How to use OKHTTP to make a post request?

Question

I read some examples which are posting jsons to the server.

some one says :

OkHttp is an implementation of the HttpUrlConnection interface p

Answer 1

To add okhttp as a dependency do as follows

• right click on the app on android studio open "module settings"
• "dependencies"-> "add library dependency" -> "com.squareup.okhttp3:okhttp:3.10.0" -> add -> ok..

now you have okhttp as a dependency

Now design a interface as below so we can have the callback to our activity once the network response received.

public interface NetworkCallback {

    public void getResponse(String res);
}

I create a class named NetworkTask so i can use this class to handle all the network requests

    public class NetworkTask extends AsyncTask{

    public NetworkCallback instance;
    public String url ;
    public String json;
    public int task ;
    OkHttpClient client = new OkHttpClient();
    public static final MediaType JSON
            = MediaType.parse("application/json; charset=utf-8");

    public NetworkTask(){

    }

    public NetworkTask(NetworkCallback ins, String url, String json, int task){
        this.instance = ins;
        this.url = url;
        this.json = json;
        this.task = task;
    }


    public String doGetRequest() throws IOException {
        Request request = new Request.Builder()
                .url(url)
                .build();

        Response response = client.newCall(request).execute();
        return response.body().string();
    }

    public String doPostRequest() throws IOException {
        RequestBody body = RequestBody.create(JSON, json);
        Request request = new Request.Builder()
                .url(url)
                .post(body)
                .build();
        Response response = client.newCall(request).execute();
        return response.body().string();
    }

    @Override
    protected String doInBackground(String[] params) {
        try {
            String response = "";
            switch(task){
                case 1 :
                    response = doGetRequest();
                    break;
                case 2:
                    response = doPostRequest();
                    break;

            }
            return response;
        }catch (Exception e){
            e.printStackTrace();
        }
        return null;
    }

    @Override
    protected void onPostExecute(String s) {
        super.onPostExecute(s);
        instance.getResponse(s);
    }
}

now let me show how to get the callback to an activity

    public class MainActivity extends AppCompatActivity implements NetworkCallback{
    String postUrl = "http://your-post-url-goes-here";
    String getUrl = "http://your-get-url-goes-here";
    Button doGetRq;
    Button doPostRq;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Button button = findViewById(R.id.button);

        doGetRq = findViewById(R.id.button2);
    doPostRq = findViewById(R.id.button1);

        doPostRq.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                MainActivity.this.sendPostRq();
            }
        });

        doGetRq.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                MainActivity.this.sendGetRq();
            }
        });
    }

    public void sendPostRq(){
        JSONObject jo = new JSONObject();
        try {
            jo.put("email", "yourmail");
            jo.put("password","password");

        } catch (JSONException e) {
            e.printStackTrace();
        }
    // 2 because post rq is for the case 2
        NetworkTask t = new NetworkTask(this, postUrl,  jo.toString(), 2);
        t.execute(postUrl);
    }

    public void sendGetRq(){

    // 1 because get rq is for the case 1
        NetworkTask t = new NetworkTask(this, getUrl,  jo.toString(), 1);
        t.execute(getUrl);
    }

    @Override
    public void getResponse(String res) {
    // here is the response from NetworkTask class
    System.out.println(res)
    }
}