图片 从三个地方读

//1，已将图片保存到drawable目录下

//通过图片id获得Drawable
Resource res=gerResource();

Drawable drawable=res.getDrawable(id);//id为R.drawable.图片名称

//通过图片id获得Bitmap

Resource res=gerResource();

Bitmap bitmap=BitmapFactory.decodeResource(res, id);

//若只知道图片的名称，可以通过图片的名称获得图片的id

//name:图片的名称 defType：图片的类型（png,jpeg),defPackage:工程的包名


int id =int id =res.getIdentifier(name, defType, defPackage);


//获得id之后可以根据你的需要来获得Bitmap或Drawable


//2,已将图片保存到assest目录下


//知道图片的名称，通过inputstream打开图片


AssetManager asm=getAssetMg();


InputStream is=asm.open(name);//name:图片的名称


//获得Drawable


Drawable da = Drawable.createFromStream(is, null);


//获得Bitmap


Bitmap bitmap=BitmapFactory.decodeStream(is);


//3,图片保存在sdcard,已知图片的路径

//图片路径


String path = Environment.getExternalStorageDirectory().toString()+ "/DCIM/device.png";


RandomAccessFile mMiniThumbFile；


File imgfile = new File(path);


try {


    mMiniThumbFile = new RandomAccessFile(imgfile, "rw");


} catch (IOException ex) {



// Open as read-only so we can at least read the existing



// thumbnails.


try {


mMiniThumbFile = new RandomAccessFile(imgfile, "r");


} catch (IOException ex2) {


// ignore exception

System.out.println(ex2.toString());


}



}

data= new byte[10553];

try {


mMiniThumbFile.seek(0);


int got = mMiniThumbFile.read(data, 0, 10552);

System.out.println("got="+got);


} catch (IOException e) {



// TODO Auto-generated catch block


e.printStackTrace();


System.out.println(e.toString());



}



if (data != null) {



//通过data获得bitmap


Bitmap bitmap = BitmapFactory.decodeByteArray(data, 0,data.length);