll instanceof OnDetectScrollListener) {
            ((OnDetectScrollListener) handlerScroll).onDownScrolling();
        }
    }

    public interface OnDetectScrollListener {

        void onUpScrolling();

        void onDownScrolling();
    }

    public interface OnCancelableDetectScrollListener extends OnDetectScrollListener {
        void onScrollStop();
    }

    public OnDetectScrollListener getOnDetectScrollListener() {
        return onDetectScrollListener;
    }

    public void setOnDetectScrollListener(OnDetectScrollListener onDetectScrollListener) {
        this.onDetectScrollListener = onDetectScrollListener;
    }

    public AbsListView.OnScrollListener getHandlerScroll() {
        return handlerScroll;
    }

    public void setHandlerScroll(AbsListView.OnScrollListener handlerScroll) {
        this.handlerScroll = handlerScroll;
    }

    public long getCountdownStop() {
        return countdownStop;
    }

    public void setCountdownStop(long countdownStop) {
        this.countdownStop = countdownStop;
    }
}

GoatLayout.java

package android.widget;

import android.animation.Animator;
import android.animation.ObjectAnimator;
import android.animation.PropertyValuesHolder;
import android.animation.ValueAnimator;
import android.content.Context;
import android.util.AttributeSet;
import android.view.View;
import android.view.ViewGroup;

/**
 * Created by a557114 on 20/06/2014.
 */
public class GoatLayout extends FrameLayout implements DirectionalScrollListener.OnCancelableDetectScrollListener {

    private View floatView;
    private ObjectAnimator upAnimation;
    private ObjectAnimator downAnimation;
    private float fraction = 1.0f;
    private FLOAT_STATE float_state;

    private int marginRight;
    private int marginBottom;
    private float density;
    private long timeShowOnStop;
    private AbsListView.OnScrollListener handlerScroll;
    private DirectionalScrollListener directionalScrollListener;

    public GoatLayout(Context context) {
        super(context);
        init();
    }

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

    public GoatLayout(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        init();
    }

    private void init() {
        density = getResources().getDisplayMetrics().density;
        marginRight = 10;
        marginBottom = 10;
        timeShowOnStop = 400;
    }

    public void setFloatView(View floatView) {
        this.floatView = floatView;
        if (floatView.getLayoutParams() == null) {
            int squareSize = (int) (50 * density);
            LayoutParams layoutParams = new LayoutParams(squareSize, squareSize);
            floatView.setLayoutParams(layoutParams);
        }
        float_state = FLOAT_STATE.VISIBLE;
        addView(floatView);
        postInvalidate();
    }

    @Override
    public void addView(View child, ViewGroup.LayoutParams params) {
        super.addView(child, params);
        if (child instanceof AbsListView) {
            directionalScrollListener = new DirectionalScrollListener(this, handlerScroll, timeShowOnStop);
            ((AbsListView) child).setOnScrollListener(directionalScrollListener);
        }
    }

    @Override
    protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
        super.onLayout(changed, left, top, right, bottom);

        marginRight = (int) (marginRight * density);
        marginBottom = (int) (marginBottom * density);

        if (floatView != null) {
            floatView.layout(right - marginRight - floatView.getMeasuredWidth(),
                    bottom - marginRight - floatView.getMeasuredHeight(),
                    right - marginRight,
                    bottom - marginRight);
        }
    }

    @Override
    public void onUpScrolling() {
        if (float_state == FLOAT_STATE.INVISIBLE) {
            getUpAnimation().start();
        }
    }

    @Override
    public void onDownScrolling() {
        if (float_state == FLOAT_STATE.VISIBLE) {
            getDownAnimation().start();
        }
    }

    @Override
    public void onScrollStop() {
        if (float_state == FLOAT_STATE.INVISIBLE) {
            getDownAnimation().cancel();
            getUpAnimation().start();
        }
    }

    private ObjectAnimator getUpAnimation() {
        if (upAnimation == null) {

            float initial = getBottom() + floatView.getMeasuredHeight() * fraction;
            float end = getBottom() - marginRight - floatView.getMeasuredHeight();

            PropertyValuesHolder pvhF = PropertyValuesHolder.ofFloat(Y, initial, end);

            upAnimation = ObjectAnimator.ofPropertyValuesHolder(floatView, pvhF);

            upAnimation.setDuration(600);
            upAnimation.setRepeatCount(0);
        }
        FloatAnimatorListener floatAnimatorListener = new FloatAnimatorListener(FLOAT_STATE.VISIBLE);

        upAnimation.addUpdateListener(floatAnimatorListener);
        upAnimation.addListener(floatAnimatorListener);

        return upAnimation;
    }

    private ObjectAnimator getDownAnimation() {
        if (downAnimation == null) {

            float initial = floatView.getY() * fraction;
            float end = getBottom() + floatView.getMeasuredHeight();

            PropertyValuesHolder pvhF = PropertyValuesHolder.ofFloat(Y, initial, end);

            downAnimation = ObjectAnimator.ofPropertyValuesHolder(floatView, pvhF);

            downAnimation.setDuration(600);
            downAnimation.setRepeatCount(0);
        }
        FloatAnimatorListener floatAnimatorListener = new FloatAnimatorListener(FLOAT_STATE.INVISIBLE);

        downAnimation.addUpdateListener(floatAnimatorListener);
        downAnimation.addListener(floatAnimatorListener);
        return downAnimation;
    }

    private enum FLOAT_STATE {
        VISIBLE,
        INVISIBLE,
        RUNING;
    }

    private class FloatAnimatorListener implements Animator.AnimatorListener, ValueAnimator.AnimatorUpdateListener {

        private FLOAT_STATE stateEnd;

        public FloatAnimatorListener(FLOAT_STATE stateEnd) {
            this.stateEnd = stateEnd;
        }

        @Override
        public void onAnimationStart(Animator animation) {
            float_state = FLOAT_STATE.RUNING;
        }

        @Override
        public void onAnimationEnd(Animator animation) {
            float_state = stateEnd;
        }

        @Override
        public void onAnimationCancel(Animator animation) {

        }

        @Override
        public void onAnimationRepeat(Animator animation) {

        }

        @Override
        public void onAnimationUpdate(ValueAnimator animation) {
            fraction = animation.getAnimatedFraction();
        }
    }

    public void setUpAnimation(ObjectAnimator upAnimation) {
        this.upAnimation = upAnimation;
    }

    public void setDownAnimation(ObjectAnimator downAnimation) {
        this.downAnimation = downAnimation;
    }

    public int getMarginRight() {
        return marginRight;
    }

    public void setMarginRight(int marginRight) {
        this.marginRight = marginRight;
    }

    public int getMarginBottom() {
        return marginBottom;
    }

    public void setMarginBottom(int marginBottom) {
        this.marginBottom = marginBottom;
    }

    public long getTimeShowOnStop() {
        return timeShowOnStop;
    }

    public void setTimeShowOnStop(long timeShowOnStop) {
        this.timeShowOnStop = timeShowOnStop;
        directionalScrollListener.setCountdownStop(timeShowOnStop);
    }

    public AbsListView.OnScrollListener getHandlerScroll() {
        return handlerScroll;
    }

    public void setHandlerScroll(AbsListView.OnScrollListener handerScroll) {
        this.handlerScroll = handerScroll;
        directionalScrollListener.setHandlerScroll(handlerScroll);
    }
}