<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
 <item
  android:drawable="@drawable/eel_mask1"/>
 <item
  android:drawable="@drawable/eel_mask2"/>
 <item
  android:drawable="@drawable/eel_mask3"/>
 <item
  android:drawable="@drawable/eel_mask4"/>
 <item
  android:drawable="@drawable/eel_mask5"/>
 <item
  android:drawable="@drawable/eel_mask6"/>
 <item
  android:drawable="@drawable/eel_mask7"/>
</layer-list>

package com.zhy.colour_app_01;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Color;
import android.graphics.PorterDuff;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.graphics.drawable.LayerDrawable;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;

import java.util.Random;

/**
 * Created by zhy on 15/5/14.
 */
public class ColourImageBaseLayerView extends View
{

 private LayerDrawable mDrawables;

 public ColourImageBaseLayerView(Context context, AttributeSet attrs)
 {
  super(context, attrs);
  mDrawables = (LayerDrawable) getBackground();

 }

 @Override
 protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec)
 {
  setMeasuredDimension(mDrawables.getIntrinsicWidth(), mDrawables.getIntrinsicHeight());
 }

 @Override
 public boolean onTouchEvent(MotionEvent event)
 {
  final float x = event.getX();
  final float y = event.getY();
  if (event.getAction() == MotionEvent.ACTION_DOWN)
  {
   Drawable drawable = findDrawable(x, y);
   if (drawable != null)
    drawable.setColorFilter(randomColor(), PorterDuff.Mode.SRC_IN);
  }

  return super.onTouchEvent(event);
 }

 private int randomColor()
 {
  Random random = new Random();
  int color = Color.argb(255, random.nextInt(256), random.nextInt(256), random.nextInt(256));
  return color;
 }

 private Drawable findDrawable(float x, float y)
 {
  final int numberOfLayers = mDrawables.getNumberOfLayers();
  Drawable drawable = null;
  Bitmap bitmap = null;
  for (int i = numberOfLayers - 1; i >= 0; i--)
  {
   drawable = mDrawables.getDrawable(i);
   bitmap = ((BitmapDrawable) drawable).getBitmap();
   try
   {
    int pixel = bitmap.getPixel((int) x, (int) y);
    if (pixel == Color.TRANSPARENT)
    {
     continue;
    }
   } catch (Exception e)
   {
    continue;
   }
   return drawable;
  }
  return null;
 }

}

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin"
    tools:context=".MainActivity">

 <com.zhy.colour_app_01.ColourImageBaseLayerView
  android:background="@drawable/eel"
  android:layout_width="match_parent"
  android:layout_centerInParent="true"
  android:layout_height="match_parent"/>

</RelativeLayout>

/**
  * @param pixels 像素数组
  * @param w  宽度
  * @param h  高度
  * @param pixel 当前点的颜色
  * @param newColor 填充色
  * @param i  横坐标
  * @param j  纵坐标
  */
 private void fillColor01(int[] pixels, int w, int h, int pixel, int newColor, int i, int j)
 {
  int index = j * w + i;
  if (pixels[index] != pixel || i >= w || i < 0 || j < 0 || j >= h)
   return;
  pixels[index] = newColor;
  //上
  fillColor01(pixels, w, h, pixel, newColor, i, j - 1);
  //右
  fillColor01(pixels, w, h, pixel, newColor, i + 1, j);
  //下
  fillColor01(pixels, w, h, pixel, newColor, i, j + 1);
  //左
  fillColor01(pixels, w, h, pixel, newColor, i - 1, j);
 }

/**
  * @param pixels 像素数组
  * @param w  宽度
  * @param h  高度
  * @param pixel 当前点的颜色
  * @param newColor 填充色
  * @param i  横坐标
  * @param j  纵坐标
  */
 private void fillColor(int[] pixels, int w, int h, int pixel, int newColor, int i, int j)
 {
  mStacks.push(new Point(i, j));

  while (!mStacks.isEmpty())
  {
   Point seed = mStacks.pop();
   Log.e("TAG", "seed = " + seed.x + " , seed = " + seed.y);

   int index = seed.y * w + seed.x;

