Trigger a method creates ListView in fragment from inner class, but content of ListView is disappeared sometimes

Question

I have a bug in my code, but I couldn't figure out WHY because sometimes it works sometime it doesn't. Hope you can help me point out the problem. Here is issue:

In a fragment, I setup a Gridview + ListView. When user click on a gridcell (the cell highlighted) then I display info of that cell is on the ListView (This work just fine if user perform physical click action). I also have buttons to regenerate data of for the GridView and will perform a click AUTOMATICALLY. The data of GridView generated correctly and a cell is highlighted as expected (This is performed in the inner class), but the ListView is not rendered(This is performed in fragment). I did debug and lines are executed as expected but nothing happened. However sometime, I click on same button with different input data and it works.

Below are sample flow of my class when a tool bar button clicked:

1. toolbarButtonsAction (method 1)

2. The inner class

   • Generate Data
   • Perform Click automatically :Trigger method 2 in the fragment to refresh the ListView

3. The refreshListView method is called and every single line of code is executed as expected.

   public class GridListViewFragment extends Fragment { @Override public void onActivityCreated(Bundle savedInstanceState) { //General Lifecycle setup. //Too much to list here.....

   m_listView = (ListView)getView().findViewById(R.id.eventsList);
   
   }
   
   //Method 1
   View.OnClickListener toolbarButtonsAction = new View.OnClickListener() 
   {
       // Each view will return different input data each time clicked
       // This will call the inner class GridCellAdapter
       // The inner class will generate data to display on grid cell
       // If necessary, performClick() automatically 
   
   }
   
   //Method 2
   public void refreshListView()
   {
       //This method will be triggered from ome method in the inner class
   
       // I'm sure the Arraylist is valid
       if (anArrayList.size() == 0)
   {
       String[] notAvail = new String[]{"NotAvail String."};
       ArrayAdapter<String> nullAdapter = new ArrayAdapter<String>
       (getActivity(),android.R.layout.simple_list_item_2, android.R.id.text2, notAvail);          
       m_listView.setClickable(false);
       m_listView.setEnabled(false);
       m_listView.setAdapter(nullAdapter);
   
   }else{
   
   
       ListViewAdapter lviewAdapter = new ListViewAdapter(getActivity(),anArrayList);
       lviewAdapter.notifyDataSetChanged();
       // Set adapter for ListView
       m_listView.setClickable(true);
       m_listView.setEnabled(true);
       m_listView.setAdapter(lviewAdapter);
   
   }
   
   
   }
   
   
   //This is inner class
   
   public class GridCellAdapter extends BaseAdapter implements OnClickListener
   {
   
   //Other methods....
   
    @Override
    public void onClick(View view)
     {
         //Generate data for the anArrayList
         //Call the refreshListView in the fragment.
         refreshListView();
     }
   } 
   

Update: It looked like the content of the ListView is disappeared, but the ListView is still showing. I checked by set color to background of the ListView.

Update2: getView() in ListViewAdapter in some case is not get called. This is issue

Answer 1

After having a chat discussion we came to a resolution. Let me qoute:

The issue is the getView() in listViewAdapter is not getting called sometime due to listView and its activity TabHost layout. Now I change android:layout_height="fill_parent" in main_activity and list view layout to android:layout_height="wrap_content"

So all along there was a layout error which indeed are hard to find sometimes and can be very mean.