Gen folder is in project explorer but R file is not there.
it showing error on the (R.layou.main).

```
package org.example.Wardrobe;

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

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

```