R cannot be resolved

package com.ustr.eMIRnew;

import java.util.ArrayList;
import java.util.HashMap;
import android.R;
import android.app.Activity;
import android.os.Bundle;
import android.widget.ListView;
import android.widget.SimpleAdapter;

public class eMIRnew extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }
}`

This is my code. But it is sho开发者_JAVA百科wing the error R cannot be resolved.

I have tried many methods like clean-and-build, closed-and-open the project, changed import android.R to import your.package.name.R etc. But nothing helped. Can anybody help me, please?

You are Importing android.R package, which is default one provided by Android. If you want to access your own Layout, assets, String. . . then Remove the import android.R statement.

No need to import your Package.R, By default, R file is generated during built.

You are using the android R file you have to use you package R file if you want to access the main layout for you app. import you_package.R

Remove the import statement:

import android.R;

In the onCreate method where you set the content view to R.layout.main, your project should be using this file:

com.ustr.eMIRnew.R

This file is generated when you build your project. Are you using Eclipse for building? Then this should not be a problem.