Fb request dialog returns nil incorrectly - IOS Facebook - iphone

Question

Thanks for reading!
I'm trying to create a Facebook request to enable the user to invite his friends to the app.
NSDictionary *params = [[NSDictionary alloc] initWithObjectsAndKeys:nil];
[FBWebDialogs
presentRequestsDialogModallyWithSession:nil
message:#"Learn how to make your iOS apps social."
title:#"Test"
parameters:params
handler:^(FBWebDialogResult result, NSURL *resultURL, NSError *error) {
if (error) {
// Error launching the dialog or sending the request.
NSLog(#"Error sending request.");
} else {
if (result == FBWebDialogResultDialogNotCompleted) {
// User clicked the "x" icon
NSLog(#"User canceled request.");
} else {
// Handle the send request callback
NSDictionary *urlParams = [self parseURLParams:[resultURL query]];
if (![urlParams valueForKey:#"request"]) {
// User clicked the Cancel button
NSLog(#"User canceled request.");
} else {
// User clicked the Send button
NSString *requestID = [urlParams valueForKey:#"request"];
NSLog(#"Request ID: %#", requestID);
}
}
}
}];
}
This is pretty much a clean copy of the Facebook docs code. And it works up to a point
The user can choose the friends and the request goes away and gets received by the friends and it shows up as a notification - everything fine so far.
The problem is that when I try to get the response from the "handler" the resultURL is nil and does not contain anything. And after that I get the log message "User canceled request".
Why don't I get anything back? The main reason that I need this is that I need to know which friends the request was sent to.
Thank you for any help!

Answer 1

Seems like you're passing an nil empty session to presentRequestsDialogModallyWithSession
Use FBSession.activeSession instead and check you have enough permissions to run the request (although if not, you would be getting another different error)

Answer 2

I think you are not having a session opened..please try to use this to open the session.
if (!FBSession.activeSession.isOpen) {
// if the session is closed, then we open it here, and establish a handler for state changes
[FBSession openActiveSessionWithReadPermissions:nil
allowLoginUI:YES
completionHandler:^(FBSession *session,
FBSessionState state,
NSError *error) {
}];
}