Ошибка данных массива Json в Android и не удается найти или получить данные из индекса массива json

Question

Дорогие друзья , я хочу получить значение данных массива json из индекса и сравнить с моим идентификатором магазина.Например:

я хочу получить instituteID из массива json и сравнить со значением «3», а если оно истинно, отобразить сохраненное значение темы в textview if (instituteID == 3) {tv.setText (subject);} instituteID и тема также приходят от json. Скажите, где я не прав

ArrayList<HashMap<String,String>> arraylist = new ArrayList<>();

protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        tv1 = (TextView)findViewById(R.id.subject1);
        tv2 = (TextView)findViewById(R.id.subject2);
        tv3 = (TextView)findViewById(R.id.subject3);
        tv4 = (TextView)findViewById(R.id.subject4);
        tv5 = (TextView)findViewById(R.id.subject5);
        tv6 = (TextView)findViewById(R.id.subject6);

//here calling json asynctask
new getTacherJson().execute();
        DisplayData();
}

public void DisplayData(){
        SharedPreferences preferences = getSharedPreferences("Email's response",MODE_PRIVATE);
        shared_pref_emal = preferences.getString("response",null);
        Log.e("Email's response",shared_pref_emal);

        SharedPreferences preferences1 = getSharedPreferences("Institute's ID",MODE_PRIVATE);
        shared_pref_ins_id = preferences1.getString("response id",null);
        Log.e("inst. id",shared_pref_ins_id);

        if (institute_ID == shared_pref_ins_id){
            tv1.setText(subject);
            tv2.setText(subject2);
            tv3.setText(subject3);
            tv4.setVisibility(View.GONE);
            tv5.setVisibility(View.GONE);
            tv6.setVisibility(View.GONE);
        }
        else {
            tv1.setText("Nothing");
        }
    }

//here is my Json Data
{"response":[{"id":"11","class":"One Class","section":"Morning","teacher":"abc@gmail.com","subject":"Urdu","fromTime":"08:00","toTime":"08:30","instituteID":"3","created_at":"2019-09-12 04:39:31"},{"id":"12","class":"One Class","section":"Morning","teacher":"abc@gmail.com","subject":"Pakistan Studies","fromTime":"08:30","toTime":"09:00","instituteID":"3","created_at":"2019-09-12 04:39:49"},{"id":"13","class":"BSSE","section":"Evening","teacher":"abc@gmail.com","subject":"Introduction to CMP","fromTime":"15:00","toTime":"17:30","instituteID":"3","created_at":"2019-09-16 07:39:43"}]}


MyHttpHandler myhttp = new MyHttpHandler();
            String teacherURL = url+"/showTeacherCourses/"+get_email+"/"+shared_pref_ins_id;
            String teachDash = myhttp.MyServiceCall(teacherURL);
            Log.e(TAG,"Response From Teacher Courses"+teachDash);

        if (teachDash != null) {
            try {
                JSONObject jsonObject = new JSONObject(teachDash);
                JSONArray teachArray = jsonObject.getJSONArray("response");
                Log.e("Array length", String.valueOf(teachArray.length()));

                // looping through All Contacts
                for (int i = 0; i < teachArray.length(); i++) {
                    JSONObject c = teachArray.getJSONObject(i);

                    id1 = c.getString("id");
                    clasx = c.getString("class");
                    section = c.getString("section");
                    teacher_emaill = c.getString("teacher");
                    subject = c.getString("subject");
                    from_time = c.getString("fromTime");
                    to_time = c.getString("toTime");
                    institute_ID = c.getString("instituteID");
                    created_at = c.getString("created_at");


HashMap<String, String> tech_dta_ftch = new HashMap<>();

                        // adding each child node to HashMap key => value

                        tech_dta_ftch.put("id", id1);
                        tech_dta_ftch.put("class",clasx);
                        tech_dta_ftch.put("section",section);
                        tech_dta_ftch.put("teacher",teacher_emaill);
                        tech_dta_ftch.put("subject",subject);
                        tech_dta_ftch.put("fromTime",from_time);
                        tech_dta_ftch.put("toTime",to_time);
                        tech_dta_ftch.put("created_at", created_at);
                        tech_dta_ftch.put("instituteID", institute_ID);

                        // adding contact to contact list
                        arraylist.add(tech_dta_ftch);

Answer 1

Попробуйте это:

for(int i = 0; i < teachArray.length(); i++){
    JSONObject c = teachArray.getJSONObject(i);
    HashMap<String, String> tech_dta_ftch = new HashMap<>();
    tech_dta_ftch.put("id", c.getString("id"));
    tech_dta_ftch.put("class",c.getString("class"));
    tech_dta_ftch.put("section",c.getString("section"));
    tech_dta_ftch.put("teacher",c.getString("teacher"));
    tech_dta_ftch.put("subject",c.getString("subject"));
    tech_dta_ftch.put("fromTime",c.getString("fromTime"));
    tech_dta_ftch.put("toTime",c.getString("toTime"));
    tech_dta_ftch.put("created_at", c.getString("created_at"));
    tech_dta_ftch.put("instituteID", c.getString("instituteID"));
    arraylist.add(tech_dta_ftch);   
}

И для сравнения идентификатора института по определенному индексу вашего списка массивов, который я сейчас выбираю по первому индексу, вы можете использовать его, вероятно, по-своему:

if (arraylist.get(0).get("instituteID").equalsIgnoreCase("ID_TO_CHECK_WITH")){
    //DO YOUR STUFF
}