Android中 Bitmap和Drawable相互转换的方法

1.Drawable—>Bitmap

Resources res=getResources();

Bitmap bmp=BitmapFactory.decodeResource(res, R.drawable.sample_0);
Resources res=getResources();
private byte[] Bitmap2Bytes(Bitmap bm){

2.Bitmap---->Drawable

Drawable drawable =new BitmapDrawable(bmp);

3、Drawable → Bitmap

public static Bitmap drawableToBitmap(Drawable drawable) {
        
         Bitmap bitmap = Bitmap.createBitmap(
                                         drawable.getIntrinsicWidth(),
                                         drawable.getIntrinsicHeight(),
                                         drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888
                                                         : Bitmap.Config.RGB_565);
         Canvas canvas = new Canvas(bitmap);
         //canvas.setBitmap(bitmap);
         drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
         drawable.draw(canvas);
         return bitmap;
 }

4、从资源中获取Bitmap

Bitmap bmp=BitmapFactory.decodeResource(res, R.drawable.pic);

5、Bitmap → byte[]

    ByteArrayOutputStream baos = new ByteArrayOutputStream();

    bm.compress(Bitmap.CompressFormat.PNG, 100, baos);

    return baos.toByteArray();   }

6、 byte[] → Bitmap

private Bitmap Bytes2Bimap(byte[] b){
                     if(b.length!=0){
                             return BitmapFactory.decodeByteArray(b, 0, b.length);
                     }
                     else {
                             return null;
                     }
           }