New Android does not have r files and Settings auto Import Package

Today, there are some small problems, record, later convenient memory it.

Before also good project, disappear the Kungfu out an error "can not reslove symbol ' R '",

And there is no R folder under the App/build/generated/source directory,

In fact, without the error, only run a bit, automatically will be born R file

There is another question to add,

Just start the import package does not go in, who knows, can directly set the automatic import package, right here ~ ~, in the file of the Stetings

New Android does not have r files and Settings auto Import Package