Android如何刷新或重新加载列表视图数据和最终总计数据

Question

Android如何刷新或重新加载listview数据和最终总计数据，这些数据是购物车总价的总和

check image i want the blue circle price add and show on the red circle and but if i delete or change quantity of product then also update the price in red circle

这是我的代码

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

   final ViewHolderItem viewHolder;
    if(convertView==null){
        inflater = ((Activity) context).getLayoutInflater();
        convertView = inflater.inflate(R.layout.cart_item, parent, false);
        viewHolder = new ViewHolderItem();
        viewHolder.toptext = (TextView) convertView.findViewById(R.id.cartname);
        viewHolder.prc = (TextView) convertView.findViewById(R.id.textView76);
        viewHolder.shp = (TextView) convertView.findViewById(R.id.textView77);
        viewHolder.subtotal = (TextView) convertView.findViewById(R.id.textView79);
        //viewHolder.textView80 = (TextView) convertView.findViewById(R.id.textView80);
        viewHolder.img = (ImageView) convertView.findViewById(R.id.imageView7);
        viewHolder.imageView2 = (ImageView) convertView.findViewById(R.id.imageView2);
        viewHolder.spinner = (Spinner)convertView.findViewById(R.id.spinner);
        convertView.setTag(viewHolder);

    }else{
        viewHolder = (ViewHolderItem) convertView.getTag();
    }

    final CartResponse response = getItem(position);
    int subtotal1=0;
    mydb = new DBHelper(getContext());

    if(response != null) {
       /* ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(getContext(),
                R.array.qty, android.R.layout.simple_spinner_item);
        adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        viewHolder.spinner.setAdapter(adapter);*/
        viewHolder.spinner.setSelection(Integer.parseInt(response.getQty())-1);

        viewHolder.spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {

            @Override
            public void onItemSelected(AdapterView<?> parent, View view,
                                       int pos, long id) {
                response.setQty(viewHolder.spinner.getSelectedItem()+"");
                if(mydb.updateContact(Integer.parseInt(response.getid()),response.getPname(),Integer.parseInt(response.getPrice()),Integer.parseInt(response.getCutPrice()),++pos,Integer.parseInt(response.getShipping()),response.getPhoto())){
                    Log.d("key",""+response.getQty());
                    updateResults();
                    //Toast.makeText(getContext(),"updated", Toast.LENGTH_SHORT).show();
                }

            }

            @Override
            public void onNothingSelected(AdapterView<?> parent) {
                // TODO Auto-generated method stub

            }
        });

        viewHolder.imageView2.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                mydb.deleteContact(Integer.parseInt(response.getid()));
                //int index =callback.indexOf(response.getid());
                callback.remove(response);
                updateResults();
                Toast.makeText(getContext(),"Remove", Toast.LENGTH_SHORT).show();
            }
        });
int tamount=0,tship=0,gt=0;
        tamount=tamount+(Integer.parseInt(response.getPrice())* Integer.parseInt(response.getQty()));

        tship=tship+(Integer.parseInt(response.getShipping())* Integer.parseInt(response.getQty()));

        gt=tamount+tship;

        subtotal1=Integer.parseInt(response.getPrice()) + Integer.parseInt(response.getShipping());
        viewHolder.toptext.setText(response.getPname());
        viewHolder.prc.setText("Rs."+tamount);
        //Log.d("key",""+response.getPrice());
        viewHolder.shp.setText("Rs."+tship);
        viewHolder.subtotal.setText("Sub total Rs."+gt);
        Picasso.get().load("https://www.exmple.com/photos/"+response.getPhoto()+".png").placeholder(R.drawable.placeholder).memoryPolicy(MemoryPolicy.NO_CACHE).networkPolicy(NetworkPolicy.NO_CACHE).into(viewHolder.img);
    }

购物车课程

public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    view=inflater.inflate(R.layout.fragment_cart, container, false);
    mydb = new DBHelper(getContext());

    cart_list = mydb.getAllCotacts();
    cartitems=cart_list.size();
    int amount=0,shping=0;
    for(int i=0;i<cartitems;i++){
        int price = (Integer.parseInt(cart_list.get(i).getPrice())*Integer.parseInt(cart_list.get(i).getQty()));
        int shp=(Integer.parseInt(cart_list.get(i).getShipping())*Integer.parseInt(cart_list.get(i).getQty()));
        amount=amount+price;
        shping=shping+shp;
    }
    TextView cout=(TextView)view.findViewById(R.id.textView75);
    TextView gprice=(TextView)view.findViewById(R.id.textView87);
    TextView gship=(TextView)view.findViewById(R.id.textView88);
    gprice.setText("Rs."+amount);
    gship.setText("Rs."+shping);
    if(cartitems>0){
        cout.setText("Your Cart Item");
    }else{
        cout.setText("Shopping Cart is Empty");
    }

    final CartAdapter adapter = new CartAdapter(getContext(), R.layout.cart_item, cart_list);
    final ListView order_list = (ListView)view.findViewById(R.id.cartlist);
    order_list.setAdapter(adapter);
    adapter.notifyDataSetChanged();
    order_list.setOnItemClickListener(new AdapterView.OnItemClickListener() {

        public void onItemClick(AdapterView<?> parent, View view,
                                int position, long id) {
            adapter.notifyDataSetChanged();
            //mydb.deleteContact(cart_list.get(position).getid());
            //Log.d("key",""+cart_list.get(position).getQty());
            //cart_list.get(position).getid();
        }});
    return view;
}