RelativeLayout是的子类
View，以下内容适用于任何视图：
final View v; // The view that you want to save as an imageBitmap bitmap = Bitmap.createBitmap(v.getWidth(), v.getHeight(), Bitmap.Config.ARGB_8888);Canvas c = new Canvas(bitmap);v.draw(c);File outputFile; // Where to save itFileOutputStream out = new FileOutputStream(imageFile);boolean success = bitmap.compress(CompressFormat.PNG, 100, out);out.close();
随意添加异常处理。;）
