title: NullPointerException when adding an object to ArrayList in Android
body: <p>I'm trying to create a List View with BaseAdapter and i keep getting a Null Object Reference Error at the point of adding an object to an ArrayList.</p>
  
  <p>Relevant code is below:</p>
  
  <pre><code>public class MainActivity extends ActionBarActivity {
      int[] icons = {R.drawable.icon01, R.drawable.icon02, R.drawable.icon03, R.drawable.icon04, R.drawable.icon05, R.drawable.icon06, R.drawable.icon07, R.drawable.icon08, R.drawable.icon09, R.drawable.icon10, R.drawable.icon11, R.drawable.icon12};
      ListView listView;
      String[] title, desc;
  
      @Override
      protected void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.activity_main);
  
          listView = (ListView) findViewById(R.id.listView);
  
          Resources resources = getResources();
          title = resources.getStringArray(R.array.titles);
          desc = resources.getStringArray(R.array.desc);
  
          RT_Adapter rt_adapter = new RT_Adapter(this, title, desc, icons);
          listView.setAdapter(rt_adapter);
      }
  }
  
  class Creator {
      String a, b;
      int c;
  
      Creator(String d, String e, int f) {
          this.a = d;
          this.b = e;
          this.c = f;
          Log.d("RT", a +" - "+b+" - "+c); //Position 01 - This is Description 01 - 2130837556
      }
  }
  
  class RT_Adapter extends BaseAdapter {
      Context c;
      ArrayList&lt;Creator&gt; list;
  
      public RT_Adapter(Context context, String[] title, String[] descs, int[] icons) {
          this.c = context;
          for (int i = 0; i &lt; title.length; i++) {
              list.add(new Creator(title[i], descs[i], icons[i]));
          }
      }
  
      ...
  }
  </code></pre>
  
  <p>I get the error at the below line(found out while debugging):</p>
  
  <pre><code>list.add(new Creator(title[i], descs[i], icons[i]));
  </code></pre>
  
  <p>Below is the actual Error in Logcat:</p>
  
  <pre><code>02-09 17:09:05.494      767-767/? E/AndroidRuntime﹕ FATAL EXCEPTION: main
      Process: com.rt.droid.baseadapter01, PID: 767
      java.lang.RuntimeException: Unable to start activity ComponentInfo{com.rt.droid.baseadapter01/com.rt.droid.baseadapter01.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'boolean java.util.ArrayList.add(java.lang.Object)' on a null object reference
              at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2298)
              at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
              at android.app.ActivityThread.access$800(ActivityThread.java:144)
              at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
              at android.os.Handler.dispatchMessage(Handler.java:102)
              at android.os.Looper.loop(Looper.java:135)
              at android.app.ActivityThread.main(ActivityThread.java:5221)
              at java.lang.reflect.Method.invoke(Native Method)
              at java.lang.reflect.Method.invoke(Method.java:372)
              at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:898)
              at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:693)
       Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'boolean java.util.ArrayList.add(java.lang.Object)' on a null object reference
              at com.rt.droid.baseadapter01.RT_Adapter.&lt;init&gt;(MainActivity.java:71)
              at com.rt.droid.baseadapter01.MainActivity.onCreate(MainActivity.java:36)
              at android.app.Activity.performCreate(Activity.java:5933)
              at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105)
              at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2251)
              at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
              at android.app.ActivityThread.access$800(ActivityThread.java:144)
              at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
              at android.os.Handler.dispatchMessage(Handler.java:102)
              at android.os.Looper.loop(Looper.java:135)
              at android.app.ActivityThread.main(ActivityThread.java:5221)
              at java.lang.reflect.Method.invoke(Native Method)
              at java.lang.reflect.Method.invoke(Method.java:372)
              at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:898)
              at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:693)
  </code></pre>
  
  <p>I don't Understand how i am getting a null object when i create the new Creator object to add to the ArrayList.</p>
  
  <p>Any pointers would be greatly appreciated.</p>