ArrayList being empty after adding elements

Question

I have this android code which bring a JSON from a server and fill an ArrayList from that JSON I checked the size of the ArrayList \"meals\" inside the onresponse void it gi

Answer 1

The problem here is about understanding how asynchronous tasks work. When you are adding a volley request to the queque, it will run in background thread (off the main thread) and control will pass to the next line.

So, after this:

Volley.newRequestQueue(getActivity()).add(mealsrequest);

control passes to this:

ArrayList strs=new ArrayList();
String mealsnames[]=new String[meals.size()];

Now since meals is updated on the background thread, you are not able to get the data by the time control reaches String mealsnames[]=new String[meals.size()];

So you will get zero size (meals.size()) here.

Try to move this portion of the code into onResponse.

Try like this:

public void updateData(){
   ArrayList strs=new ArrayList();
   String mealsnames[]=new String[meals.size()];
   for(int i=0;i

and call this method from onResponse:

@Override
public void onResponse(String response) {
    try{
        JSONObject object= new JSONObject(response);
        JSONArray mealsArray = object.getJSONArray("result");
        for(int i=0;i