Android创建原图的副本

package com.itheima74.copybitmap;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Matrix;import android.graphics.Paint;import android.os.Bundle;import android.support.v7.app.AppCompatActivity;import android.widget.ImageView;/** * 创建原图的副本 */public class MainActivity extends AppCompatActivity {    @Override    PRotected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        ImageView iv_src = (ImageView) findViewById(R.id.iv_src);        ImageView iv_copy = (ImageView) findViewById(R.id.iv_copy);        Bitmap bitmap_src = BitmapFactory.decodeResource(getResources(), R.drawable.tomcat);        iv_src.setImageBitmap(bitmap_src);        // 操作原图,报错,不可以直接操作原图        // bitmap_src.setPixel(50,50, Color.RED);        // 创建一个原图的副本        Bitmap bitmap_copy = Bitmap.createBitmap(bitmap_src.getWidth(), bitmap_src.getHeight(),                bitmap_src.getConfig());// 配置副本参数        Paint paint = new Paint();// 画笔        Canvas canvas = new Canvas(bitmap_copy);// 画布        // 开始作画,参考原图,此行代码执行完毕bitmap_copy有内容        canvas.drawBitmap(bitmap_src, new Matrix(), paint);        // 操作副本        for (int i = 0; i < 50; i++) {            bitmap_copy.setPixel(50 + i, 50, Color.RED);        }        iv_copy.setImageBitmap(bitmap_copy);    }}