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androidandroid-listviewandroid-cursoradapter

CursorAdapter implements Filterable


I have a custom CursorAdapter class that uses the alphabet indexer and I want to implement filterable, but I am having some problems getting it to function correctly.

    c = db.selectData();


    lv = (ListView) findViewById(android.R.id.list);
    searchTerm = (EditText) findViewById(R.id.inputSearch);

    lv.setFastScrollEnabled(true);

    adapter = new MyCursorAdapter(getApplicationContext(), R.layout.rowlayout, c, new String[]{"_id, name, company, job_title"},
            new int[]{R.id.company, R.id.job_title, R.id.name});

    adapter.setFilterQueryProvider(new FilterQueryProvider() {
        public Cursor runQuery(CharSequence constraint) {
            // Search for states whose names begin with the specified letters.
            Cursor cursor = db.searchAttendees(constraint.toString());
            return cursor;

        }
    });

    lv.setAdapter(adapter);

    getListView().setTextFilterEnabled(true);

    searchTerm.addTextChangedListener(new TextWatcher() {

        @Override
        public void onTextChanged(CharSequence s, int start, int before, int count) {
            System.out.println("Text ["+s+"]");
            adapter.getFilter().filter(s.toString());
        }

        @Override
        public void beforeTextChanged(CharSequence s, int start, int count,
                int after) {

        }

        @Override
        public void afterTextChanged(Editable s) {
        }
    });

  }

And this is the MyCustomAdapter class

        public class MyCursorAdapter extends CursorAdapter  implements SectionIndexer, Filterable
{

    AlphabetIndexer mAlphabetIndexer;

    public MyCursorAdapter(Context context, int simpleListItem1,
            Cursor cursor, String[] strings, int[] is)
    {
        super(context, cursor);
        mAlphabetIndexer = new AlphabetIndexer(cursor,
                cursor.getColumnIndex("name"),
                " ABCDEFGHIJKLMNOPQRTSUVWXYZ");
        mAlphabetIndexer.setCursor(cursor);//Sets a new cursor as the data set and resets the cache of indices.

    }

    /**
     * Performs a binary search or cache lookup to find the first row that matches a given section's starting letter.
     */
    @Override
    public int getPositionForSection(int sectionIndex)
    {
        return mAlphabetIndexer.getPositionForSection(sectionIndex);
    }

    /**
     * Returns the section index for a given position in the list by querying the item and comparing it with all items
     * in the section array.
     */
    @Override
    public int getSectionForPosition(int position)
    {
        return mAlphabetIndexer.getSectionForPosition(position);
    }

    /**
     * Returns the section array constructed from the alphabet provided in the constructor.
     */
    @Override
    public Object[] getSections()
    {
        return mAlphabetIndexer.getSections();
    }

    @Override
    public Cursor runQueryOnBackgroundThread(CharSequence constraint) {
        //What to do here?

    }

    /**
     * Bind an existing view to the data pointed to by cursor
     */
    @Override
    public void bindView(View view, Context context, Cursor cursor) {
        TextView name = (TextView)view.findViewById(R.id.name);
        name.setText(cursor.getString(
                cursor.getColumnIndex("name")));
        TextView company = (TextView)view.findViewById(R.id.company);
        company.setText(cursor.getString(
                cursor.getColumnIndex("company")));
        TextView jobTitle = (TextView)view.findViewById(R.id.job_title);
        jobTitle.setText(cursor.getString(
                cursor.getColumnIndex("job_title")));
    }

    /**
     * Makes a new view to hold the data pointed to by cursor.
     */
    @Override
    public View newView(Context context, Cursor cursor, ViewGroup parent) {
        LayoutInflater inflater = LayoutInflater.from(context);
        View newView = inflater.inflate(
                R.layout.attendee_item_row, parent, false);
        return newView;
    }

I know I need to use runQueryOnBackgroundThread but I don't know what I am meant to implement in this method. Could someone help me here? Or point me in the direction of some examples?

Thanks!


Solution

  • I know I need to use runQueryOnBackgroundThread but I don't know what I am meant to implement in this method.

    If you set a FilterQueryProvider on the CursorAdapter then you don't override that method(which by default calls the runQuery method of the FilterQueryProvider). When you want to filter the adapter simply call the getFilter().filter(constraint) method giving it the new constraint.