title: getPosition(item) from ArrayAdapter<String> gives NullPointerException
body: <p>I tried to search for my problem, but without success.
  I am filling <code>ArrayAdapter&lt;String&gt; parkingLotAdapter</code> from database(Parse.com). I assign this adapter to spinner. Spinner works fine, show list of items. But when I try to get position one of the item in the Adapter via <code>getPosition(item)</code> I get NullPointerException.</p>
  
  <pre><code>List&lt;String&gt; list = new ArrayList&lt;String&gt;();
  
  for (ParseObject temp : parkingList) {
       list.add(temp.getString("parking_lot"));
       }
  parkingLotAdapter = new ArrayAdapter&lt;String&gt;(getActivity(),
  android.R.layout.simple_spinner_item, list);
  parkingLotAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
  parkinglotSpinner.setAdapter(parkingLotAdapter);
  
  int pos4 = parkingLotAdapter.getPosition("A123");
  parkinglotSpinner.setSelection(pos4);
  </code></pre>
  
  <p>When I use <code>getPosition(item)</code> with other spinners which I populate from Resources and use <code>ArrayAdapter&lt;CharSequence&gt;</code>, everything works good. Can you help me with this issue.</p>
  
  <p>My Logcat:</p>
  
  <pre><code>06-17 09:40:13.927: W/dalvikvm(26031): threadid=1: thread exiting with uncaught exception (group=0x41307300)
  06-17 09:40:13.927: E/AndroidRuntime(26031): FATAL EXCEPTION: main
  06-17 09:40:13.927: E/AndroidRuntime(26031): java.lang.NullPointerException
  06-17 09:40:13.927: E/AndroidRuntime(26031):    at me.aizon.app.fragments.RegisterFragment$LoadParkingSpinnerASYNC.onPostExecute(RegisterFragment.java:396)
  06-17 09:40:13.927: E/AndroidRuntime(26031):    at me.aizon.app.fragments.RegisterFragment$LoadParkingSpinnerASYNC.onPostExecute(RegisterFragment.java:1)
  06-17 09:40:13.927: E/AndroidRuntime(26031):    at android.os.AsyncTask.finish(AsyncTask.java:631)
  06-17 09:40:13.927: E/AndroidRuntime(26031):    at android.os.AsyncTask.access$600(AsyncTask.java:177)
  06-17 09:40:13.927: E/AndroidRuntime(26031):    at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:644)
  06-17 09:40:13.927: E/AndroidRuntime(26031):    at android.os.Handler.dispatchMessage(Handler.java:99)
  06-17 09:40:13.927: E/AndroidRuntime(26031):    at android.os.Looper.loop(Looper.java:137)
  06-17 09:40:13.927: E/AndroidRuntime(26031):    at android.app.ActivityThread.main(ActivityThread.java:4746)
  06-17 09:40:13.927: E/AndroidRuntime(26031):    at java.lang.reflect.Method.invokeNative(Native Method)
  06-17 09:40:13.927: E/AndroidRuntime(26031):    at java.lang.reflect.Method.invoke(Method.java:511)
  06-17 09:40:13.927: E/AndroidRuntime(26031):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:917)
  06-17 09:40:13.927: E/AndroidRuntime(26031):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:684)
  06-17 09:40:13.927: E/AndroidRuntime(26031):    at dalvik.system.NativeStart.main(Native Method)
  </code></pre>