How to send a JSON object over Request with Android?

Question

Hi,

I want to send the following JSON text {"Email":"[email protected]","Password":"123456"} to a web service and read the response. I know to how to read JSON. The problem is that the above jason object must be sent in a variable name jason. How can i do this from android? Like creating a request object setting content headers etc.

Answer 1

Android doesn't have special code for sending and receiving HTTP, you can use standard Java code. I'd recommend using the Apache HTTP client, which comes with Android. Here's a snippet of code I used to send an HTTP POST.

I don't understand what sending the object in a variable named "jason" has to do with anything. If you're not sure what exactly the server wants, consider writing a test program to send various strings to the server until you know what format it needs to be in.

import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.params.BasicHttpParams;
import org.apache.http.params.HttpConnectionParams;
import org.apache.http.params.HttpParams;

int TIMEOUT_MILLISEC = 10000;  // = 10 seconds
HttpParams httpParams = new BasicHttpParams();
HttpConnectionParams.setConnectionTimeout(httpParams, TIMEOUT_MILLISEC);
HttpConnectionParams.setSoTimeout(httpParams, TIMEOUT_MILLISEC);
HttpClient client = new DefaultHttpClient(httpParams);

HttpPost request = new HttpPost(serverUrl);
request.setEntity(new ByteArrayEntity(
    postMessage.toString().getBytes("UTF8")));
HttpResponse response = client.execute(request);

Answer 2

Sending a json object from Android is easy if you use Apache HTTP Client. Here's a code sample on how to do it. You should create a new thread for network activities so as not to lock up the UI thread.

protected void sendJson(final String email, final String pwd) {
        Thread t = new Thread(){
        public void run() {
                Looper.prepare(); //For Preparing Message Pool for the child Thread
                HttpClient client = new DefaultHttpClient();
                HttpConnectionParams.setConnectionTimeout(client.getParams(), 10000); //Timeout Limit
                HttpResponse response;
                JSONObject json = new JSONObject();
                try{
                    HttpPost post = new HttpPost(URL);
                    json.put("email", email);
                    json.put("password", pwd);
                    StringEntity se = new StringEntity( "JSON: " + json.toString());  
                    se.setContentEncoding(new BasicHeader(HTTP.CONTENT_TYPE, "application/json"));
                    post.setEntity(se);
                    response = client.execute(post);
                    /*Checking response */
                    if(response!=null){
                        InputStream in = response.getEntity().getContent(); //Get the data in the entity

                }
                catch(Exception e){
                    e.printStackTrace();
                    createDialog("Error", "Cannot Estabilish Connection");
                }
                Looper.loop(); //Loop in the message queue
            }
        };
        t.start();      
    }

You could also use Google Gson to send and retrieve JSON.