MergeAdapter - can't retrieve section position

Question

I am looking to integrate MergeAdapter into my project and I am having an issue trying to retrieve which section the user has clicked. I want to set it up so when user clicks any item in any section, the section number is returned so I know which section the user is in. The app I am working on requires this.

Code below sets up 3 sections with some data in each section.

public class SectionTesting extends Activity
{

    ListView listView;
    private MergeAdapter mergeAdapter = null;

    private static final String[] items =
    { "One", "Two", "Three" };

    Context context;

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.mergelayout);

        context = this;

        listView = (ListView) findViewById(R.id.mergeListView);

        mergeAdapter = new MergeAdapter();

        ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
                android.R.layout.simple_list_item_1, new ArrayList<String>(
                        Arrays.asList(items)));

        TextView sectionHeader = new TextView(this);
        sectionHeader.setText("Section One");

        mergeAdapter.addView(sectionHeader);
        mergeAdapter.addAdapter(adapter);

        TextView sectionHeaderTwo = new TextView(this);
        sectionHeaderTwo.setText("Section Two");

        mergeAdapter.addView(sectionHeaderTwo);
        mergeAdapter.addAdapter(adapter);

        TextView sectionHeaderThree = new TextView(this);
        sectionHeaderThree.setText("Section Three");

        mergeAdapter.addView(sectionHeaderThree);
        mergeAdapter.addAdapter(adapter);

        listView.setAdapter(mergeAdapter);

        listView.setOnItemClickListener(new OnItemClickListener()
        {
            @Override
            public void onItemClick(AdapterView<?> arg0, View v, int position,
                    long arg3)
            {
                Toast.makeText(
                        context,
                        "You clicked Section "
                                + mergeAdapter.getSectionForPosition(position),
                        Toast.LENGTH_SHORT).show();

            }

        });
    }

}

I was hoping getSectionForPosition method would return the value I require, but it just returns 0 everytime. I tried calling the method getSections().length as well to check it was returning the correct number of sections, but again it comes back as 0 everytime.

Any help would be much appreciated!!

Edit

I managed to come up with this messy solution. In the MergeAdapter class, under the addView method, I added this line of code

view.setId(1000);

Then I added this method here

public int getSectionNumber(int position)
    {
        int section = 0;

        for (ListAdapter piece : getPieces())
        {
            int size = piece.getCount();

            if (position < size)
            {
                return section-=1;
            }

            position -= size;

            if(size == 1)
            {
                if(piece.getItem(0) instanceof TextView)
                {
                    TextView tv = (TextView) piece.getItem(0);
                    if(tv.getId() == 1000)
                    {
                        section++;  
                    }
                }       
            }
        }

        return (-1);
    }

The code seems to work fine, its just a bit sloppy I think. If anyone can come up with a cleaner solution that would be much appreciated, if not, then I will just add this as the answer when I can and accept it

Answer 1

You have at least two problems:

1. In order to use getSectionForPosition(), your Adapter has to implement the SectionIndexer interface. ArrayAdapter<> does not. All MergeAdapter does is try to use any SectionIndexer implementations passed to it, and you have passed zero such implementations.

2. You are trying to reuse the same Adapter instance several times inside of the MergeAdapter, and I have no idea if that will work and certainly do not recommend it.

To address these, create individual adapters per section, and have those adapters implement SectionIndexer.