Reputation: 2480

ListView doesn't update itself

I have a display of some data on one fragment, and each time I click on a button it should add to the listView in the second fragment. For some reason when I click the button I the listView doesn't change.

fragment1 :

nextButton.setOnClickListener(new View.OnClickListener() {
                public void onClick(View v) 
                {            
                    HistoryFragment.addToHistory( myObject );
                }});

HistoryFragment (listView) :

public class HistoryFragment extends ListFragment
{ 
    private static List<Password> historyList = new ArrayList<MyObject>();

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        historyList = myManager.getMyObjects ();
    }

    public static void addToHistory( MyObject myObject )
    {
        historyList.add( myObject );
    }

  @Override
  public View onCreateView(LayoutInflater inflater, ViewGroup         container, Bundle savedInstanceState) { 
    View view = inflater.inflate(R.layout.fragment_history, container, false);
    MyObjectAdapter adapter = new MyObjectAdapter( historyList );
    setListAdapter(adapter);
    return view;
}
    ....
    ....
    ....
private class MyObjectAdapter extends BaseAdapter
    {
        private final ArrayList<MyObject> data; 

        public MyObjectAdapter( List<MyObject> historyList ) 
        {
            data = new ArrayList<MyObject>();
            data.addAll( historyList );
        }

        @Override
        public int getCount() 
        {
            return data.size();
        }

        @Override
        public MyObject getItem( int position ) 
        {            
            return data.get( position );
        }

        @Override
        public long getItemId(int position) {
            // TODO implement you own logic with ID
            return 0;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            final View result;

            notifyDataSetChanged();

            if (convertView == null) 
            {
                result = LayoutInflater.from(parent.getContext()).inflate(R.layout.history_list_item, parent, false);
            } 
            else 
            {
                result = convertView;
            }

            MyObject item = getItem( position );

            ( (TextView) result.findViewById(R.id.historyObjectTextView) ).setText(item.toString());

            return result;
       }
    }

fragment main(1) :

  public class MainFragment extends Fragment 
 {
 Map<String,MyObject> objects  = new HashMap<String,MyObject>();
 List< MyObject > objectsList = new ArrayList< MyObject >();
 TextView nextDisplay;

@Override
 public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
objects = myManager.getInstance().getObjects();
objectsList = MyObject.getObjectsList();
}

@Override
 public View onCreateView( LayoutInflater inflater, ViewGroup                     container, Bundle savedInstanceState ) 
 {
    View view = inflater.inflate(R.layout.fragment_main, container,   false);

nextDisplay = ( TextView ) view.findViewById( R.id.displayTextView );
nextDisplay.setText( objectsList.get( 0 ).getObjectString() );

Button nextButton = ( Button ) view.findViewById( R.id.nextObjectButton );
nextButton.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) 
        {            
            if( objectsList.size() > 0 )
            {
                objects.get(objectsList.get( 0 ).getObjectString()).setTried( true );
                long currentTime = System.currentTimeMillis();
                objects.get(objectsList.get( 0 ).getObjectString()).setTime( currentTime );


                HistoryFragment.addToHistory( objectsList.get( 0 ) );
                objectsList.remove( 0 );

                if( objectsList.size() > 0  && !objectsList.get( 0 ).getTried() )
                {
                    nextCodeDisplay.setText( objectsList.get( 0 ).getObjectString() );
                }
            }           
        }});
return view;

}

Upvotes: 1

Answers (3)

doubleA

Reputation: 2456

Like This.

private List<Password> historyList = new ArrayList<MyObject>();
private MyObjectAdapter adapter
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { 
    View view = inflater.inflate(R.layout.fragment_history, container, false);
    adapter = new MyObjectAdapter( historyList );
    setListAdapter(adapter);
    return view;
}

private static List<Password> historyList = new ArrayList<MyObject>();

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    historyList = myManager.getMyObjects ();
}

public void addToHistory( MyObject myObject )
{
    historyList.add( myObject );
    adapter.notifyDataSetChanged();
}

Upvotes: 1

Gabriele Mariotti

Reputation: 363975

To populate or update the ListView you have to update the list used by the adapter. In your code you are updating the list inside the Fragment, not the data used by the adapter.

In your code you should do something like this:

adapter.add(MyObject myObject);

in your adapter:

private class MyObjectAdapter extends BaseAdapter{

    public  void add( List<MyObject> historyList ) 
        {
            if (data == null)
               data = new ArrayList<MyObject>();
            data.addAll( historyList );
            notifyDataSetChanged();
        }


}

Upvotes: 1

Teo Inke

Reputation: 5986

Try calling notifyDataSetChanged() on the OnClickListener:

nextButton.setOnClickListener(new View.OnClickListener() {
                public void onClick(View v) 
                {            
                    HistoryFragment.addToHistory( myObject );
                    notifyDataSetChanged();
                }});

Upvotes: 0

ListView doesn&#39;t update itself

Answers (3)

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ListView doesn't update itself