Android通過url獲取bitmap圖片問題

//定義一個根據圖片url獲取InputStream的方法
    public static byte[] getBytes(InputStream is) throws IOException {
        ByteArrayOutputStream outstream = new ByteArrayOutputStream();
        byte[] buffer = new byte[1024]; // 用數據裝
        int len = -1;
        while ((len = is.read(buffer)) != -1) {
            outstream.write(buffer, 0, len);
        }
        outstream.close();
        // 關閉流一定要記得。
        return outstream.toByteArray();
    }

//然後使用方法decodeByteArray（）方法解析編碼，生成Bitmap對象。
    byte[] data = getBytes(new URL(imgUrl).openStream());
    Bitmap bm = BitmapFactory.decodeByteArray(data, 0, data.length);

以下是一個設置壁紙的實例應用

	new Thread(){
				@Override
				public void run(){
					//你要執行的方法
					try {
						byte[] data = getBytes(new URL(picurl).openStream());  
						bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);
						WallpaperManager wallpaperManager = WallpaperManager.getInstance(getApplicationContext());
						wallpaperManager.setBitmap(bitmap);
					}
					catch (Exception e) {
						Toast.makeText(DialogPhotoEntry.this,"設置桌面圖片失敗", 1000).show();
						e.printStackTrace();
					}
					//執行完畢後給handler發送一個空消息
					handler.sendEmptyMessage(0);
				}
			}.start();