How to do multiple serial connection using nsurlconnection? - objective-c

Question

i am new to iPhone development so i don't know whether this is simple or complicated.
Here is my problem. I have a app which first connects to web service for authentication process. After authentication i need to get data of logged in user. So, how to connect to web services twice and serially using NSURLConnection. Serially means first login and then retrieve data. In my case, the request are sent in random order, means sometime it sends login request first and some time retrieve data request.
Can anyone please help this out.
Thanks.

Answer 1

Set the delegate of your NSURLConnection to self, and implement NSURLConnectionDelegate methods, there's a method named
- (void) connectionDidFinishLoading:(NSURLConnection*)connection
which tells you when the request was finished successfully so inside it you can call the second request.
Now your only problem is that you don't know which request to call second :) as you don't know which one was called first so what I usually do is simply, define some variable, simply an int or NSString as a tag, e.g.
Add these before your #implemenetation
#define TAG_LOGIN_REQUEST 1
#define TAG_DATA_REQUEST 2
now define this inside the class
int currentTag
now before you start the login request add this
currentTag = TAG_LOGIN_REQUEST;
and before you start the data request add this
currentTag = TAG_DATA_REQUEST;
whenever this delegate method gets called
- (void) connectionDidFinishLoading:(NSURLConnection*)connection
you simply check
if (tag == TAG_LOGIN_REQUEST) {
// send data request
}
else if (tag == TAG_DATA_REQUEST) {
// send login request
}
I hope this helps, if there's anything that's not clear, please tell me.

Answer 2

Just try to synchronise you calling. Here is a example:
request for login and wait for login response
get login response and call getData()
if login response if yes, request for data.
Hope this helps.. :)
EDIT:
maintain two global flag (variable). let loginReq and dataReq are those flag.
before calling getLogin(), make loginReq = true;
in your connectinDidFinishLoading check
if(loginReq == true){
loginReq = false;
dataReq = true;
getData();
}
else if(dataReq == true){
dataReq = false;
}