第一个Android应用程序（32/64位问题？）

Question

I am trying to build the "hello world" example on Eclipse (tried NetBeans as well). The code is very simple:

package com.example.myfirstapp;


import android.app.Activity;
import android.os.Bundle;
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;
    }

}

I get 2 "R cannot be resolved to a variable" errors.

As this seems to be a known issue, I already tried all the solutions regarding import, clean, restarting Eclipse, checking the manifest, etc

A few of the answers, however, talk about some issue with missing 32-bit libraries on 64-bit systems (I use 64b Windows 7). I also noticed that Eclipse does not flag errors in ANY other folders. Also, that my project gen folder is empty.

Since the code is very simple, I am pretty sure the problem is elsewhere. Unfortunately, I do not know enough about Java, Eclipse or Netbeans to fix it.

I would appreciate any help.

Answer 1

You are missing the java import needed to resolve to the activity_main.xml, so add

import com.example.myfirstapp.R;
(this should be whatever your app package is your androidmanifest and then ".R")

under your package line ( package com.example.myfirstapp; )

You IDE should stop complaining