R cannot be resolved to a variable without doing anything to the project

Question

I am getting the error "R cannot be resolved to a variable" that many people seems to be getting. However, none of the answers that I have seen has worked for me. I've gone to the extreme basic and created a helloworld project, with all default settings. The "R cannot be resolved to a variable" error is created instantly, and I cannot see what is wrong... no xml errors, all lowercase in /res/ folder, no difference in AndroidManifest.xml.

For reference, the code on MainActivity.java is:

package com.test.helloworld;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

}

Is there something wrong with eclipse setting? I'm using Windows 7 64-bit

PLease check whether there is some error in your xml files..Otherwise change your project target and revert back.. — Subburaj, Jun 20 '13 at 04:17
Is this something you are facing issue for? http://stackoverflow.com/questions/16642604/eclipse-error-r-cannot-be-resolved-to-a-variable/16643060#16643060 — Paresh Mayani, Jun 20 '13 at 04:18
when you import it ask you for import android.R or com.test.r ? anythis like this?? and check that in gen folder there must be r.java — PankajAndroid, Jun 20 '13 at 04:21
Deleted the projects bin and gen folder. then build the project. Resatrt the eclipse. — amalBit, Jun 20 '13 at 04:22
it must be error in your xml or your drawable folder images names convenstion could be wrong, please check it out, then clean the project . it will definetily run — abhi, Jun 20 '13 at 04:24
clean build mostly solves the problem.. also [check out this link](http://stackoverflow.com/a/7824975/2345913) — CRUSADER, Jun 20 '13 at 04:45
Double check that you installed the "Build tools" in the SDK manager. — dmon, Jun 20 '13 at 05:07

score 0 · Answer 1 · answered Jun 20 '13 at 04:28

Whenever I had a problem with R not been generated, or even disappeared, first clean and rebuild the project, if this is not worked then it was due to some problem in the XML layout file that prevented the application from being built. Check for the /res directory and there must be some file that have some error in it and that is preventing the application from being built. For example, it may be a layout file or it may be due to some missing resource is, but you already defined it in the XML file.

R cannot be resolved to a variable without doing anything to the project

1 Answers1