CODEWITHSUNDEEP
javaandroidjsonwordpress
Jayvijay Gohil
Jayvijay Gohil

Reputation: 53

Wordpress API - How to loop through a JSON Array of objects in Android/Java

I am new to JSON and I am facing hard time looping through the JSONObjects inside the JSONArray for an Android Application that I am building. I would be thankful if posters would givw a brief explanation of the solution as well because I just don't want to copy & paste the code but understand it. Thank You.

API Link: https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/categories

API Output:

[
{
    "id": 5580,
    "count": 5,
    "description": "",
    "link": "https://spoketest.wordpress.com/category/diversions/",
    "name": "Diversions",
    "slug": "diversions",
    "taxonomy": "category",
    "parent": 0,
    "meta": [],
    "_links": {
        "self": [
            {
                "href": "https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/categories/5580"
            }
        ],
        "collection": [
            {
                "href": "https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/categories"
            }
        ],
        "about": [
            {
                "href": "https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/taxonomies/category"
            }
        ],
        "wp:post_type": [
            {
                "href": "https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/posts?categories=5580"
            }
        ],
        "curies": [
            {
                "name": "wp",
                "href": "https://api.w.org/{rel}",
                "templated": true
            }
        ]
    }
},
{
    "id": 9548,
    "count": 5,
    "description": "",
    "link": "https://spoketest.wordpress.com/category/features/",
    "name": "Features",
    "slug": "features",
    "taxonomy": "category",
    "parent": 0,
    "meta": [],
    "_links": {
        "self": [
            {
                "href": "https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/categories/9548"
            }
        ],
        "collection": [
            {
                "href": "https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/categories"
            }
        ],
        "about": [
            {
                "href": "https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/taxonomies/category"
            }
        ],
        "wp:post_type": [
            {
                "href": "https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/posts?categories=9548"
            }
        ],
        "curies": [
            {
                "name": "wp",
                "href": "https://api.w.org/{rel}",
                "templated": true
            }
        ]
    }
},
{
    "id": 103,
    "count": 10,
    "description": "",
    "link": "https://spoketest.wordpress.com/category/news/",
    "name": "News",
    "slug": "news",
    "taxonomy": "category",
    "parent": 0,
    "meta": [],
    "_links": {
        "self": [
            {
                "href": "https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/categories/103"
            }
        ],
        "collection": [
            {
                "href": "https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/categories"
            }
        ],
        "about": [
            {
                "href": "https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/taxonomies/category"
            }
        ],
        "wp:post_type": [
            {
                "href": "https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/posts?categories=103"
            }
        ],
        "curies": [
            {
                "name": "wp",
                "href": "https://api.w.org/{rel}",
                "templated": true
            }
        ]
    }
},
{
    "id": 660,
    "count": 10,
    "description": "",
    "link": "https://spoketest.wordpress.com/category/people/",
    "name": "People",
    "slug": "people",
    "taxonomy": "category",
    "parent": 0,
    "meta": [],
    "_links": {
        "self": [
            {
                "href": "https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/categories/660"
            }
        ],
        "collection": [
            {
                "href": "https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/categories"
            }
        ],
        "about": [
            {
                "href": "https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/taxonomies/category"
            }
        ],
        "wp:post_type": [
            {
                "href": "https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/posts?categories=660"
            }
        ],
        "curies": [
            {
                "name": "wp",
                "href": "https://api.w.org/{rel}",
                "templated": true
            }
        ]
    }
},
{
    "id": 318,
    "count": 10,
    "description": "",
    "link": "https://spoketest.wordpress.com/category/tech/",
    "name": "Tech",
    "slug": "tech",
    "taxonomy": "category",
    "parent": 0,
    "meta": [],
    "_links": {
        "self": [
            {
                "href": "https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/categories/318"
            }
        ],
        "collection": [
            {
                "href": "https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/categories"
            }
        ],
        "about": [
            {
                "href": "https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/taxonomies/category"
            }
        ],
        "wp:post_type": [
            {
                "href": "https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/posts?categories=318"
            }
        ],
        "curies": [
            {
                "name": "wp",
                "href": "https://api.w.org/{rel}",
                "templated": true
            }
        ]
    }
},
{
    "id": 160479,
    "count": 6,
    "description": "",
    "link": "https://spoketest.wordpress.com/category/traction/",
    "name": "Traction",
    "slug": "traction",
    "taxonomy": "category",
    "parent": 0,
    "meta": [],
    "_links": {
        "self": [
            {
                "href": "https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/categories/160479"
            }
        ],
        "collection": [
            {
                "href": "https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/categories"
            }
        ],
        "about": [
            {
                "href": "https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/taxonomies/category"
            }
        ],
        "wp:post_type": [
            {
                "href": "https://public-api.wordpress.com/wp/v2/sites/spoketest.wordpress.com/posts?categories=160479"
            }
        ],
        "curies": [
            {
                "name": "wp",
                "href": "https://api.w.org/{rel}",
                "templated": true
            }
        ]
    }
}
]

My Code:

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

public class Category {
private int mCategoryID;
private String mCategoryName;

public static Category fromJSON(JSONArray jsonArray) {
    try {
        Category category = new Category();
        category.mCategoryID = jsonArray.getJSONObject("0").getInt("id");
        category.mCategoryName = jsonArray.getJSONObject("0").getString("name");

        return category;
    } catch (JSONException e) {
        e.printStackTrace();
        return null;
    }
}

public int getCategoryID() {
    return mCategoryID;
}

public String getCategoryName() {
    return mCategoryName;
}
}

Upvotes: 1

Views: 695

Answers (1)

Elan Hamburger
Elan Hamburger

Reputation: 2177

Once you've retrieved the response from the API (using AsyncTask), take the response text and create a JSONArray. Then you can loop through the array and extract the categories.

public void onApiResponse(String response) {
    // Create a JSONArray from the response
    JSONArray jsonArray = new JSONArray(response);

    // Create a structure to store all of the categories
    List<Category> categories = new ArrayList<Category>();

    // Loop through the array and parse all the categories
    for (int i = 0; i < jsonArray.length(); i++) {
        // Extract the JSONObject from the index
        JSONObject jsonCategory = jsonArray.getJSONObject(i);

        // Add the category to the list
        categories.add(Category.fromJSON(jsonCategory));
    }

    // Do something with your categories...
}

EDIT: I see you hardcoded some values into your fromJSON, so I thought I'd post a corrected version of that as well.

public static Category fromJSON(JSONObject jsonObject) {
    try {
        Category category = new Category();
        category.mCategoryID = jsonObject.getInt("id");
        category.mCategoryName = jsonObjectgetString("name");

        return category;
    } catch (JSONException e) {
        e.printStackTrace();
        return null;
    }
}

Upvotes: 1

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