Facebook iOS SDK 4.1.0 Share Callback - ios

Question

Using the FBSDK mentioned in the title of this question, I present a simple share dialog in a view controller:
// Setup the content for the share
FBSDKShareLinkContent *content = [[FBSDKShareLinkContent alloc] init];
content.contentURL = linkUrl;
content.contentDescription = description;
content.contentTitle = title;
content.imageURL = imageUrl;
// Show the share dialog
[FBSDKShareDialog showFromViewController:controller
withContent:content
delegate:someDelegate];
And implement the delegate method...
- (void)sharer:(id<FBSDKSharing>)sharer didCompleteWithResults:(NSDictionary *)results
{
NSLog(#"Sweet, they shared.");
}
So far so good, as long as the user has the Facebook application installed on their device. The issue arises when the user does not have Facebook installed. If this is the case, Safari opens up to a web version of Facebook's login flow (this is fine), but if you then switch back to the original application without logging into Facebook / performing any additional tasks, the completion delegate method shown above is called.
Does anyone have any experience with a workaround for this? It seems like there should be a reliable way for determining whether or not the post did indeed occur.
Note: The above code is pretty pseudo-ish. In the actual implementation I have indeed implemented all of the delegate call backs (didComplete, didCancel, and didFail).

Answer 1

Edit: It turns out, the results dictionary is empty when the completion method is called if the Facebook app is installed on the device. To overcome this, a check needs to be done to see if Facebook is installed first.
Of course after posting I stumbled upon the answer. The results dictionary returned in the didCompleteWithResults method contains a postId key if the share actually occurred. So the logic is as simple as:
- (void)sharer:(id<FBSDKSharing>)sharer didCompleteWithResults:(NSDictionary *)results
{
NSURL *fbURL = [NSURL URLWithString:#"fb://"];
if (![[UIApplication sharedApplication] canOpenURL:fbURL])
if (results[#"postId"]) {
NSLog(#"Sweet, they shared, and Facebook isn't installed.");
} else {
NSLog(#"The post didn't complete, they probably switched back to the app");
}
} else {
NSLog(#"Sweet, they shared, and Facebook is installed.");
}
}
Although this works, it doesn't seem to be a very safe way of going about things (what if Facebook changes the key from "postId" to something else in the future? Unlikely but you get my point).