How can I call what I have in Static Method from MainActivity in Android

Issue

I have this class and a problem with the simple Static {} method:

 package com.example.tabletapp1.dummy;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.os.StrictMode;
import android.util.Log;

public class DummyContent {

    public static List<DummyItem> ITEMS = new ArrayList<DummyItem>();
    public static Map<String, DummyItem> ITEM_MAP = new HashMap<String, DummyItem>();
    public static ArrayList<HashMap<String, String>> stireList = new ArrayList<HashMap<String, String>>();

    static {   /////// THIS FUNCTION
        StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder()
                .permitAll().build();

        StrictMode.setThreadPolicy(policy);

        String url = "http://kosalis.beclenar.ro/stiri.txt";

        // JSON Node names
        String TAG_STIRE = "stire";
        String TAG_ID = "ID";
        String TAG_NUME = "Nume";
        String TAG_DESCRIERE = "Descriere";
        String TAG_POZA = "Poza";
        String TAG_CORP_STIRE_HTML = "Corp_stire_html";

        // contacts JSONArray
        JSONArray news = null;

        // Creating JSON Parser instance
        JSONParser jParser = new JSONParser();

        // getting JSON string from URL
        JSONObject json = jParser.getJSONFromUrl(url);

        try {
            // Getting Array of Contacts
            news = json.getJSONArray(TAG_STIRE);

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

                // Storing each json item in variable
                String id = c.getString(TAG_ID);
                String name = c.getString(TAG_NUME);
                String description = c.getString(TAG_DESCRIERE);
                String poza = c.getString(TAG_POZA);
                String body_html = c.getString(TAG_CORP_STIRE_HTML);

                // creating new HashMap
                HashMap<String, String> map = new HashMap<String, String>();

                // adding each child node to HashMap key => value
                map.put(TAG_ID, id);
                map.put(TAG_NUME, name);
                map.put(TAG_DESCRIERE, description);
                map.put(TAG_POZA, poza);

                // adding HashList to ArrayList
                stireList.add(map);
                addItem(new DummyItem(id, name, description, poza, body_html));

            }
        } catch (JSONException e) {
            Log.e("Error2", TAG_CORP_STIRE_HTML);
            e.printStackTrace();
        }
    }

    private static void addItem(DummyItem item) {
        ITEMS.add(item);
        ITEM_MAP.put(item.id, item);
    }

    public static class DummyItem {
        public String id;
        public String title;
        public String description;
        public String content;
        public String photo;

        public DummyItem(String id, String title, String description,
                String photo, String content) {
            this.id = id;
            this.title = title;
            this.description = description;
            this.photo = photo;
            this.content = content;
        }

        @Override
        public String toString() {
            return title;
        }
    }
}

But I have no Idea how to do what is in the static { } function from MainActivity. I would like to call an asynctask from my mainactivity because every time my app starts, the UI freezes, and I'm sure it's because of that static functions which creates a JSONPArser class:

    package com.example.tabletapp1.dummy;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONException;
import org.json.JSONObject;

import android.util.Log;

public class JSONParser {

    static InputStream is = null;
    static JSONObject jObj = null;
    static String json = "";

    // constructor
    public JSONParser() {
    }

    public JSONObject getJSONFromUrl(String url) {
        // Making HTTP request
        try {
            // defaultHttpClient
            DefaultHttpClient httpClient = new DefaultHttpClient();
            HttpGet httpGet = new HttpGet(url);
            HttpResponse httpResponse = httpClient.execute(httpGet);
            HttpEntity httpEntity = httpResponse.getEntity();
            is = httpEntity.getContent();

        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        try {
            BufferedReader reader = new BufferedReader(new InputStreamReader(
                    is, "ISO-8859-2"), 8);
            StringBuilder sb = new StringBuilder();
            String line = null;
            while ((line = reader.readLine()) != null) {
                sb.append(line + "\n");
            }
            is.close();
            json = sb.toString();
        } catch (Exception e) {
            Log.e("Buffer Error", "Error converting result " + e.toString());
        }

        // try parse the string to a JSON object
        try {
            jObj = new JSONObject(json);
        } catch (JSONException e) {
            Log.e("JSON Parser", "Error parsing data " + e.toString());
        }
        // return JSON String
        return jObj;
    }
}

And I have another question: Lets say I have a AsyncTask, and in doInBackground() I call the JSONParser class, is that going to freeze the UI or not?

Solution

You'll want to replace static { with static void staticMethod() {. Then you can call it with DummyContent.staticMethod().

edit: @Mah makes a good point about the multiple questions. Please let me know if you create a new one and I can move part of my answer to it for you.

As for Asynctask, it is indeed good for jobs like these since anything done in doInBackground() will not block the UI thread. For me there was somewhat of a learning curve with it but I've found it to be a very useful class. To use the example below you would call new myAsyncTask().execute(url)

class myAsyncTask extends AsyncTask<String, Integer, Boolean> {

    @Override
    protected Boolean doInBackground(String... url) {
        // This will receive the String you passed into it and return a boolean to onPostExecute()
        // Put all your CPU intensive stuff here

        // publishProgress can be used update the UI thread
        Integer progress = 1;
        publishProgress(progress);

        return true;
    }

    @Override
    protected void onProgressUpdate(Integer... doInBackgroundResult) {
        super.onProgressUpdate(doInBackgroundResult);
        // Anything done here can update the UI but will block
    }

    @Override
    protected void onPostExecute(Boolean doInBackgroundResult) {
        super.onPostExecute(doInBackgroundResult);
        // Runs after doInBackground finishes
        // Anything done here will block the UI
    }
}

Answered By - Jon