FBSharebutton always opens sharedialog in webview

Question

i am implementing FBShareButton in my project,but share dialog always opens WebView/Safari View instead of facebook native app.I am using facebook SDK 4.6 & xcode 7..when i use share dialog separately it opens in app, but when i use FBShareButton to open share dialog it always opens in web view..here is my code

-(void)openFacebookDialog
{
FBSDKShareLinkContent *content = [[FBSDKShareLinkContent alloc] init];
  content.contentURL = [NSURL
    URLWithString:@"https://www.facebook.com/FacebookDevelopers"];
  FBSDKShareButton *shareButton = [[FBSDKShareButton alloc] init];
  shareButton.shareContent = content;  
  shareButton.center = self.view.center;
  [self.view addSubview:shareButton];
}