Question

我正在尝试创建一个购物车应用程序，一切都很好，但现在我被困在最后三天在stackoverflow搜索批次但无法得到答案。我正在从服务器填充listview，有两个按钮在每行加（用于添加数量）和减去（减少它）。这是我向购物车添加数量的屏幕。我试图在单击两个按钮之一时向sqlite数据库插入行，我已经实现了这一点，我在listview中的下一个活动中显示这些数据。这里我的问题开始时，我插入数据，它正确显示它，但在更新期间，它显示奇怪的行为。如果我点击前三行插入和更新工作正常，但如果我向下滚动并点击任何项目，而不是每次插入时更新..我知道这个问题是相当大和冗长但我找不到一个好方法总结一下对不起..请帮帮我...

这是我作为输出获得的屏幕。

这是我的ListView类。

public class MyFragment extends Fragment implements View.OnClickListener{

int mCurrentPage;
private ListView listView;
RecyclerView recyclerView;
private FeedListAdapter listAdapter;
private List<FeedItem> feedItems;
private ProgressDialog pDialog;
private List<FeedItem> productsInCart = new ArrayList<FeedItem>();
private RelativeLayout content;
private SharedPreferences preference;
TextView badge,prices;
int totalCount=0,newCount = 0;
int lastCount;
int totalPrice;
SQLiteDatabase dataBase;
public static final String TOTAL_COUNT = "count";
DBHelper mHelper;
boolean isUpdate;
String userId,price,pname,position;
private Button checkOut;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    /** Getting the arguments to the Bundle object */
    Bundle data = getArguments();

    /** Getting integer data of the key current_page from the bundle */
    mCurrentPage = data.getInt("current_page", 0);

}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    View v = inflater.inflate(R.layout.myfragment_layout, container, false);

       recyclerView= (RecyclerView) v.findViewById(R.id.my_recycler_view);
       content  = (RelativeLayout)v.findViewById(R.id.content);
       badge = (TextView)v.findViewById(R.id.all_comments);
       checkOut = (Button)v.findViewById(R.id.checkOut);
       prices = (TextView)v.findViewById(R.id.price);
        feedItems = new ArrayList<FeedItem>();
        new JSONAsyncTask()
        .execute("http://api.androidhive.info/feed/feed.json");
        listAdapter = new FeedListAdapter(getActivity(), feedItems);
         recyclerView.setAdapter(listAdapter);
         recyclerView.setHasFixedSize(true);
         recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
        pDialog = new ProgressDialog(getActivity());
        pDialog.setMessage("Please wait...");
        pDialog.setCancelable(true);
        listAdapter.setOnAddNum(this);
        listAdapter.setOnSubNum(this);
        mHelper=new DBHelper(getActivity());

        content.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View arg0) {
                // TODO Auto-generated method stub
                Intent i = new Intent(getActivity(),CheckOutFooter.class);
                startActivity(i);
                getActivity().overridePendingTransition
                (R.anim.slide_in_bottom, R.anim.slide_out_bottom);
            }
        });

        checkOut.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View arg0) {
                // TODO Auto-generated method stub

                if (userId != null){

                    Intent i = new Intent(getActivity(),CheckOut.class);
                    startActivity(i);
                }

                else{

                    Toast.makeText(getActivity(), "Cart is empty! Please add few products to cart.",
                            Toast.LENGTH_SHORT).show();
                }

            }
       });



    return v;
}

    // TODO Auto-generated method stub



class JSONAsyncTask extends AsyncTask<String, Void, Boolean> {

        @Override
        protected void onPreExecute() {
        super.onPreExecute();
         }

        @Override
        protected Boolean doInBackground(String... urls) {
        try {
            //------------------>>
            HttpGet httppost = new HttpGet(urls[0]);
            HttpClient httpclient = new DefaultHttpClient();
            HttpResponse response = httpclient.execute(httppost);

            // StatusLine stat = response.getStatusLine();
            int status = response.getStatusLine().getStatusCode();

            if (status == 200) {
                HttpEntity entity = response.getEntity();
                String data = EntityUtils.toString(entity);


                JSONObject jsono = new JSONObject(data);
                JSONArray jarray = jsono.getJSONArray("feed");

                for (int i = 0; i < jarray.length(); i++) {
                    JSONObject feedObj = jarray.getJSONObject(i);

                  //  Actors actor = new Actors();
                    FeedItem item = new FeedItem();
                    item.setObservation(feedObj.optString("name"));
                    item.setSummary(feedObj.optString("timeStamp"));
                    item.setName(feedObj.optString("name"));

                    feedItems.add(item);

