Ripples using Probe and RevealColorViews

## RevealInterceptor.java
package com.cafesalam.experiments.app.ui;

import org.lucasr.probe.Interceptor;

import android.content.Context;
import android.graphics.Color;
import android.graphics.Point;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewParent;
import android.widget.FrameLayout;

import java.util.WeakHashMap;

import at.markushi.ui.RevealColorView;

/* this class is a Probe Interceptor that gives views a ripple effect
 * using https://github.com/markushi/android-ui.
 *
 * based on markus's sample gist:
 * https://gist.github.com/markushi/68ce8df77bed164b6275
 */
public class RevealInterceptor extends Interceptor {
  private static final int BACKGROUND = Color.parseColor("#212121");

  private Context mContext;
  private WeakHashMap<View, FrameLayout> mMapping;

  public RevealInterceptor(Context context) {
    mContext = context;
    mMapping = new WeakHashMap<>();
  }

  @Override
  public void onLayout(View view, boolean changed,
      int left, int top, int right, int bottom) {
    if (!(view instanceof ViewGroup)) {
      FrameLayout container = mMapping.get(view);
      if (container == null) {
        container = new FrameLayout(mContext);
        mMapping.put(view, container);
        RevealColorView revealColorView = new RevealColorView(mContext);
        revealColorView.setBackgroundColor(BACKGROUND);

        final ViewParent parent = view.getParent();
        if (parent instanceof ViewGroup) {
          final ViewGroup pvg = (ViewGroup) parent;
          final int index = pvg.indexOfChild(view);
          pvg.removeViewInLayout(view);

          // you'd perhaps set this in xml as per android-ui's gist
          view.setTag(new Holder("#8bc34a"));

          container.addView(revealColorView);
          container.addView(view);

          // ideally should use addViewInLayout, but can't because
          // it is protected
          pvg.addView(container, index, view.getLayoutParams());
          pvg.invalidate();
          view.setOnClickListener(mOnClickListener);
        }
      }
    }
    super.onLayout(view, changed, left, top, right, bottom);
  }

  private static class Holder {
    public int color;
    public boolean isShowing;

    public Holder(String colorStr) {
      this.color = Color.parseColor(colorStr);
    }
  }

  private View.OnClickListener mOnClickListener = new View.OnClickListener() {
    @Override
    public void onClick(View v) {
      final RevealColorView revealColorView =
          (RevealColorView) (((ViewGroup) v.getParent()).getChildAt(0));
      final Point p = getLocationInView(revealColorView, v);

      final Holder holder = (Holder) v.getTag();
      final int color = holder.color;

      if (holder.isShowing) {
        revealColorView.hide(p.x, p.y, BACKGROUND, 0, 300, null);
        holder.isShowing = false;
      } else {
        revealColorView.reveal(p.x, p.y, color, v.getHeight() / 2, 340, null);
        holder.isShowing = true;
      }
    }
  };

  private Point getLocationInView(View src, View target) {
    final int[] l0 = new int[2];
    src.getLocationOnScreen(l0);

    final int[] l1 = new int[2];
    target.getLocationOnScreen(l1);

    l1[0] = l1[0] - l0[0] + target.getWidth() / 2;
    l1[1] = l1[1] - l0[1] + target.getHeight() / 2;

    return new Point(l1[0], l1[1]);
  }
}