Sharing on Facebook, Twitter and Google+

[FIXED]     Font of navbar.
[FIXED]     A few compile fixes.
[IMPROVED]  Made properties nonatomic.
[ADDED]     Support for facebook, twitter and google+ sharing.

External/google-plus-ios-sdk/SampleCode/GooglePlusSampleSignInViewController.h

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+//
+//  GooglePlusSignInViewController.h
+//
+//  Copyright 2012 Google Inc.
+//
+//  Licensed under the Apache License, Version 2.0 (the "License");
+//  you may not use this file except in compliance with the License.
+//  You may obtain a copy of the License at
+//
+//  http://www.apache.org/licenses/LICENSE-2.0
+//
+//  Unless required by applicable law or agreed to in writing, software
+//  distributed under the License is distributed on an "AS IS" BASIS,
+//  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+//  See the License for the specific language governing permissions and
+//  limitations under the License.
+//
+
+#import <UIKit/UIKit.h>
+#import "GooglePlusSignIn.h"
+
+@class GooglePlusSignInButton;
+
+// A view controller for the Google+ sign-in button which initiates a standard
+// OAuth 2.0 flow and provides an access token and a refresh token. A "Sign out"
+// button is provided to allow users to sign out of this application.
+@interface GooglePlusSampleSignInViewController : UIViewController<
+    GooglePlusSignInDelegate>
+
+// The button that handles Google+ sign-in.
+@property (retain, nonatomic) IBOutlet GooglePlusSignInButton *signInButton;
+// A label to display the result of the sign-in action.
+@property (retain, nonatomic) IBOutlet UILabel *signInAuthStatus;
+// A button to sign out of this application.
+@property (retain, nonatomic) IBOutlet UIButton *signOutButton;
+
+// Called when the user presses the "Sign out" button.
+- (IBAction)signOut:(id)sender;
+
+@end