                }
                return true;
            }

            //------------------>>

        } catch (ParseException e1) {
            e1.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } catch (JSONException e) {
            e.printStackTrace();
        }
        return false;
    }

    protected void onPostExecute(Boolean result) {

        if(result == false){
            Toast.makeText(getActivity(), "Unable to fetch data from server", Toast.LENGTH_LONG).show();
    }
        else{

            listAdapter.notifyDataSetChanged();
           }

        pDialog.dismiss();
        }
      }

 @Override
 public void onClick(View view) {
     Object tag = (Integer) view.getTag();
     switch (view.getId()){
         case R.id.btnAddToCart1:

            // FeedItem item = feedItems.get(tag);
             if (tag != null && tag instanceof Integer) {

                 int position = (Integer) tag;


    int   num =feedItems.get(position).getNum();
      int price =feedItems.get(position).getPrice();
      String pName = feedItems.get(position).getName();
      String product_name = feedItems.get(position).getName(); 
      num++;
      feedItems.get(position).setNum(num);
      feedItems.get(position).setPrice(position);

      Toast.makeText(getActivity(),
              product_name+ " is added to cart!", Toast.LENGTH_SHORT).show();

      preference = getActivity().getSharedPreferences("STATE", Context.MODE_PRIVATE);
      preference.edit().putString("QUANTITY", String.valueOf(num)).apply();
      preference.edit().putString("PRICE", String.valueOf(num*position)).apply();
      preference.edit().putString("PNAME",product_name).apply();
      preference.edit().putString("POSITION",String.valueOf(position)).apply();
      updateData();
      listAdapter.notifyDataSetChanged();

             }
     break;

   case R.id.btnAddToCart5:
       if (tag != null && tag instanceof Integer) {

           int position = (Integer) tag;
           int num =feedItems.get(position).getNum();
           int price =feedItems.get(position).getPrice();
       if (num>0) {
           num--;
           feedItems.get(position).setNum(num);
           feedItems.get(position).setPrice(position);
           preference = getActivity().getSharedPreferences("STATE", Context.MODE_PRIVATE);
           preference.edit().putString("QUANTITY", String.valueOf(num)).apply();
           preference.edit().putString("PRICE", String.valueOf(num*position)).apply();
           preference.edit().putString("POSITION",String.valueOf(position)).apply();
          updateData();
           listAdapter.notifyDataSetChanged();

       }

       else{
            num= 0;

            dataBase.delete(
                    DBHelper.TABLE_NAME,
                    DBHelper.KEY_ID + "="
                            + (position+1), null);
            listAdapter.notifyDataSetChanged();
        }

       }



       break;
     }
 }


public void onResume(){
     super.onResume();

 }

private void updateData() {

    preference = 
            getActivity().getSharedPreferences("STATE", Context.MODE_PRIVATE);

    userId = preference.getString("QUANTITY", null);
    price = preference.getString("PRICE", null);
    pname = preference.getString("PNAME", null);
    position = preference.getString("POSITION", null);

    int counts = Integer.parseInt(position);



    if(userId == null){

        badge.setText("0");

    }
    else{
     checkOut.setEnabled(true);

    badge.setText(String.valueOf(userId));



     dataBase = mHelper.getReadableDatabase();

     /*Cursor curs = dataBase.rawQuery("SELECT SUM(price) FROM cart", null);
        if(curs.moveToFirst())
        {

            int total = curs.getInt(0);

            System.out.println("Total Sum of Price : "+total);
            prices.setText(String.valueOf(total)+" Rs/-");

        }
    */
     Cursor  cur = null;
     String query = "SELECT * FROM " + DBHelper.TABLE_NAME +
          " WHERE " +DBHelper.KEY_ID+"=?;" ;




        cur = dataBase.rawQuery(query,new String[] {String.valueOf(counts+1)});

       if((cur != null) && (cur.getCount() > 0)){
           dataBase = mHelper.getWritableDatabase();
         ContentValues cv = new ContentValues();
         cv.put(DBHelper.KEY_COUNT,userId);
         cv.put(DBHelper.KEY_PRICE, price);
         cv.put(DBHelper.KEY_PNAME, pname);
         System.out.println("Database values : "+cv);
         dataBase.update(DBHelper.TABLE_NAME, cv, DBHelper.KEY_ID+" = '" +
                                        String.valueOf(counts+1) + "'", null);
         cur.close();
       }
       else{
         dataBase = mHelper.getWritableDatabase();
         ContentValues cv = new ContentValues();
         cv.put(DBHelper.KEY_COUNT,userId);
         cv.put(DBHelper.KEY_PRICE, price);
         cv.put(DBHelper.KEY_PNAME, pname);
         System.out.println("Database values : "+cv);
         dataBase.insert(DBHelper.TABLE_NAME, null, cv);
         cur.close();
       }

