BitMap 和 Drawable 互相轉換

android開發過成中時而需要BitMap 和Drable之間的轉換：

 1. 網絡下載下傳圖檔轉換為Drawable代碼片段:

URL urlimage = new URL(imagepath);
  URLConnection mConnection= urlimage.openConnection();  
  mConnection.connect();  //獲得連接配接
  InputStream in=mConnection.getInputStream();
  BitMap bitmap=BitmapFactory.decodeStream(in);
  Drawable drawable = new BitmapDrawable(bitmap);
           

2.Drawable 轉化為 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);
	    drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
	    drawable.draw(canvas);
	    return bitmap;
	}