Android Read Jsonarray Into A Jsonarray

How can i read a json array that contains a json array this is my json { 'product': { 'name': 'myApp', 'config': [ { 'grade': 'eleme

Solution 1:

Well first, this is not a JSONArray; it's a JSONObject. A JSONArray is denoted by opening and closes braces ([ and ], respectively), while a JSONObject is denoted by opening/closing brackets ({ and }, respectively).

Now, to answer your question as to how to parse it...

Let's assume you have:

Strings= your_json_data;

Now, to parse that:

JSONObject jsonObj = newJSONObject(s);

JSONObject productJson = jsonObject.getJSONObject("product"); // May want to consider using optJSONObject for null checking in case your key/value combination doesn't existString name = productJson.getString("name"); // myApp

Now that should get you started with the basic stuff... Let's go over iterating through an actual JSONArray:

JSONArray configJsonArray = productJson.getJSONArray("config");
for(int configIterator = 0; configIterator < configJsonArray.length(); configIterator++){
    JSONObject innerConfigObj = configJsonArray.getJSONObject(configIterator);
    String configGrade = innerConfigObj.getString("grade");

    JSONArray courseJsonArray = innerConfigObj.getJSONArray("courses");
    for(int courseIterator = 0; courseIterator < courseJsonArray.length(); courseIterator++){
        JSONObject innerCourseObj = innerCourseObj.getJSONObject(courseIterator);
        String courseName = innerCourseObj.getString("name");
        String courseTeacher = innerCourseObj.getString("teacher");
    }
}

That should allow you to iterate through them.

Solution 2:

Here is an example of how you would parse it using gson - https://code.google.com/p/google-gson/. It really makes life a lot easier, you create your class structure once and then just reuse it throughout your application.

package com.example.jsonparse;

import java.util.List;

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;

import com.google.gson.Gson;

publicclassMainActivityextendsActivity {

    privatestatic final StringTAG = MainActivity.class.getSimpleName();

    @OverrideprotectedvoidonCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        final String json = "{\"product\": {\"name\": \"myApp\",\"config\": [{\"grade\": \"elementary school\",\"courses\": [{\"name\": \"Math\",\"teacher\": \"David\"}]}]}}";

        JsonParseResult result = newGson().fromJson(json, JsonParseResult.class);

        for (Config config : result.getProduct().getConfig()) {

            Log.d(TAG, "Courses for grade: " + config.getGrade());

            for (Course course : config.getCourses()) {
                Log.d(TAG, "Course Name: " + course.getName());
                Log.d(TAG, "Course Teacher: " + course.getTeacher());
            }
        }
    }

    publicclassJsonParseResult {

        privateProduct product;

        publicJsonParseResult(Product product) {
            this.product = product;
        }

        publicProductgetProduct() {
            return product;
        }

        publicvoidsetProduct(Product product) {
            this.product = product;
        }
    }

    publicclassProduct {

        privateString name;
        privateList<Config> config;

        publicProduct(String name, List<Config> config) {
            this.name = name;
            this.config = config;
        }

        publicStringgetName() {
            return name;
        }

        publicvoidsetName(String name) {
            this.name = name;
        }

        publicList<Config> getConfig() {
            return config;
        }

        publicvoidsetConfig(List<Config> config) {
            this.config = config;
        }

    }

    publicclassConfig {

        privateString grade;
        privateList<Course> courses;

        publicConfig(String grade, List<Course> courses) {
            this.grade = grade;
            this.courses = courses;
        }

        publicStringgetGrade() {
            return grade;
        }

        publicvoidsetGrade(String grade) {
            this.grade = grade;
        }

        publicList<Course> getCourses() {
            return courses;
        }

        publicvoidsetCourses(List<Course> courses) {
            this.courses = courses;
        }

    }

    publicclassCourse {

        privateString name;
        privateString teacher;

        publicCourse(String name, String teacher) {
            this.name = name;
            this.teacher = teacher;
        }

        publicStringgetName() {
            return name;
        }

        publicvoidsetName(String name) {
            this.name = name;
        }

        publicStringgetTeacher() {
            return teacher;
        }

        publicvoidsetTeacher(String teacher) {
            this.teacher = teacher;
        }
    }
}