swift - Facebook login for iOS error: The operation couldn’t be completed. (com.facebook.sdk.core error 3.) -

i'm receiving error code:

the operation couldn’t completed. (com.facebook.sdk.core error 3.) 

for logging facebook on app , not sure why. here viewcontroller code:

import fbsdkcorekit import fbsdkloginkit  @iboutlet weak var facebookloginbutton: fbsdkloginbutton!     override func viewdidload() {     super.viewdidload()    facebookloginbutton.readpermissions = ["public_profile", "email", "user_friends"]     facebookloginbutton.delegate = self    }    //mark: facebook login    func loginbutton(loginbutton: fbsdkloginbutton!, didcompletewithresult result: fbsdkloginmanagerloginresult!, error: nserror!) {     if error == nil {        print("login complete")        performseguewithidentifier("facebooksegue", sender: self)      } else {        print(error.localizeddescription)      }   }    func loginbuttondidlogout(loginbutton: fbsdkloginbutton!) {     print("user logged out")   } 

here appdelegate:

import fbsdkcorekit      func application(application: uiapplication, didfinishlaunchingwithoptions launchoptions: [nsobject: anyobject]?) -> bool {         // override point customization after application launch.        //facebook login         return fbsdkapplicationdelegate.sharedinstance().application(application, didfinishlaunchingwithoptions: launchoptions)     }    func application(application: uiapplication, openurl url: nsurl, sourceapplication: string?, annotation: anyobject) -> bool {      //facebook login     return fbsdkapplicationdelegate.sharedinstance().application(application, openurl: url, sourceapplication: sourceapplication, annotation: annotation)   } 

i think code correct maybe i'm missing something, appreciated!

was able figure out. plist file had modified followed:

<key>lsapplicationqueriesschemes</key>     <array>       <string>fb</string>       <string>fbapi</string>       <string>fbauth2</string>       <string>fbshareextension</string>       <string>fb-messenger-api</string>     </array> 

after adding worked!