如何在 JSON 對象中獲取 JSON 數組？

Question

這是我的 JSON：

{
    "data": [
        {
            "id": 1,
            "Name": "Choc Cake",
            "Image": "1.jpg",
            "Category": "Meal",
            "Method": "",
            "Ingredients": [
                {
                    "name": "1 Cup Ice"
                },
                {
                    "name": "1 Bag Beans"
                }
            ]
        },
        {
            "id": 2,
            "Name": "Ice Cake",
            "Image": "dfdsfdsfsdfdfdsf.jpg",
            "Category": "Meal",
            "Method": "",
            "Ingredients": [
                {
                    "name": "1 Cup Ice"
                }
            ]
        }
    ]
}

這就是我獲取 id 和 name 的方式，您可以看到這部分在返回非數組值的 JSON 值時工作正常。

//getting whole json string
JSONObject jsonObj = new JSONObject(jsonStr);

//extracting data array from json string
JSONArray ja_data = jsonObj.getJSONArray("data");
int length = jsonObj .length(); 

//loop to get all json objects from data json array
for(int i=0; i<length; i++) 
{
    JSONObject jObj = ja_data.getJSONObject(i);
    Toast.makeText(this, jObj.getString("Name"), Toast.LENGTH_LONG).show();

    // getting inner array Ingredients
    JSONArray ja = jObj.getJSONArray("Ingredients");
    int len = ja.length();


} 

現在我試圖從成分數組中獲取值，但我不確定如何獲取它們？ 這是我迄今為止一直在嘗試的。

//getting whole json string
JSONObject jsonObj = new JSONObject(jsonStr);

//extracting data array from json string
JSONArray ja_data = jsonObj.getJSONArray("data");
int length = jsonObj .length(); 

//loop to get all json objects from data json array
for(int i=0; i<length; i++) 
{
    JSONObject jObj = ja_data.getJSONObject(i);
    Toast.makeText(this, jObj.getString("Name"), Toast.LENGTH_LONG).show();

    // getting inner array Ingredients
    JSONArray ja = jObj.getJSONArray("Ingredients");
    int len = ja.length();

    // getting json objects from Ingredients json array
    for(int j=0; j<len; j++)
    {
        JSONObject json = ja.getJSONObject(j);
        Toast.makeText(this, json.getString("name"), Toast.LENGTH_LONG).show();
    }
} 

但是這樣做是行不通的，我怎樣才能讓它工作？

Answer 1

我想這會幫助你。

JSONObject jsonObj = new JSONObject(jsonStr);

JSONArray ja_data = jsonObj.getJSONArray("data");
int length = jsonObj.length();
for(int i=0; i<length; i++) {
  JSONObject jsonObj = ja_data.getJSONObject(i);
  Toast.makeText(this, jsonObj.getString("Name"), Toast.LENGTH_LONG).show();

  // getting inner array Ingredients
  JSONArray ja = jsonObj.getJSONArray("Ingredients");
  int len = ja.length();

  ArrayList<String> Ingredients_names = new ArrayList<>();
  for(int j=0; j<len; j++) {
    JSONObject json = ja.getJSONObject(j);
    Ingredients_names.add(json.getString("name"));
  }
}

Answer 2

解決了，使用字符串數組列表從成分中獲取名稱。 使用以下代碼：

JSONObject jsonObj = new JSONObject(jsonStr);

//extracting data array from json string
JSONArray ja_data = jsonObj.getJSONArray("data");
int length = ja_data.length();

//loop to get all json objects from data json array
for(int i=0; i<length; i++){
    JSONObject jObj = ja_data.getJSONObject(i);
    Toast.makeText(this, jObj.getString("Name"), Toast.LENGTH_LONG).show();
    // getting inner array Ingredients
    JSONArray ja = jObj.getJSONArray("Ingredients");
    int len = ja.length();
    ArrayList<String> Ingredients_names = new ArrayList<>();
    for(int j=0; j<len; j++){
        JSONObject json = ja.getJSONObject(j);
        Ingredients_names.add(json.getString("name"));
    }
}

Answer 3

JSONObject jsonObject =new JSONObject(jsonStr);
JSONArray jsonArray = jsonObject.getJSONArray("data");
for(int i=0;i<jsonArray.length;i++){
    JSONObject json = jsonArray.getJSONObject(i);
    String id = json.getString("id");
    String name=json.getString("name");
    JSONArray ingArray = json.getJSONArray("Ingredients") // here you are going   to get ingredients
    for(int j=0;j<ingArray.length;j++){
        JSONObject ingredObject= ingArray.getJSONObject(j);
        String ingName = ingredObject.getString("name");//so you are going to get   ingredient name
        Log.e("name",ingName); // you will get 
   }
}

Answer 4

JSONObject jsonObj = new JSONObject(jsonString);

JSONArray jArray = jsonObj.getJSONArray("data");
int length = jArray.length();

   for(int i=0; i<length; i++)
      {
        JSONObject jObj = jArray.getJSONObject(i);
        String id = jObj.optString("id");
        String name=jObj.optString("name");

        JSONArray ingredientArray = jObj.getJSONArray("Ingredients");
        int size = ingredientArray.length();
        ArrayList<String> Ingredients = new ArrayList<>();

            for(int j=0; j<size; j++)
               {
                    JSONObject json = ja.getJSONObject(j);
                    Ingredients.add(json.optString("name"));
                }


       }

Answer 5

你的int length = jsonObj.length(); 應該是int length = ja_data.length();

Answer 6

  Gson gson = new Gson();
                Type listType = new TypeToken<List<Data>>() {}.getType();
                List<Data>     cartProductList = gson.fromJson(response.body().get("data"), listType);
                Toast.makeText(getContext(), ""+cartProductList.get(0).getCity(), Toast.LENGTH_SHORT).show();