title: drag but empty clipdata
body: <p>I can't find where's the problem, that I think I put things into the item and clipdata right,
  however my onDrag always receive a null pointer exception and can't even get the number of item.</p>
  
  <p>this is my OnDragListener Class</p>
  
  <pre><code>    public class ScaleImageSize implements View.OnDragListener{
  
              @Override
              public boolean onDrag(View arg0, DragEvent arg1) {
                  // TODO Auto-generated method stub
                  final int action = arg1.getAction();                    
                  Integer tag  = (Integer) arg0.getTag();
                  Log.d("tag",Integer.toString(tag));
  
                  int count = arg1.getClipData().getItemCount();
                  Log.d("count",Integer.toString(count));
  
  
                  ClipData.Item item = arg1.getClipData().getItemAt(0);
                  String tagString = item.getText().toString();
                  int tagOfType = Integer.valueOf(tagString);
  
                  switch(action){
  
                  case DragEvent.ACTION_DRAG_STARTED:
  
                      return true;
                  case DragEvent.ACTION_DRAG_LOCATION:
                      augImg( tag, (int) arg1.getY());
  
                      augImg( tagOfType, (int)arg1.getY());
  
                      return true;
                  case DragEvent.ACTION_DROP:
  
                      return true;
                  }               
                  return false;
              }
  
          };
  </code></pre>
  
  <p>And this is my OnLonClickListener class which should call the function startdrag.</p>
  
  <pre><code>       OnLongClickListener StartScaleImageSize = new OnLongClickListener(){
  
          @Override
          public boolean onLongClick(View v) {
              // TODO Auto-generated method stub
              int i  =  (Integer) v.getTag();
              beingLongClick[i] = true;
  
              ClipData.Item item = new ClipData.Item((CharSequence)Integer.toString(i));
              String[] clipDescription = {ClipDescription.MIMETYPE_TEXT_PLAIN};
              ClipData dragData = new ClipData((CharSequence)Integer.toString(i), 
                      clipDescription,
                      item);
              dragData.addItem(item);
  
              DragShadowBuilder shadowBuilder = new View.DragShadowBuilder(v);
              v.startDrag(dragData, shadowBuilder, v, 0);
              return false;
          }
      };
  </code></pre>
  
  <p>and the <strong>error message</strong>:</p>
  
  <pre><code>06-24 21:47:21.205: E/AndroidRuntime(4123): FATAL EXCEPTION: main
  06-24 21:47:21.205: E/AndroidRuntime(4123): java.lang.NullPointerException
  06-24 21:47:21.205: E/AndroidRuntime(4123):     at traveler.com.TravelerpActivity$TypeMgr$ScaleImageSize.onDrag(TravelerpActivity.java:237)
  06-24 21:47:21.205: E/AndroidRuntime(4123):     at android.view.View.dispatchDragEvent(View.java:13619)
  06-24 21:47:21.205: E/AndroidRuntime(4123):     at android.view.ViewGroup.notifyChildOfDrag(ViewGroup.java:1287)
  06-24 21:47:21.205: E/AndroidRuntime(4123):     at android.view.ViewGroup.dispatchDragEvent(ViewGroup.java:1131)
  06-24 21:47:21.205: E/AndroidRuntime(4123):     at android.view.ViewGroup.notifyChildOfDrag(ViewGroup.java:1287)
  06-24 21:47:21.205: E/AndroidRuntime(4123):     at android.view.ViewGroup.dispatchDragEvent(ViewGroup.java:1131)
  06-24 21:47:21.205: E/AndroidRuntime(4123):     at android.view.ViewGroup.notifyChildOfDrag(ViewGroup.java:1287)
  06-24 21:47:21.205: E/AndroidRuntime(4123):     at android.view.ViewGroup.dispatchDragEvent(ViewGroup.java:1131)
  06-24 21:47:21.205: E/AndroidRuntime(4123):     at android.view.ViewGroup.notifyChildOfDrag(ViewGroup.java:1287)
  06-24 21:47:21.205: E/AndroidRuntime(4123):     at android.view.ViewGroup.dispatchDragEvent(ViewGroup.java:1131)
  06-24 21:47:21.205: E/AndroidRuntime(4123):     at android.view.ViewRootImpl.handleDragEvent(ViewRootImpl.java:3471)
  06-24 21:47:21.205: E/AndroidRuntime(4123):     at android.view.ViewRootImpl.handleMessage(ViewRootImpl.java:2620)
  06-24 21:47:21.205: E/AndroidRuntime(4123):     at android.os.Handler.dispatchMessage(Handler.java:99)
  06-24 21:47:21.205: E/AndroidRuntime(4123):     at android.os.Looper.loop(Looper.java:137)
  06-24 21:47:21.205: E/AndroidRuntime(4123):     at android.app.ActivityThread.main(ActivityThread.java:4441)
  06-24 21:47:21.205: E/AndroidRuntime(4123):     at java.lang.reflect.Method.invokeNative(Native Method)
  06-24 21:47:21.205: E/AndroidRuntime(4123):     at java.lang.reflect.Method.invoke(Method.java:511)
  06-24 21:47:21.205: E/AndroidRuntime(4123):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
  06-24 21:47:21.205: E/AndroidRuntime(4123):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
  06-24 21:47:21.205: E/AndroidRuntime(4123):     at dalvik.system.NativeStart.main(Native Method)
  </code></pre>
  
  <p>pls, any advice would be great thks!</p>