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Android

Posted by Matt Kimball
Matt Kimball
139 Points

Help with SetContentView() R cannot be resolved to variable

I could really use some help, I can't find a solution anywhere on the internet for my problem, I've been working on a project and when I loaded it today for each of the activities I have SetContentView(R.layout.mainScreen); The R is underlined in red and it says "R cannot be resolved to variable" What can I do to fix this? I would appreciate some help so much! Thank you

1 Answer

Ben Jakuben
STAFF
Ben Jakuben
Treehouse Teacher
Ben Jakuben
Ben Jakuben
Treehouse Teacher

Hi Matt, files in the res directory (where the R class gets generated from) cannot have uppercase letters. Change your layout filename to main_screen and you should fix these errors. This is a weird rule that I think every Android developer runs into when first starting!