将 ArrayList 转换为 JSONArray

我在用ArrayList<HashMap<String,String>>存储我的购物车物品。但我需要将其转换为JSONArray将其发送到数据库。但是当我将它转换为JSONArray the JSONArray看起来像这样：

03-13 11:09:28.842: D/购物车之前(1339): [{image=2130837526, 类别=椅子，数量=1，价格=400，名称=椅子，prodId=34}， {图片=2130837566，类别=镜子，数量=1，价格=3000，名称=La 方达，prodId=35}]

03-13 11:09:28.842：转换为 JSONArray(1339) 后的 D/cart： [“{图片=2130837526，类别=椅子，数量=1，价格=400， 名称=椅子，prodId=34}"，"{image=2130837566，类别=镜子， 数量=1，价格=3000，名称=拉方达，prodId=35}"]

我认为这是错误的。相反，它应该转换为这样的内容：

cartitems=[{"name":"Chair","price":"1001","prodId":"2","category":"Chairs","image":"2130837519","Quantity":"1"},{"name":"Baxton Studio Club Chair","price":"4545","prodId":"5","category":"Chairs","image":"2130837521","Quantity":"1"}]

要转换为的代码JSONArray:

protected String doInBackground(String... args) {
    AddtoCart obj = (AddtoCart) getApplicationContext();
    JSONArray cart = new JSONArray(obj.getCart());
    HashMap<String, String> params = new HashMap<String, String>();
    params.put("username", username);
    params.put("email", email);
    params.put("payment", payment);
    params.put("address", useraddress);
    params.put("contact", contact);
    params.put("city", usercity);
    params.put("cartitems", cart.toString());
    Log.d("params", params.toString());

    JSONObject json = jParser.makeHttpRequest(url_all_products, "POST", params);
    try {
        success = json.getInt("success");
        message = json.getString("message");
    } catch (JSONException e) {
        e.printStackTrace();
    }
    return null;
}

班级举办ArrayList:

public class AddtoCart extends Application {
    private static final String TAG_QUANTITY = "Quantity";
    private static final String TAG_PRICE = "price";
    ArrayList<HashMap<String, String>> cart = new ArrayList<HashMap<String, String>>();

    public void setCart(ArrayList<HashMap<String, String>> data) {
        //cart = data;
        cart.addAll(data);
        Log.d("Items in the cart", String.valueOf(cart));
    }

    public ArrayList<HashMap<String, String>> getCart() {
        return cart;
    }

    public int getSize() {
        return cart.size();
    }

    public void updateCart(ArrayList<HashMap<String, String>> data) {
        cart = data;
        Log.d("UPDATED CART", String.valueOf(cart));
    }

    public void updateQuantity(int index, String quantity) {
        cart.get(index).put(TAG_QUANTITY,quantity);
    }
}

我发现这对我的项目很有帮助：

我的 ArrayList 中的对象

public class ListItem {
    private long _masterId;
    private String _name;
    private long _category;

    public ListItem(long masterId, String name, long category) {
        _masterId = masterId;
        _name = name;
        _category = category;
    }

    public JSONObject getJSONObject() {
        JSONObject obj = new JSONObject();
        try {
            obj.put("Id", _masterId);
            obj.put("Name", _name);
            obj.put("Category", _category);
        } catch (JSONException e) {
            trace("DefaultListItem.toString JSONException: "+e.getMessage());
        }
        return obj;
    }
}

实际换算：

ArrayList<ListItem> myCustomList = ArrayList<ListItem>();
JSONArray jsonArray = new JSONArray();
for (int i=0; i < myCustomList.size(); i++) {
        jsonArray.put(myCustomList.get(i).getJSONObject());
}