how to get jsonobject form volley onResponse library - android-volley

Question

I'm an android beginner and I want to make a login using volley library, but i don't
know how i can obtain the JSONObject response from my server and use it to check
login parameters and launch a specific activity if the user exist.

Answer 1

//assuming you are implementing this part from an activity.
//otherwise, replace “this” with relevant context
RequestQueue myQueue = queue = Volley.newRequestQueue(this);
//your server address
String url = "http://my-json-feed";
//Create your JSON object request
JsonObjectRequest jsObjRequest = new JsonObjectRequest
(Request.Method.GET, url, null, new Response.Listener() {
#Override
public void onResponse(JSONObject response) {
//process the server response here.
//use the “response” object for checking the login parameters, etc.
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
//Handle errors such as network failures,etc here
}
});
//add the request object to the Volley queue
myQueue.add(jsObjRequest);
The "onResponse()" is the callback function which will give you the json object returned by the server. Inside that function, use that response to do whatever you want (for your case, to check login parameters, etc.)
For details, look here: Request JSON
Another note:
If you are to use the VolleyQueue only in one or two activities, it's okay to create separate volley queues for those couple of activities. But, if you have lots of activities and all of them needs to use Volley, then it would be a very bad choice to create volley queues for each activity. It can cause you OutOfMemory exception in the worst case. You can consider creating a singleton VolleyQueue which will be used by the whole application (Creating an ApplicationController class and including the Volley singleton queue in it can be one way to do that).