将一个图片切割成多个图片

有种场景，我们想将一个图片切割成多个图片。比如我们在开发一个拼图的游戏，就首先要对图片进行切割。
以下是封装好的两个类，可以实现图片的切割。仅供参考和学习。
一个是ImagePiece类，此类保存了一个Bitmap对象和一个标识图片的顺序索引的int变量。
[java] import android.graphics.Bitmap;
public class ImagePiece {
    public int index = 0;
    public Bitmap bitmap = null;
}
import android.graphics.Bitmap;
public class ImagePiece {
    public int index = 0;
    public Bitmap bitmap = null;
}

一个是ImageSplitter类，有一个静态方法split，传入的参数是要切割的Bitmap对象，和横向和竖向的切割片数。比如传入的是3、3，则横竖向都切割成3片，最终会将整个图片切割成3X3=9片。
[java] import java.util.ArrayList;
import java.util.List;

import android.graphics.Bitmap;

public class ImageSplitter {

    public static List<ImagePiece> split(Bitmap bitmap, int xPiece, int yPiece) {

        List<ImagePiece> pieces = new ArrayList<ImagePiece>(xPiece * yPiece);
        int width = bitmap.getWidth();
        int height = bitmap.getHeight();
        int pieceWidth = width / 3;
        int pieceHeight = height / 3;
        for (int i = 0; i < yPiece; i++) {
            for (int j = 0; j < xPiece; j++) {
                ImagePiece piece = new ImagePiece();
                piece.index = j + i * xPiece;
                int xValue = j * pieceWidth;
                int yValue = i * pieceHeight;
                piece.bitmap = Bitmap.createBitmap(bitmap, xValue, yValue,
                        pieceWidth, pieceHeight);
                pieces.add(piece);
            }
        }

        return pieces;
    }

}
import java.util.ArrayList;
import java.util.List;

import android.graphics.Bitmap;

public class ImageSplitter {

    public static List<ImagePiece> split(Bitmap bitmap, int xPiece, int yPiece) {

        List<ImagePiece> pieces = new ArrayList<ImagePiece>(xPiece * yPiece);
        int width = bitmap.getWidth();
        int height = bitmap.getHeight();
        int pieceWidth = width / 3;
        int pieceHeight = height / 3;
        for (int i = 0; i < yPiece; i++) {
            for (int j = 0; j < xPiece; j++) {
                ImagePiece piece = new ImagePiece();
                piece.index = j + i * xPiece;
                int xValue = j * pieceWidth;
                int yValue = i * pieceHeight;
                piece.bitmap = Bitmap.createBitmap(bitmap, xValue, yValue,
                        pieceWidth, pieceHeight);
                pieces.add(piece);
            }
        }

        return pieces;
    }

}

1、图标加灰色过滤；
2、android的图片资源默认是静态的，单实例；如果两个IM好友的头像一样，最简单的都是用的软件自带头像，有一个在线，一个离线，直接改变头像的灰度，则两个用户的头像都会变灰或者在线，答案是：Drawable.mutate()。
[java] Drawable mDrawable = context.getResources().getDrawable(R.drawable.face_icon);
//Make this drawable mutable.
//A mutable drawable is guaranteed to not share its state with any other drawable.
mDrawable.mutate();
ColorMatrix cm = new ColorMatrix();
cm.setSaturation(0);
ColorMatrixColorFilter cf = new ColorMatrixColorFilter(cm);
mDrawable.setColorFilter(cf);
Drawable mDrawable = context.getResources().getDrawable(R.drawable.face_icon);
//Make this drawable mutable.
//A mutable drawable is guaranteed to not share its state with any other drawable.
mDrawable.mutate();
ColorMatrix cm = new ColorMatrix();
cm.setSaturation(0);
ColorMatrixColorFilter cf = new ColorMatrixColorFilter(cm);
mDrawable.setColorFilter(cf);

生成缩略图，抠自android launcher源码：
[java] /*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
&n

补充：移动开发 , Android ,