0.报错&提示信息:

'clickable' attribute found, please also add 'focusable'  A widget that is declared to be clickable but not declared to be focusable is not accessible via the keyboard. Please add the focusable attribute as well.

1.原因:

一个控件,如果没有定义focusable(可聚焦的),却定义了是clickable(可点击的),那么是不能通过键盘访问的。所以,需要添加一个focusable="true"。

2.解决方法:

切换到design试图,点击红框中的修复。如图: