The above two lines is gray cause I under a lot of code is invalid, please have know why ah, I've just started, is not very good

CodePudding user response:

Has nothing to do with gray, gray, you have not the code references to these packages,
You need other package, you move the mouse you think invalid code, such as 0.5 seconds, you will see a yellow light, then choose "" "" the introduction of package, try a few more, general can solve,
If one didn't appear yellow light, show how the code you write (kao code on the net, need a lot of third-party packages, this is more than an introduction to a layer)