ListView不会使用notifyDataSetChanged刷新

Question

I'm trying to refresh the listview from the adapter class ( non activity class) I tried notifyDataSetChanged() but it wont work , I also tried to call the displayListView() in the adapter class but it crashes as well

this is my displayListView() Method in The ActivityClass

            Cursor cursor = dbHelper.fetchAllCountries();

            // The desired columns to be bound
            String[] columns = new String[]{
                   DBAdapter.qty,
                   DBAdapter.price,
                   DBAdapter.PRODUCT_NAME
            };

            // the XML defined views which the data will be bound to
            int[] to = new int[]{
                    R.id.qtyL,
                    R.id.priceL,
                    R.id.PRODUCT_NAMEL
            };

            // create the adapter using the cursor pointing to the desired data
            //as well as the layout information
            dataAdapter = new SimpleCursorAdapter(
                    this, R.layout.country_inf,
                    cursor,
                    columns,
                    to,
                    0);

            HorizontalListView listView = (HorizontalListView) findViewById(R.id.cartCeckOutList);
            // Assign adapter to ListView
                    listView.setAdapter(dataAdapter);
                    dataAdapter.notifyDataSetChanged();

And this is the Adapter Class I use

        package com.abdullahadhaim.finegrillresturant.adater;



public class CustomListAdapter extends BaseAdapter {
Context c;
// DBHelper myDataBaseHelper ;
private Activity activity;
private LayoutInflater inflater;
private List<Movie> movieItems;
ImageLoader imageLoader = AppController.getInstance().getImageLoader();

DBAdapter myADapterDB;

WaiterActivity waiterAct;

public CustomListAdapter(Activity activity, List<Movie> movieItems) {
    this.activity = activity;
    this.movieItems = movieItems;
}

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

@Override
public Object getItem(int location) {
    return movieItems.get(location);
}

@Override
public long getItemId(int position) {
    return position;
}

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

    if (inflater == null)
        inflater = (LayoutInflater) activity
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    if (convertView == null)
        convertView = inflater.inflate(R.layout.list_row, null);

    if (imageLoader == null)
        imageLoader = AppController.getInstance().getImageLoader();
    NetworkImageView thumbNail = (NetworkImageView) convertView
            .findViewById(R.id.thumbnail);

    final TextView title = (TextView) convertView.findViewById(R.id.title);
    TextView price = (TextView) convertView.findViewById(R.id.rating);
    // myDataBaseHelper=new DBHelper(activity, "CDB", null, 1);
    myADapterDB = new DBAdapter(activity);
    myADapterDB.open();
    waiterAct = new WaiterActivity();

    // getting movie data for the row
    final Movie m = movieItems.get(position);

    // thumbnail image
    thumbNail.setImageUrl(m.getThumbnailUrl(), imageLoader);

    // title
    title.setText(m.getTitle());

    // price
    price.setText("Price: " + "SR " + String.valueOf(m.getPrice()));

    Button add = (Button) convertView.findViewById(R.id.button1);
    Button plus = (Button) convertView.findViewById(R.id.plus_butt);
    Button minus = (Button) convertView.findViewById(R.id.minus_butt);
    final EditText qty = (EditText) convertView
            .findViewById(R.id.editText1);

    plus.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            String the_qty = qty.getText().toString();
            int my_qty = Integer.parseInt(the_qty) + 1;
            qty.setText(my_qty + "");

        }
    });

    minus.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            String the_qty = qty.getText().toString();
            int my_qty = Integer.parseInt(the_qty) - 1;
            qty.setText(my_qty + "");

        }
    });

    add.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
            int myQTY = Integer.parseInt(qty.getText().toString());
            String myTitle = m.getTitle().toString();
            String myCategory = m.getCategory().toString();
            int myCategoryN = m.getOrderNum();
            double myPrice = m.getPrice() * myQTY;

            if (myQTY == 0)
                Toast.makeText(activity, "Orders Must be 1 Atleast",
                        Toast.LENGTH_SHORT).show();

            else {

                myADapterDB.checkIfExcist(activity, "productName", myTitle,
                        myQTY, myPrice, m.getPrice(), myTitle, myCategory,
                        myCategoryN + "", myQTY);
                myADapterDB.deleteZeroOrLessValues();


            }

        }
    });

    return convertView;
}

public void notifyDataSetChanged() {
    // TODO Auto-generated method stub
    super.notifyDataSetChanged();
}


}

Answer 1

take a look at Loaders. I think this is the prefered way to load data from datebase into views. With Loaders you get callbacks if the data has changed and the view is updated for you.

http://developer.android.com/guide/components/loaders.html

Here is a good tutorial I think: http://code.tutsplus.com/tutorials/android-fundamentals-properly-loading-data--mobile-5673