    }

}

}

我的结帐页面显示sqlite的数据。

  public class CheckOut  extends AppCompatActivity{

    private ArrayList<String> userId = new ArrayList<String>();
    private ArrayList<String> product_Name = new ArrayList<String>();
    private ArrayList<String> product_Quantity = new ArrayList<String>();
    private ArrayList<String> product_Price = new ArrayList<String>();
    private ArrayList<Integer> quantityList = new ArrayList<Integer>();
    private ArrayList<Integer> amountList = new ArrayList<Integer>();

    ListView recyclerView;
    TextView quantity;
    TextView amount;
    Button pay;
    DBHelper mHelper;
    SQLiteDatabase dataBase;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    setContentView(R.layout.checkout);

    recyclerView= (ListView) findViewById(R.id.my_recycler_view);
    amount = (TextView) findViewById(R.id.amount);
    quantity = (TextView) findViewById(R.id.quantity);
    pay = (Button) findViewById(R.id.pay);
    mHelper = new DBHelper(this);


}


@Override
protected void onResume() {
    displayData();
    super.onResume();
}


private void displayData() {
    dataBase = mHelper.getWritableDatabase();
    Cursor mCursor = dataBase.rawQuery("SELECT * FROM " + DBHelper.TABLE_NAME, null);
    int sum = 0;
    int qty = 0;
    userId.clear();
    product_Name.clear();
    product_Quantity.clear();
    quantityList.clear();
    amountList.clear();
    product_Price.clear();
    if (mCursor.moveToFirst()) {
        do {
            userId.add(mCursor.getString(mCursor.getColumnIndex(DBHelper.KEY_ID)));
            product_Name.add(mCursor.getString(mCursor.getColumnIndex(DBHelper.KEY_PNAME)));
            product_Quantity.add(mCursor.getString(mCursor.getColumnIndex(DBHelper.KEY_COUNT)));
            product_Price.add(mCursor.getString(mCursor.getColumnIndex(DBHelper.KEY_PRICE)));

        } while (mCursor.moveToNext());
    }
    DisplayAdapter disadpt = new DisplayAdapter(CheckOut.this,userId, product_Name, product_Price,product_Quantity);
    recyclerView.setAdapter(disadpt);
    mCursor.close();

    quantityList = convertInteger(product_Quantity);
    amountList = converAmountInteger(product_Price);

    for (int i : quantityList){

        qty = qty+i;
    }

    for (int s : amountList){

        sum = sum +s;
    }
    amount.setText(String.valueOf(sum));
    quantity.setText(String.valueOf(qty));

    disadpt.notifyDataSetChanged();
}


private ArrayList<Integer> converAmountInteger(
        ArrayList<String> product_Price2) {
    // TODO Auto-generated method stub
     ArrayList<Integer> result = new ArrayList<Integer>();
     for(String amount : product_Price2) {
            try {
                //Convert String to Integer, and store it into integer array list.
                result.add(Integer.parseInt(amount));
            } catch(NumberFormatException nfe) {
               //System.out.println("Could not parse " + nfe);
                Log.w("NumberFormat", "Parsing failed! " + amount + " can not be an integer");
            } 
        }       
        return result;
}


private ArrayList<Integer> convertInteger(
        ArrayList<String> product_Quantity2) {
    // TODO Auto-generated method stub
     ArrayList<Integer> result = new ArrayList<Integer>();
     for(String quantity : product_Quantity2) {
            try {
                //Convert String to Integer, and store it into integer array list.
                result.add(Integer.parseInt(quantity));
            } catch(NumberFormatException nfe) {
               //System.out.println("Could not parse " + nfe);
                Log.w("NumberFormat", "Parsing failed! " + quantity + " can not be an integer");
            } 
        }       
        return result;


}

数据库类：

public class DBHelper extends SQLiteOpenHelper {

public static String DATABASE_NAME="user.db";
public static final String TABLE_NAME="cart";
public static final String KEY_COUNT="cartItem";
public static final String KEY_PNAME="product_name";
public static final String KEY_ID="id";
public static final String KEY_PRICE="price";
public static final String KEY_CREATED_AT="created_at";


public DBHelper(Context context) {
    super(context, DATABASE_NAME, null, 1);

}
@Override
public void onCreate(SQLiteDatabase db) {
    String CREATE_TABLE="CREATE TABLE "+TABLE_NAME+" ("+KEY_ID+" INTEGER PRIMARY KEY, "+KEY_COUNT+" INTEGER,"
                                                       +KEY_PNAME+" TEXT,"+KEY_PRICE+" INTEGER,"+ KEY_CREATED_AT
                                                       + " DATETIME" + ")";
    db.execSQL(CREATE_TABLE);

}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    db.execSQL("DROP TABLE IF EXISTS "+TABLE_NAME);
    onCreate(db);

}

更新： 有一点错误我改变了列名而不是我创建了一个唯一的密钥，它的工作正常......

使用sqlite自定义listview的奇怪行为

0 个答案: