android在处理一写图片资源的时候，会进行一些类型的转换，现在有空整理一下：
1、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; }
2、从资源中获取Bitmap
Resources res=getResources(); Bitmap bmp=BitmapFactory.decodeResource(res, R.drawable.pic);
3、Bitmap → byte[]
private byte[] Bitmap2Bytes(Bitmap bm){ ByteArrayOutputStream baos = new ByteArrayOutputStream(); bm.compress(Bitmap.CompressFormat.PNG, 100, baos); return baos.toByteArray(); }
4、 byte[] → Bitmap
private Bitmap Bytes2Bimap(byte[] b){ if(b.length!=0){ return BitmapFactory.decodeByteArray(b, 0, b.length); } else { return null; }
} 5、Drawable → Bitmap Bitmap bmp1; Drawable dw1 = new BitmapDrawable(bmp1);