Android Studio showing error in background monitoring code

when I used the code in Developer Docs for Background monitoring l got this errors and i do not know how to fix them.

do you have any idea about how to solve it ?

It only underlines notification. There is no actual error message on the screen. If you hover the mouse over that underlined text it should show a tool-tip telling you what is wrong. Then you can make a screen-shot.
This could be wrong imports, wrong Android target version, maybe it is a gradle error and a clean build will fix it.

I solved it !
I was create a class and gave it a name “notification” because that it could not reach the desired class, always reach my class .
when i tried to rename my class , it worked !!