   pixels[index] = newColor;
   if (seed.y > 0)
   {
    int top = index - w;
    if (pixels[top] == pixel)
    {

     mStacks.push(new Point(seed.x, seed.y - 1));
    }
   }

   if (seed.y < h - 1)
   {
    int bottom = index + w;
    if (pixels[bottom] == pixel)
    {
     mStacks.push(new Point(seed.x, seed.y + 1));
    }
   }

   if (seed.x > 0)
   {
    int left = index - 1;
    if (pixels[left] == pixel)
    {
     mStacks.push(new Point(seed.x - 1, seed.y));
    }
   }

   if (seed.x < w - 1)
   {
    int right = index + 1;
    if (pixels[right] == pixel)
    {
     mStacks.push(new Point(seed.x + 1, seed.y));
    }
   }

  }


 }

public class ColourImageView extends ImageView
{

 private Bitmap mBitmap;
 /**
  * 边界的颜色
  */
 private int mBorderColor = -1;

 private boolean hasBorderColor = false;

 private Stack<Point> mStacks = new Stack<Point>();

 public ColourImageView(Context context, AttributeSet attrs)
 {
  super(context, attrs);

  TypedArray ta = context.obtainStyledAttributes(attrs, R.styleable.ColourImageView);
  mBorderColor = ta.getColor(R.styleable.ColourImageView_border_color, -1);
  hasBorderColor = (mBorderColor != -1);

  L.e("hasBorderColor = " + hasBorderColor + " , mBorderColor = " + mBorderColor);

  ta.recycle();

 }

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

  int viewWidth = getMeasuredWidth();
  int viewHeight = getMeasuredHeight();

  //以宽度为标准，等比例缩放view的高度
  setMeasuredDimension(viewWidth,
    getDrawable().getIntrinsicHeight() * viewWidth / getDrawable().getIntrinsicWidth());
  L.e("view's width = " + getMeasuredWidth() + " , view's height = " + getMeasuredHeight());

  //根据drawable，去得到一个和view一样大小的bitmap
  BitmapDrawable drawable = (BitmapDrawable) getDrawable();
  Bitmap bm = drawable.getBitmap();
  mBitmap = Bitmap.createScaledBitmap(bm, getMeasuredWidth(), getMeasuredHeight(), false);
 }

@Override
 public boolean onTouchEvent(MotionEvent event)
 {
  final int x = (int) event.getX();
  final int y = (int) event.getY();
  if (event.getAction() == MotionEvent.ACTION_DOWN)
  {
   //填色
   fillColorToSameArea(x, y);
  }

  return super.onTouchEvent(event);
 }

 /**
  * 根据x,y获得改点颜色，进行填充
  *
  * @param x
  * @param y
  */
 private void fillColorToSameArea(int x, int y)
 {
  Bitmap bm = mBitmap;

  int pixel = bm.getPixel(x, y);
  if (pixel == Color.TRANSPARENT || (hasBorderColor && mBorderColor == pixel))
  {
   return;
  }
  int newColor = randomColor();

  int w = bm.getWidth();
  int h = bm.getHeight();
  //拿到该bitmap的颜色数组
  int[] pixels = new int[w * h];
  bm.getPixels(pixels, 0, w, 0, 0, w, h);
  //填色
  fillColor(pixels, w, h, pixel, newColor, x, y);
  //重新设置bitmap
  bm.setPixels(pixels, 0, w, 0, 0, w, h);
  setImageDrawable(new BitmapDrawable(bm));

 }

/**
  * @param pixels 像素数组
  * @param w  宽度
  * @param h  高度
  * @param pixel 当前点的颜色
  * @param newColor 填充色
  * @param i  横坐标
  * @param j  纵坐标
  */
 private void fillColor(int[] pixels, int w, int h, int pixel, int newColor, int i, int j)
 {
  //步骤1：将种子点(x, y)入栈；
  mStacks.push(new Point(i, j));

  //步骤2：判断栈是否为空，
  // 如果栈为空则结束算法，否则取出栈顶元素作为当前扫描线的种子点(x, y)，
  // y是当前的扫描线；
  while (!mStacks.isEmpty())
  {


   /**
    * 步骤3：从种子点(x, y)出发，沿当前扫描线向左、右两个方向填充，
    * 直到边界。分别标记区段的左、右端点坐标为xLeft和xRight；
    */
   Point seed = mStacks.pop();
   //L.e("seed = " + seed.x + " , seed = " + seed.y);
   int count = fillLineLeft(pixels, pixel, w, h, newColor, seed.x, seed.y);
   int left = seed.x - count + 1;
   count = fillLineRight(pixels, pixel, w, h, newColor, seed.x + 1, seed.y);
   int right = seed.x + count;


   /**
    * 步骤4：
    * 分别检查与当前扫描线相邻的y - 1和y + 1两条扫描线在区间[xLeft, xRight]中的像素，
    * 从xRight开始向xLeft方向搜索，假设扫描的区间为AAABAAC（A为种子点颜色），
    * 那么将B和C前面的A作为种子点压入栈中，然后返回第（2）步；
    */
   //从y-1找种子
   if (seed.y - 1 >= 0)
    findSeedInNewLine(pixels, pixel, w, h, seed.y - 1, left, right);
   //从y+1找种子
   if (seed.y + 1 < h)
    findSeedInNewLine(pixels, pixel, w, h, seed.y + 1, left, right);
  }


 }

 /**
  * 在新行找种子节点
  *
  * @param pixels
  * @param pixel
  * @param w
  * @param h
  * @param i
  * @param left
  * @param right
  */
 private void findSeedInNewLine(int[] pixels, int pixel, int w, int h, int i, int left, int right)
 {
  /**
   * 获得该行的开始索引
   */
  int begin = i * w + left;
  /**
   * 获得该行的结束索引
   */
  int end = i * w + right;

  boolean hasSeed = false;

  int rx = -1, ry = -1;

  ry = i;

  /**
   * 从end到begin，找到种子节点入栈（AAABAAAB，则B前的A为种子节点）
   */
  while (end >= begin)
  {
   if (pixels[end] == pixel)
   {
    if (!hasSeed)
    {
     rx = end % w;
     mStacks.push(new Point(rx, ry));
     hasSeed = true;
    }
   } else
   {
    hasSeed = false;
   }
   end--;
  }
 }

 /**
  * 往右填色，返回填充的个数
  *
  * @return
  */
 private int fillLineRight(int[] pixels, int pixel, int w, int h, int newColor, int x, int y)
 {
  int count = 0;

  while (x < w)
  {
   //拿到索引
   int index = y * w + x;
   if (needFillPixel(pixels, pixel, index))
   {
    pixels[index] = newColor;
    count++;
    x++;
   } else
   {
    break;
   }

  }

  return count;
 }


 /**
  * 往左填色，返回填色的数量值
  *
  * @return
  */
 private int fillLineLeft(int[] pixels, int pixel, int w, int h, int newColor, int x, int y)
 {
  int count = 0;
  while (x >= 0)
  {
   //计算出索引
   int index = y * w + x;

   if (needFillPixel(pixels, pixel, index))
   {
    pixels[index] = newColor;
    count++;
    x--;
   } else
   {
    break;
   }

  }
  return count;
 }

 private boolean needFillPixel(int[] pixels, int pixel, int index)
 {
  if (hasBorderColor)
  {
   return pixels[index] != mBorderColor;
  } else
  {
   return pixels[index] == pixel;
  }
 }

 /**
  * 返回一个随机颜色
  *
  * @return
  */
 private int randomColor()
 {
  Random random = new Random();
  int color = Color.argb(255, random.nextInt(256), random.nextInt(256), random.nextInt(256));
  return color;
 }

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:zhy="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin"
    tools:context=".MainActivity">
 <com.zhy.colour_app_01.ColourImageView
  zhy:border_color="#FF000000"
  android:src="@drawable/image_007"
  android:background="#33ff0000"
  android:layout_width="match_parent"
  android:layout_centerInParent="true"
  android:layout_height="match_parent"/>

</RelativeLayout>


<?xml version="1.0" encoding="utf-8"?>
<resources>
 <declare-styleable name="ColourImageView">
  <attr name="border_color" format="color|reference"></attr>
 </declare-styleable>
</resources>