Get data from a web server in Objective C - iphone

Question

I have a very convenient way of getting data from a web server in my Android app, and would like to be able to duplicate that method for iOS.
In Android I have a Async Class that I call from other classes and it returns data from server when it has finished loading.
This is how that class looks like:
public class GetData extends AsyncTask, String, Void> {
public Context context;
InputStream is = null;
StringBuilder sb = null;
public GetData (Context context) {
this.context = context;
}
#Override
/**
* Send the values in params to the server
*/
protected Void doInBackground(ArrayList<NameValuePair>... params) {
String server = "mywebpage";
HttpPost httppost=new HttpPost(server);
HttpClient httpclient=new DefaultHttpClient();
try {
httppost.setEntity(new UrlEncodedFormEntity(params[0]));
HttpResponse rs=httpclient.execute(httppost);
HttpEntity entity = rs.getEntity();
is = entity.getContent();
try{
BufferedReader reader = new BufferedReader(new InputStreamReader(is,"UTF-8"),8);
sb = new StringBuilder();
sb.append(reader.readLine());
String line = "0";
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
}
catch(Exception e) {
Log.e("log_tag", "Error converting result "+e.toString());
}
is.close();
publishProgress(sb.toString());
}catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
}catch (IOException e) {
e.printStackTrace();
}
return null;
}
}
If I want to use the GetData class I create a new instance of it like so:
new GetData(this.getActivity()) {
#Override
protected void onProgressUpdate(String... string) {
result = string[0]);
}
}.execute(data);
I have been able to get and send data from within each viewController in iOS but I haven't been able to get a similar method to this one to work.
I have been trying to create a Class but I'm not sure how to call it with certain parameters and what subclass I should make GetData be of.
Is there any good way to do this in Objective C?

Answer 1

I would suggest looking into the commonly used AFNetworking library. Here is an example of how to do a post:
AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];
NSDictionary *parameters = #{#"foo": #"bar"};
[manager POST:#"http://example.com/resources.json" parameters:parameters success:^(AFHTTPRequestOperation *operation, id responseObject) {
NSLog(#"JSON: %#", responseObject);
} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
NSLog(#"Error: %#", error);
}];
Also, though I have not used it yet, it looks like you can use AFURLSessionManager to update progress in upload and download tasks.

Answer 2

Here is how you make a connection without using a third party library:
Creating a Connection