Android convert JSONArray to String Array

Question

I get data from Json and there's a Json array. I want to convert that Json array into String array, so I can send it into another activity and show it in ListView.

Here's My java code

 if (jsonStr != null) {
 try {
 foodsFilter = new JSONArray(jsonStr);
 // looping through All Contacts
 for (int i = 0; i < foodsFilter.length(); i++) {
 JSONObject c = foodsFilter.getJSONObject(i);
 if(c.getString("category_name").equals("Food")) {
 String category_name = c.getString(TAG_CATEGORY_NAME);
 String filter_type = c.getString(TAG_FILTER_TYPE);
 //String item_list = c.getString(TAG_ITEM_LIST);
 JSONArray itemList = new JSONArray(c.getString("item_list"));
 String item_list = itemList.toString();
 // tmp hashmap for single contact
 HashMap<String, String> filter = new HashMap<String, String>();
 // adding each child node to HashMap key => value
 filter.put(TAG_CATEGORY_NAME, category_name);
 filter.put(TAG_FILTER_TYPE, filter_type);
 filter.put(TAG_ITEM_LIST, item_list);
 // adding contact to contact list
 foodsFilterList.add(filter);
 }
 }
 } catch (JSONException e) {
 e.printStackTrace();
 }
 }

I try that code to convert the JSONarray, but I realized that code is for convert the JSONArray into String.

Here's my JSON data

[{"category_name":"Food","filter_type":"Sort by","field_name":"","type":"VALUE","table_name":"","item_list":["Ascending","Descending"]}]

I want to convert the item_list Array into like this

item_list = {"Ascending", "Descending"}

So I can send it into another activity use Intent and show it in ListView

• Leonardo: Why not simply do this on the listview activity itself? Passing stuff using Intent is an expensive operation
• Matthew: Because I already have a listview on that activity. And I want to show that Data in another activity :D
• Raghunandan: @Matthew you can still parse the json in the listview activity itself.
• Matthew: @Raghunandan Do you mean, show the data on the same activity?
• Raghunandan: @Matthew you could show in the same activity or parse the data in Activity that has listview. passing through intent is expensive operation. If you can avoid it good

Answer 1

What you have

String item_list = itemList.toString();

You need to parse items_list which is a JSONArray.

JSONArray itemList = new JSONArray(c.getString("item_list"));
// loop through the array itemList and get the items
for(int i=0;i<itemList.length();i++) 
{ 
String item = itemList.getString(i); // item at index i
}

Now you can add the strings to a list/array and then do what is required.

• Matthew: What If I have a dinamic data? Not just Ascend and Descend?
• Raghunandan: @Matthew you still be looping through the array from 0 to end of array and use the index to get the items required
• Matthew: there's an error on String item = itemsList.getString(i); // item at index i that the itemList variable cannot be resolved.
• Raghunandan: @Matthew where do you have that piece of code?. itemList is JSONArray itemList = new JSONArray(c.getString("item_list"));
• Matthew: Thanks for your help. Its done. I really appreciate it

Answer 2

Please have a look on this tutorial.

http://www.androidhive.info/2012/01/android-json-parsing-tutorial/

Maybe this would help you.

ArrayList<String> stringArray = new ArrayList<String>();
JSONArray jsonArray = new JSONArray();
for(int i = 0, count = jsonArray.length(); i< count; i++)
{
 try {
 JSONObject jsonObject = jsonArray.getJSONObject(i);
 stringArray.add(jsonObject.toString());
 }
 catch (JSONException e) {
 e.printStackTrace();
 }
}