Get array elements in JSON

Further works on the former exercise "Parse JSON with JSONObject", array elements are added in the dummy JSON.



Modify res/values/strings.xml to add array in dummy JSON string.

<?xml version="1.0" encoding="utf-8"?>
<resources>
   <string name="hello">Hello World, AndroidJSONActivity!</string>
   <string name="app_name">AndroidJSON</string>
   <string name="dummy_json">"{\"results\":{\"myblog\":\"android-er\", \"myurl\":"\""http://android-er.blogspot.com/\",\"array\":[{\"element\":\"Element 1\"}, {\"element\":\"Element 2\"}, {\"element\":\"Element 3\"}]"}}"</string>
</resources>

Modify main.xml to add a TextView "json_myarray" to display the array elements.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:orientation="vertical"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  >
<TextView
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  android:text="@string/hello"
  />
<TextView
  android:id="@+id/json_src"
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  />
<TextView
  android:id="@+id/json_object"
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  />
<TextView
  android:id="@+id/json_result"
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  />
<TextView
  android:id="@+id/json_myblog"
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  />
<TextView
  android:id="@+id/json_myurl"
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  />
<TextView
  android:id="@+id/json_myarray"
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  />
</LinearLayout>

Modify the code, to retrieve array elements from JSON.

package com.exercise.AndroidJSON;

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

import android.app.Activity;
import android.os.Bundle;
import android.widget.TextView;
import android.widget.Toast;

public class AndroidJSONActivity extends Activity {

  /** Called when the activity is first created. */
  @Override
  public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.main);
    
      TextView JsonSrc = (TextView)findViewById(R.id.json_src);
      TextView JsonObject = (TextView)findViewById(R.id.json_object);
      TextView JsonResult = (TextView)findViewById(R.id.json_result);
      TextView JsonMyBlog = (TextView)findViewById(R.id.json_myblog);
      TextView JsonMyUrl = (TextView)findViewById(R.id.json_myurl);
      TextView JsonMyArray = (TextView)findViewById(R.id.json_myarray);
    
      String json_source = getString(R.string.dummy_json);
      JsonSrc.setText(json_source);
    
      try {
  JSONObject jsonObject = new JSONObject(json_source);
  JSONObject results = jsonObject.getJSONObject("results");
  String myBlog = results.getString("myblog");
  String myUrl = results.getString("myurl");
 
  JsonObject.setText("\njsonObject:\n" + jsonObject.toString());
  JsonResult.setText("\nresults:\n" + results.toString());
        JsonMyBlog.setText("\nmyBlog:\n" + myBlog);
        JsonMyUrl.setText("\nmyUrl:\n" + myUrl);
      
        //Retrieve Array Elements in JSON
        String stringArrayElement = "\n";
        JSONArray jsonArray = results.getJSONArray("array");
        for (int i = 0; i < jsonArray.length(); i++) {
         JSONObject arrayElement = jsonArray.getJSONObject(i);
         stringArrayElement += arrayElement.getString("element") + "\n";
        }
      
        JsonMyArray.setText(stringArrayElement);
 
 } catch (JSONException e) {
  // TODO Auto-generated catch block
  e.printStackTrace();
  Toast.makeText(AndroidJSONActivity.this,
    e.toString(),
    Toast.LENGTH_LONG).show();
 }
  }
}

Download the files.

Related article:
- Another example to parse JSON