Developing a user interface on iOS environment using GoogleMaps APIv3 - iphone

Question

I'm new to iOS development. Today, I created a new "SingleViewApplication". I added new Navigation Bars using storyboarding.
Next, I followed the tutorial https://developers.google.com/maps/documentation/ios/start to integrate Google Maps into my project.
However, after adding GoogleMaps, my Navigation Bar has disappeared. Somehow, Google Maps override the interface constructed by using storyboard.
Any suggestions, tutorials, information is kindly appreciated.
The codes are given below:
shareAppDelegate.h
#import <UIKit/UIKit.h>
#interface shareAppDelegate : UIResponder <UIApplicationDelegate>
#property (strong, nonatomic) UIWindow *window;
#end
shareAppDelegate.m
//
// shareAppDelegate.m
// share
//
// Created by neva on 9/17/13.
// Copyright (c) 2013 neva. All rights reserved.
//
#import "shareAppDelegate.h"
#import <GoogleMaps/GoogleMaps.h>
#implementation shareAppDelegate
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
[GMSServices provideAPIKey:#"AIzaSyDqbi8tp0DeUHQKASyRyJUqJbOZpMOuuig"];
// Override point for customization after application launch.
return YES;
}
- (void)applicationWillResignActive:(UIApplication *)application
{
// Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state.
// Use this method to pause ongoing tasks, disable timers, and throttle down OpenGL ES frame rates. Games should use this method to pause the game.
}
- (void)applicationDidEnterBackground:(UIApplication *)application
{
// Use this method to release shared resources, save user data, invalidate timers, and store enough application state information to restore your application to its current state in case it is terminated later.
// If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits.
}
- (void)applicationWillEnterForeground:(UIApplication *)application
{
// Called as part of the transition from the background to the inactive state; here you can undo many of the changes made on entering the background.
}
- (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.
}
- (void)applicationWillTerminate:(UIApplication *)application
{
// Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.
}
#end
ShareViewController.h
//
// shareViewController.h
// share
//
// Created by neva on 9/17/13.
// Copyright (c) 2013 neva. All rights reserved.
//
#import <UIKit/UIKit.h>
#interface shareViewController : UIViewController
#end
ShareViewController.m
//
// shareViewController.m
// share
//
// Created by neva on 9/17/13.
// Copyright (c) 2013 neva. All rights reserved.
//
#import "shareViewController.h"
#import <GoogleMaps/GoogleMaps.h>
#interface shareViewController ()
#end
#implementation shareViewController{
GMSMapView *mapView_;
}
- (void)loadView {
// Create a GMSCameraPosition that tells the map to display the
// coordinate -33.86,151.20 at zoom level 6.
GMSCameraPosition *camera = [GMSCameraPosition cameraWithLatitude:-33.86
longitude:151.20
zoom:6];
mapView_ = [GMSMapView mapWithFrame:CGRectZero camera:camera];
mapView_.myLocationEnabled = YES;
self.view = mapView_;
// Creates a marker in the center of the map.
GMSMarker *marker = [[GMSMarker alloc] init];
marker.position = CLLocationCoordinate2DMake(-33.86, 151.20);
marker.title = #"Sydney";
marker.snippet = #"Australia";
marker.map = mapView_;
}
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
#end