更新

如果您遇到与Android Studio 3.5相同的问题，请检查以下文章

if you facing same issue with Android Studio 3.5 please check below article

Android Studio 3.5升级XML重新格式化问题

打开File > Settings > Editor > Code Style > XML

现在在布局文件中，请确保已将包装属性选择为始终包装

Now in layout file make sure you have selected wrap attributes as Wrap always

就像下面的屏幕截图一样:

Like below screenshot: