我想通了。为了显示你在布局目录的src / main / RES /布局，打开该文件的丰富的布局工具。对我来说，这个文件是login.xml。

I figured it out. To show the rich layout tool you have to open the file in the layout directory, "src/main/res/layout". For me this file is, "login.xml".

另外请注意，在屏幕的底部有两个标签，设计和文本。

Also, note that at the bottom of the screen are two tabs, "Design" and "Text".