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Android

Posted by Holly Fox
Holly Fox
2,808 Points

Cannot resolve symbol R when hooking up the layout files

This has been a problem before but it resolved itself without me understanding what the problem was.

I have wrote my java code which has been running fine. I've now been making amendments to the layout file. I have only changed positioning of elements and haven't made any changes to ID's etc.

But now, for no particular reason, I have an error in my java code saying cannot resolve R for the following code: 

setContentView(R.layout.activity_colour_mix);

I've tried rebuilding and cleaning but it won't let me. I've tried ctrl + space after setContentView to force an import but thats not working either.

Any ideas?

1 Answer

Holly Fox
Holly Fox
2,808 Points
Holly Fox
Holly Fox
2,808 Points

The problem has resolved!

This time it was a problem in my layout file. I had 3 elements; I aligned the middle element with the center of the screen and aligned the other 2 above and below. Although there weren't any errors showing, as soon as I adjusted the code for the way this was aligned (aligning now based on the parent), android allowed me to clean and rebuild and the errors went away.

Its a bit frustrating that the layout file didn't show the source of the error but it does seem to be the problem.