Error in all the classes files: R cannot be resolved

Question

Example code:

setContentView(R.layout.main);

Error:

R cannot be resolved

There's this error in all the classes files, and I can't get rid of it.

I already checked the XML files, there are no errors.

I already made sure that I didn't accidentally import "android.R".

The problem started when I tried to Clean and Rebuild the project.

@edoardotognoni yes I did. I updated it yesterday, but it worked after I updated it just started today... — Eli Revah, May 17 '13 at 08:19
Is there an import R in your files? If so remove that import from all files — Tim, May 17 '13 at 08:20
@EliRevah you can try the accepted answer in the link. Not sure if it helps. but give it a try. — Raghunandan, May 17 '13 at 08:33
Try to Clean if not generated then restart eclipse..bcoz i face d same problem also. — Sam, May 17 '13 at 08:38

score 1 · Accepted Answer · answered May 17 '13 at 08:25

1

If you already updated the SDK tools, re-open the SDK manager and check under the "Tools" section that "Android SDK Build tools" are installed and eventually, update them. That made the trick for me yesterday.

answered May 17 '13 at 08:25

edoardotognoni

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score 0 · Answer 2 · answered May 17 '13 at 08:18

Check if your R is generated properly inside the "gen" folder.Check if there are any libraries missing which are added as dependencies from project properties. Also make sure that there are no issues which is preventing the app from generating R file. Go to Window > Show view> Problems and it will show you whats missing.

score 0 · Answer 3 · answered May 17 '13 at 08:21

0

1) Delete your Gen folder (It will be automatically created afterwards).

2) Clean you project.

See the miracle. :)

answered May 17 '13 at 08:21

Varun Vishnoi

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Now I did what you told me, and the Gen folder isn't being created again. – Eli Revah May 17 '13 at 08:31

score 0 · Answer 4 · answered May 17 '13 at 08:22

0

Please do the following:

1.Check whether there are errors in your xml file.

2.Try to clean the project and run it.

answered May 17 '13 at 08:22

Subburaj

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I already checked for errors in the XML files, and cleaning the project is what ruined it in the first place. – Eli Revah May 17 '13 at 08:28

Jarvis · Answer 5 · 2013-05-17T08:41:36.717

0

Yesterday, I made an update with sdk manager, and I had the same problem as you. I fixed the issue: I have updated another time the android sdk (with the sdk manager tool), then I check update from eclipse for install the updated ADT plugin and I rebuid my project. "Android sdk Build-tools" from Android sdk manager is now rev 17 and now it is OK. I think the issue is from adt plugin from eclipse

edited May 17 '13 at 08:41

answered May 17 '13 at 08:35

Jarvis

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Error in all the classes files: R cannot be resolved

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