java如何使用截取方法获取ArrayList

Question

这是我需要获取的ArrayList的示例，如何获取这个数组？我正在使用截取方法获取这个数组并显示在回收器视图中

[ { "_id": "a2a1", "name": "Flower", "image": { "_id": "a2a2", "name": "flower.jpg", "url": "/uploads/c8c8c.jpg", "related": [ "a2a1" ], "id": "0a2a2" }, }, { "_id": "433d", "name": "Bouquet", "id": "433d", "image": { "_id": "433e", "name": "baloon.jpg", "url": "/uploads/247db.jpg", "related": [ "433d" ], "id": "433e" }, }]

这是我使用截取方法获取数组的代码，我已经输入了正确的api，但是我没有得到数组的列表

  private void FlowerList(){

    StringRequest request = new StringRequest(
            Request.Method.GET,
            ServerApi.URL_FLOWER,

            new Response.Listener<String>() {
                @Override
                public void onResponse(String response) {
                    Gson gson = new GsonBuilder().create();


                    if(response != null) {

                        JSONObject json = null;

                        try {
                            json = new JSONObject(response);
                            FlowerModel[] models = gson.fromJson(String.valueOf(json.getJSONArray(null)), FlowerModel[].class);
                            flowerAdapter.addBatch(Arrays.asList(models));


                        } catch (JSONException e) {
                            e.printStackTrace();
                        }
                    }
                }
            },

            new Response.ErrorListener() {
                @Override
                public void onErrorResponse(VolleyError error) {

                }
            }

    );

    Volley.newRequestQueue(getContext()).add(request);

}

Answer 1

试试这个。。。。我修改了你的密码

ArrayList<String> stringArrayList;
String id1,name,id2;

StringRequest request = new StringRequest(
        Request.Method.GET,
        ServerApi.URL_FLOWER,

        new Response.Listener<String>() {
            @Override
            public void onResponse(String response) {
                Gson gson = new GsonBuilder().create();


                if(response != null) {

                    JSONObject json = null;

                    try {
                        json = new JSONObject(response);
                        JSONArray jsonArray=json.getJSONArray("Your_response_arrayName");
                        stringArrayList=new ArrayList<>();
                        for(i=0;i<jsonArray.length;i++){
                            JSONObject jsonObject=jsonArray.getJSONObject(i);
                            stringArrayList.add(jsonObject);


                        }


                    } catch (JSONException e) {
                        e.printStackTrace();
                    }
                }
            }
        },

        new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError error) {

            }
        }

);

Volley.newRequestQueue(getContext()).add(request);

}

希望这对你有帮助

Answer 2

如果您使用的是Gson verson 2.8'，则

try {
                            json = new JSONObject(response);
                           ArrayList<FlowerModel> models = gson.fromJson(response, TypeToken.getParameterized(ArrayList.class, FlowerModel.class).getType());
                            //flowerAdapter.addBatch(Arrays.asList(models));


                        } catch (JSONException e) {
                            e.printStackTrace();
                        }

对于旧版本

 try {
                                json = new JSONObject(response);
                               ArrayList<FlowerModel> models = gson.fromJson(response, new TypeToken<ArrayList<FlowerModel>>(){}.getType(););
                                //flowerAdapter.addBatch(Arrays.asList(models));


                            } catch (JSONException e) {
                                e.printStackTrace();
                            }