2

My Custom Adapter that extends SimpleCursorAdapter for my ListFragment does not display the items in my database correctly. it does not display the text in the TextView, what else do I have to do to the cursor for it to show the correct text?

I thought I had to override the bindView but that had no effect

Setting the adapter:

public void populateList(){

        String[] fields = new String[] {BowlersDB.NAME};
        Cursor c = getActivity().getContentResolver().query(BowlersDB.CONTENT_URI,
                new String[] {BowlersDB.ID,BowlersDB.NAME},null,null,BowlersDB.NAME + " COLLATE LOCALIZED ASC");

mAdapter = new CheckAdapter(getActivity(),R.layout.check_listview,c,fields,new int[] {R.id.nameCheckTV});


        setListAdapter(mAdapter);   

        getLoaderManager().initLoader(0,null,this);
    }

Adapter:

public class CheckAdapter extends SimpleCursorAdapter{

    Context context;
    Cursor c;

    public CheckAdapter(Context context, int layout, Cursor c,String[] from, int[] to) {
        super(context, layout, c, from, to);
        this.context = context;
        this.c = c;
        // TODO Auto-generated constructor stub
    }

    @Override
    public void bindView(View view,Context context,Cursor cursor){
        String st = cursor.getString(cursor.getColumnIndex(BowlersDB.NAME));

        TextView tv = (TextView)view.findViewById(R.id.nameCheckTV);
        tv.setText(st);
    }

    @Override
    public View getView(final int position,View convertView,ViewGroup parent){
        if(convertView == null){
            LayoutInflater inflator = getLayoutInflater();
            convertView = inflator.inflate(R.layout.check_listview,null);
        }

        CheckBox cb = (CheckBox)convertView.findViewById(R.id.checkBox1);   
            cb.setOnClickListener(new OnClickListener(){

                @Override
                public void onClick(View v) {
                    CheckBox check = (CheckBox)v.findViewById(R.id.checkBox1);
                    int pos = position;
                    if(check.isChecked()){
                        mCheckedItems.add(position);
                    }else if(!check.isChecked()){
                        for(int i=0;i< mCheckedItems.size();i++){
                            if(mCheckedItems.get(i) == position){
                                mCheckedItems.remove(i);
                            }
                        }
                    }
                }

            });
        return convertView;
    }

}
Alex Lockwood
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tyczj
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  • the constructor you are currently using is deprecated and may result in poor responsiveness. use the second one described here: http://developer.android.com/reference/android/widget/SimpleCursorAdapter.html – Alex Lockwood Jan 17 '12 at 22:01
  • i'm also unsure why you are directly querying for a `Cursor` in your `onCreate()` method. if you are implementing the `LoaderManager.LoaderCallbacks` then this should be done for you by the system (assuming you have implemented your `onCreateLoader()` method correctly). – Alex Lockwood Jan 17 '12 at 22:07
  • In your bindView method, try logging the st String. – Krylez Jan 17 '12 at 22:20
  • it seems bindView is never getting called – tyczj Jan 17 '12 at 22:36

1 Answers1

6

I think I got it. Check out the implementation for CursorAdapter.getView(). Notice how bindView() and newView() are called within getView(). It looks like by overriding getView() you are ensuring that your CursorAdapter never calls bindView(). Either put everything ONLY in getView() or ONLY in newView() and bindView(), but not both.


EDIT I:

Four things:

  1. I've read up on CursorAdapters and it looks like you want to override bindView() instead of getView(). It looks like getView() is called twice for each row that's to be displayed and this is somehow preventing the cursor from being updated and thus always points to the first row. I think this is why your ListView only displays the first row. Further, the default CursorAdapter implementation for a ListView will recycle views for you, so overriding getView() really isn't necessary (check out this answer for more info).

  2. When creating your mAdapter, you should pass a null Cursor into the constructor. The Cursor will be delivered in onLoadFinished (when the Loader has finished the query) and will be bound to the adapter with swapCursor(cursor).

  3. Your onCreateLoader() method will create (or start) the Loader that will perform the initial query. Make sure it looks something like this,

    @Override
    public Loader<Cursor> onCreateLoader(int id, Bundle args) {
        String[] projection = { BowlersDB.ID, BowlersDB.NAME };
    
        CursorLoader cursorLoader = new CursorLoader(getActivity(),
                BowlersDB.CONTENT_URI, projection, null, null, null);
        return cursorLoader;
    }
    
  4. Make sure you make use of the correct SimpleCursorAdapter constructor... the one you are currently using is deprecated! (pass 0as a flag... the CursorLoader will register a content observer for you so you don't need to pass in anything special).


EDIT II:

To clarify, the bindView() method is where you populate your row's widgets with the data from the Cursor's current position. You are handed the Cursor pre-positioned at the proper row. You need to pull data out of the Cursor and pour it into your desired widgets. In other words, you'll need to query for the row's id (instead of using the "position" argument in getView()). Try setting the onClickListener in bindView() with something like:

final int rowId = cursor.getInt(cursor.getColumnIndex("_id"));

CheckBox cb = (CheckBox)convertView.findViewById(R.id.checkBox1);   
cb.setOnClickListener(new OnClickListener() {
    @Override
    public void onClick(View v) {
        int position = rowId;
        /* you now know this row's position. do what you need to do. */
    }
});
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Alex Lockwood
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  • I originally did that but when trying to use the cursor I would get NullPointerException because there was no cursor fed in which is why I had that query in the create method. when doing that the listview would only display the first row in the cursor so it seems I would then have to iterate through the cursor but how i guess is the question. if it was an array I would just use the position variable but I cant use that with a cursor – tyczj Jan 17 '12 at 23:04
  • the reason I was using `getView()` is because when the checkbox is clicked the `onclicklistener` in the `getView` knows the position checked so using the `bindView` would then again bring me back to the problem of getting the id of the list item checked. I was going off of this example hor help http://www.vogella.de/articles/AndroidListView/article.html#listadvanced_interactive – tyczj Jan 18 '12 at 03:15