android图像绘制（五）——画布保存为图片

[java]

Bitmap bmp = Bitmap.createBitmap(480, 800, Config.ARGB_8888);

Canvas canvas = new Canvas(bmp);

canvas.drawBitmap(this.bmp, matrix, paint);

canvas.save(Canvas.ALL_SAVE_FLAG);

canvas.restore();

File file = new File("/sdcard/akai/");

if(!file.exists())

file.mkdirs();

try {

FileOutputStream fos = new FileOutputStream(file.getPath() + "/2.png");

bmp.compress(Bitmap.CompressFormat.PNG, 100, fos);

fos.close();

System.out.println("saveBmp is here");

} catch (Exception e) {

e.printStackTrace();

}

Bitmap bmp = Bitmap.createBitmap(480, 800, Config.ARGB_8888);

Canvas canvas = new Canvas(bmp);

canvas.drawBitmap(this.bmp, matrix, paint);

canvas.save(Canvas.ALL_SAVE_FLAG);

canvas.restore();

File file = new File("/sdcard/akai/");

if(!file.exists())

file.mkdirs();

try {

FileOutputStream fos = new FileOutputStream(file.getPath() + "/2.png");

bmp.compress(Bitmap.CompressFormat.PNG, 100, fos);

fos.close();

System.out.println("saveBmp is here");

} catch (Exception e) {

e.printStackTrace();

}解释：
1、首先创建一个Bitmap图片，并指定大小；

2、在该图片上创建一个新的画布Canvas，然后在画布上绘制，并保存即可；

3、需要保存的目录File，注意如果写的目录如“/sdcard/akai/”如果不存在的话，要先创建（file.mkdirs())，否则FileOutputStream会报错No found；

4、需要添加权限：<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>