使用唯一标题在购物车中添加多个项目

Question

我正在编写购物车应用程序，其中我需要允许用户在购物车中添加多个商品，就像我们在其他购物车应用中看到的一样。

在这里，我编写了一个代码，用于在购物车中添加商品，但不允许用户在购物车中添加多个商品。

而且我也不想在列表中显示重复的项目

Constants.java： -

public class Constants {
    public static ArrayList<HashMap<String, String>> sItem_Detail = new ArrayList<HashMap<String, String>>();
}

LazyAdapter.java： -

public class LazyAdapter extends BaseAdapter {

    private Activity activity;
    private ArrayList<HashMap<String, String>> data;
    private static LayoutInflater inflater=null;
    public ImageLoader imageLoader; 
    String itemTitle, itemCost;
    TextView title, cost;

    public LazyAdapter(Activity a, ArrayList<HashMap<String, String>> d) {
        activity = a;
        data=d;
        inflater = (LayoutInflater)activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        imageLoader=new ImageLoader(activity.getApplicationContext());
    }

    public int getCount() {
        return data.size();
    }

    public Object getItem(int position) {
        return position;
    }

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

    public View getView(int position, View convertView, ViewGroup parent) {
        View vi=convertView;
        if(convertView==null)
            vi = inflater.inflate(R.layout.listrow_items, null);

        title = (TextView)vi.findViewById(R.id.title); 
        cost = (TextView)vi.findViewById(R.id.cost); 
        ImageView thumb_image = (ImageView) vi.findViewById(R.id.list_image);


        HashMap<String, String> item = new HashMap<String, String>();
        item = data.get(position);

        // Setting all values in listview
        title.setText(item.get(ItemsActivity.KEY_TITLE));
        cost.setText(item.get(ItemsActivity.KEY_COST));
        imageLoader.DisplayImage(item.get(com.example.sample.ItemsActivity.KEY_THUMB_URL), thumb_image);

        //Button mImgAddCart
        Button mImgAddCart = (Button) vi.findViewById(R.id.btn_add_to_order);
        mImgAddCart.setOnClickListener(new OnClickListener() {

                public void onClick(View v) {
                    // TODO Auto-generated method stub
                    itemTitle = title.getText().toString();
                    itemCost = cost.getText().toString();   

                    if (Constants.sItem_Detail.size() <= 0) {
                        HashMap<String, String> sTempObj = new HashMap<String, String>();
                        sTempObj.put(ItemsActivity.KEY_TITLE, itemTitle);
                        sTempObj.put(ItemsActivity.KEY_COST, itemCost);
                        Constants.sItem_Detail.add(sTempObj);
                    }

                    AlertDialog.Builder alertdialog = new AlertDialog.Builder(
                            activity);
                    alertdialog.setTitle(activity.getResources()
                            .getString(R.string.app_name));
                    alertdialog.setMessage("Item Added to Cart");

                    alertdialog.setPositiveButton("OK",
                            new DialogInterface.OnClickListener() {
                                public void onClick(DialogInterface dialog,
                                        int which) 
                                {
                                    activity.finish();
                                }
                            });     
                    alertdialog.show();         
                }
            });

        return vi;
    }
}

请告诉我代码，我需要编写以实现此目的......

注意： 我仍然只获得列表中的单个项目