Populating List View of Objects dynamically in Android

Question

I've looked up a few tutorials online but decided the following was the best approach.

My Activity only consists of a text field (editText) and a list view (roomlv)

• CODE

The objects contained in the list are RoomCell objects

My Class has the following variables

public class RoomsActivity extends ActionBarActivity {

    ListView listview2;
    RoomCell[] roomcells = {rc1, rc2, rc3, rc4, rc5, rc6, rc7, rc8, rc9}; 
    //where rc1, rc2, ... are predefined objects
    RoomCell[] finalcells = roomcells;
    RoomListAdapter rla;

My onCreate method looks like this:

   @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_rooms);

        listview2 = (ListView) findViewById(R.id.roomlv);
        listview2.setClickable(true);
        listview2.setOnItemClickListener(onListClick2);

        EditText filterText = (EditText) findViewById(R.id.editText);
        filterText.addTextChangedListener(filterTextWatcher);

        rla = new RoomListAdapter(this, finalcells);
        listview2.setAdapter(rla);

    }

where my TextWatcher works like this:

private TextWatcher filterTextWatcher = new TextWatcher() {

    public void onTextChanged(CharSequence s, int start, int before,
                              int count) {
        if(s.length()==0){

            finalcells = roomcells;
            rla.notifyDataSetChanged();

        }else{

            finalcells = filterList(roomcells, s);
            rla.notifyDataSetChanged();

        }
    }
};

where the other 2 override methods are omitted for convenience here.

The filterList() method returns the filtered array (this, I believe is working fine but I will paste the code if asked for)

And finally the OnClick code is here:

private AdapterView.OnItemClickListener onListClick2 = new AdapterView.OnItemClickListener(){

    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {

        GlobVar.roomtitle = finalcells[position].name;
        GlobVar.roomsize = finalcells[position].size;

        Intent i = new Intent(RoomsActivity.this, TheRoomActivity.class);
        startActivity(i);
    }
};

where 2 global variables are assigned specific values to the clicked cells.

• PROBLEM

Editing the text field makes no difference whatsoever, and clicking on a cell crashes my program?

I've looked over my code countless times and cannot locate any mistakes.

Thanks for any help in advance.

Answer 1

You need to call:

rla = new RoomListAdapter(RoomsActivity.this, finalcells);
listview2.setAdapter(rla);

before calling:

rla.notifyDataSetChanged();

inside your onTextChanged method as it will have new filtered objects each time you type into your EditText