Calling FBSession.activeSession as instructed to in tutorial, results in NSException - iphone

Question

I am trying to enable Facebook login in my iphone app.
I am following the instructions on this page:
https://developers.facebook.com/docs/howtos/login-with-facebook-using-ios-sdk/#step4
I have followed the instructions in Step #4 (Logging in to Facebook), but my code crashes when I run it.
This is my method that is causing the crash:
- (void)applicationDidBecomeActive:(UIApplication *)application
{
// Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface.
// We need to properly handle activation of the application with regards to Facebook Login
// (e.g., returning from iOS 6.0 Login Dialog or from fast app switching).
NSLog(#"here 1");
NSLog(#"active session: %#",FBSession.activeSession);
[FBSession.activeSession handleDidBecomeActive];
NSLog(#"here 2");
}
And here is my stack trace at the time of the crash (app name replaced with XXX):
2013-02-11 17:31:17.956 TRIO[9426:907] here 1
* thread #1: tid = 0x2503, 0x324d9960 libobjc.A.dylib`objc_exception_throw, stop reason = breakpoint 1.1
frame #0: 0x324d9960 libobjc.A.dylib`objc_exception_throw
frame #1: 0x3161af98 CoreFoundation`-[NSException raise] + 8
frame #2: 0x0009f7cc XXX`-[FBSession initWithAppID:permissions:defaultAudience:urlSchemeSuffix:tokenCacheStrategy:] + 240 at FBSession.m:236
frame #3: 0x0009f6d6 XXX`-[FBSession initWithAppID:permissions:urlSchemeSuffix:tokenCacheStrategy:] + 46 at FBSession.m:208
frame #4: 0x0009f680 XXX`-[FBSession init] + 32 at FBSession.m:191
frame #5: 0x000a061a XXX`+[FBSession activeSession] + 62 at FBSession.m:568
frame #6: 0x00073c4e XXX`-[AppDelegate applicationDidBecomeActive:] + 66 at AppDelegate.m:118
frame #7: 0x38e3bae2 UIKit`-[UIApplication _stopDeactivatingForReason:] + 342
frame #8: 0x38e219b8 UIKit`-[UIApplication _runWithURL:payload:launchOrientation:statusBarStyle:statusBarHidden:] + 1072
frame #9: 0x38dc9c38 UIKit`-[UIApplication handleEvent:withNewEvent:] + 1004
frame #10: 0x38dc96cc UIKit`-[UIApplication sendEvent:] + 72
frame #11: 0x38dc911a UIKit`_UIApplicationHandleEvent + 6154
frame #12: 0x393605a2 GraphicsServices`_PurpleEventCallback + 590
frame #13: 0x393601d2 GraphicsServices`PurpleEventCallback + 34
frame #14: 0x315f0172 CoreFoundation`__CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 34
frame #15: 0x315f0116 CoreFoundation`__CFRunLoopDoSource1 + 138
frame #16: 0x315eef98 CoreFoundation`__CFRunLoopRun + 1384
frame #17: 0x31561ebc CoreFoundation`CFRunLoopRunSpecific + 356
frame #18: 0x31561d48 CoreFoundation`CFRunLoopRunInMode + 104
frame #19: 0x38e2047c UIKit`-[UIApplication _run] + 668
frame #20: 0x38e1d2f8 UIKit`UIApplicationMain + 1120
frame #21: 0x00073748 XXX`main + 96 at main.m:16
When I run the Facebook sample code, they work fine, and I believe I've added all the required frameworks.
Thanks.

Answer 1

I had the same error as above and it was because I did not add my own FacebookAppID along with the "URL types" key to my project's info.plist