UIActivityViewController - is there a way to know which activity was selected?

Id like to be able to track if the user shared by facebook, twitter, etc, but it seems there's no way to know which method was selected. Is there?

You can use Activity Types in setCompletionHandler

UIActivityViewController *activityVC = [[UIActivityViewController alloc]initWithActivityItems:activityItems applicationActivities:nil];

[activityVC setCompletionHandler:^(NSString *activityType, BOOL completed) {
    if([activityType isEqualToString: UIActivityTypeMail]){
        NSLog(@"Mail");
    }
    if([activityType isEqualToString: UIActivityTypePostToFacebook]){
        NSLog(@"Facebook");
    }

}];
[self presentViewController:activityVC animated:TRUE completion:nil];

Built-in activity types for which the system has built-in support for.

NSString *const UIActivityTypePostToFacebook;

NSString *const UIActivityTypePostToTwitter;

NSString *const UIActivityTypePostToWeibo;

NSString *const UIActivityTypeMessage;

NSString *const UIActivityTypeMail;

NSString *const UIActivityTypePrint;

NSString *const UIActivityTypeCopyToPasteboard;

NSString *const UIActivityTypeAssignToContact;

NSString *const UIActivityTypeSaveToCameraRoll;

Edited for iOS 8

Please note that this will generate a compiler warning in iOS 8, you need to use the setCompletionWithItemsHandler method instead of the setCompletionHandler method.

Replace:

[activityVC setCompletionHandler:^(NSString *activityType, BOOL completed) {

with:

[activityVC setCompletionWithItemsHandler:^(NSString *activityType, BOOL completed,  NSArray *returnedItems, NSError *activityError) {

In Swift 4:

activityViewController.completionWithItemsHandler = { activity, success, items, error in
        if !success{
            print("cancelled")
            return
        }

        if activity == .postToTwitter {
            print("twitter")
        }

        if activity == .mail {
            print("mail")
        }
    }

swift 3

let activityViewController:UIActivityViewController = UIActivityViewController(activityItems: [screenCapture], applicationActivities: nil)
activityViewController.excludedActivityTypes = [UIActivityType.print, UIActivityType.postToWeibo, UIActivityType.copyToPasteboard, UIActivityType.addToReadingList, UIActivityType.postToVimeo]

activityViewController.completionWithItemsHandler = { activity, success, items, error in
    if !success{
        print("cancelled")
        return
    }

    if activity == UIActivityType.postToFacebook {
        print("facebook")
    }

    if activity == UIActivityType.mail {
        print("mail")
    }

}

self.present(activityViewController, animated: true, completion: nil)

You can use this lib https://github.com/rdougan/RDActivityViewController to identify which activity has been touched and return custom data by activity just by implementing its protocol.

Like This:

- (NSArray *)activityViewController:(NSArray *)activityViewController itemsForActivityType:(NSString *)activityType
{
    if ([activityType isEqualToString:UIActivityTypePostToTwitter]) {
        return @[@"Twitter text"];
    } else if ([activityType isEqualToString:UIActivityTypeMessage]) {
        return @[@"Message text"];
    } else if ([activityType isEqualToString:UIActivityTypeMail]) {
        return @[@"Mail text"];
    } else if ([activityType isEqualToString:UIActivityTypePostToFacebook]) {
        return @[@"Facebook text"];
    } else {
        return @[@"Default text"];
    }
}

I hope I have helped you!