android - 在 Android 中，如何在不获取之前的订单商品的情况下将已订购商品入围？

Question

在我的应用程序中，当我选择要订购的商品时，所选商品会在已订购页面中入围。当我单击“订购”按钮时，选定的项目将存储在数据库中。这里的问题是当我选择一个项目并再次订购时，如果我选择要订购的项目，以前订购的项目也会在“已订购”页面中列入候选名单。请帮我解决这个问题。

public class SelectedItem extends Activity {
    private ListView lv;
    private CustomAdapter adapter;
    int tableid;
    String id;
    ArrayList<String> arr = new ArrayList<String>();
    ArrayList<String> price = new ArrayList<String>();
    ArrayList<Bitmap> image = new ArrayList<Bitmap>();
    Double amountvalue;
    TextView totalamount;
    Button order;
    String dtotalamount;

    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        arr = getIntent().getStringArrayListExtra("itemname");
        price = getIntent().getStringArrayListExtra("itemprice");

        image = getIntent().getExtras().getParcelableArrayList("itemimage");

        setContentView(R.layout.selecteditem);
        lv = (ListView) findViewById(R.id.selecteditemlist);
        adapter = new CustomAdapter(this, arr, price, image);
        lv.setAdapter(adapter);
        amountvalue = CustomAdapter.x;

        System.out.println(amountvalue);
        totalamount = (TextView) findViewById(R.id.amount);
        totalamount.setText(String.valueOf(amountvalue));
        order = (Button) findViewById(R.id.order);
        order.setOnClickListener(new OnClickListener() {

            public void onClick(View v) {
                try {
                    tableid = Login.tableid;
                    id = Integer.toString(tableid);
                    System.out.println(id);
                    String x = amountvalue.toString();
                    System.out.println(x);
                    ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
                    nameValuePairs
                            .add(new BasicNameValuePair("tableid", id));
                    nameValuePairs.add(new BasicNameValuePair(
                            "totalamount", amountvalue.toString()));
                    nameValuePairs.add(new BasicNameValuePair("itemnames",
                            arr.toString()));
                    nameValuePairs.add(new BasicNameValuePair("price",
                            price.toString()));
                    System.out.println(arr.toString());
                    System.out.println(price.toString());
                    HttpClient httpclient = new DefaultHttpClient();
                    HttpPost httppost = new HttpPost("http://...........");

                    httppost.setEntity(new UrlEncodedFormEntity(
                            nameValuePairs));
                    HttpResponse response = httpclient.execute(httppost);
                    HttpEntity entity = response.getEntity();
                    Toast.makeText(getApplicationContext(),
                            "Saved Sucessfully", Toast.LENGTH_SHORT).show();
                    String responseBody = EntityUtils.toString(response
                            .getEntity());
                    System.out.println("Responce is :: " + responseBody);
                    lv.clearTextFilter();

                } catch (Exception e) {
                    // TODO: handle exception
                    Toast.makeText(getApplicationContext(),
                            "Network Error", 3000).show();
                }
            }
        });
    }
}