Android Dev - R.layout.main , Variable 'R' cannot be resolved

Question

We are new to Android and we are trying to develop a new application. We installed all the basic setup of Android. We tried to run the Android Sample projects in Eclipse. But while to compile the following lines and a few other lines that uses the variable 'R' throws up an error.

setContentView(R.layout.activity_main);

'R cannot be resolved to a variable'. I do not understand what is causing the error. Anyone help me out in this issue.

was your problem finally solve ? – Alireza Sanaee Sep 08 '13 at 06:43 — Alireza Sanaee, Sep 08 '13 at 06:43

score 7 · Answer 1 · answered Nov 16 '11 at 00:58

7

check that the import for R class is not

import com.android.R;

and you should make it

import yourpackagename.R;

then recompile

answered Nov 16 '11 at 00:58

confucius

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score 3 · Answer 2 · edited May 23 '17 at 12:10

3

Please try to clean the project, and try compiling again.

If not solved, refer to R cannot be resolved - Android error

edited May 23 '17 at 12:10

Community

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1

answered Nov 16 '11 at 00:58

Jason Kuang

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score 2 · Answer 3 · answered Mar 28 '13 at 16:20

2

If you have 64 bit Linux platform without ia32 libraries, then this problem could also occur. It took me quite some time to pin this one down, seeing that the problem is not clearly linked with the inability to execute 32 bit code.

answered Mar 28 '13 at 16:20

NTwoO

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6

score 1 · Answer 4 · edited Nov 16 '12 at 01:05

1

Just make the import part import com.android.R.layout instead of com.android.R

edited Nov 16 '12 at 01:05

Alex Wiese

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answered Nov 16 '12 at 00:42

Emre

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score 1 · Answer 5 · answered Aug 24 '13 at 05:43

1

In my case i forgot to re-install the SDK. When you re-install your operating system, you should re-extract (re-install) your SDK Zip file.

answered Aug 24 '13 at 05:43

score 0 · Answer 6 · answered Nov 05 '12 at 11:38

0

Check if your resorce name (for example template.xml) has ONLY small caps letters.

answered Nov 05 '12 at 11:38

baron_bartek

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score 0 · Answer 7 · answered May 16 '13 at 07:01

0

import com.packagename.R* will worl

answered May 16 '13 at 07:01

Dapper Dan

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score 0 · Answer 8 · edited Jan 17 '14 at 06:10

0

Change import to

import yourpackagename.R;

If error is still there then

go to gen folder->packagename->R.java

and remove error line some times it gave error on drawable files.

edited Jan 17 '14 at 06:10

Aniket Kulkarni

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answered Jan 17 '14 at 05:50

Umer

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score 0 · Answer 9 · answered Jun 23 '16 at 12:58

0

setContentView(R.layout.activity_main)

Change the SDK and delete the project and create new ... it will definitely work!

answered Jun 23 '16 at 12:58

SivaRamaKrishnan T

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1

score 0 · Answer 10 · answered Nov 16 '11 at 01:24

0

Also check that you have your android libraries mapped correctly in the settings for Eclipse (if you are using eclipse to develop).

answered Nov 16 '11 at 01:24

Bryan

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Android Dev - R.layout.main , Variable 'R' cannot be resolved

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