ListFragment and asynctask issues android

Question

I am trying to display a list fragment in the middle of my activity. The list fragment adapter is a custom adapter (extended from BaseAdapter) with the typical ViewHolder pattern. It is implemented correctly.

I have the adapter set up with greenrobot Eventbus to receive a new List object from an asynctask which does the query in the background (as not to slow down the UI Main Thread).

The problem is the list fragment doesn't have the results of the database query initially so it defaults to empty (and displays the textview in my xml for the main activity which has the id 'empty').

In the end, my adapter, and listviewfragment don't get instaniated at all because it defaults to empty.

Is there a better method to doing this? How can I get my listview fragment to wait for the data recieved from the asyncTask?

I am going to just do a fragment with a listview in it, instead of a listview fragment, and I'll see if that will help.

Answer 1

As I understood correctly, you did everything okay so far. What you have to do is to add an "update" method to your adapter, and call this whenever your asynctask finished it's job and got the results for you. This update method should look something like

public void updateAdapterData(List<String> newList) {
    mItems.clear(); // say mItems is the global list you have in the adpater
    mItems.addAll(newList);

    notifyDataSetChanged(); // This will cause the adpater to re-draw it's rows, so now data should be visible in your list
}

And in your fragment you do somehting like:

 adpater.updateAdapterData(newList);

Does this help?