XCode 4 - 通用应用程序 - 使用标签栏控制器时视图不会改变

Question

我还是新手，所以请耐心等待：

我在 XCode 4 中创建了一个新的基于 Window 的应用程序，它恰好是一个通用应用程序。之后，我以编程方式创建了一个带有关联视图控制器的 TabBarController（只是带有 1-2 个标签的基本视图，以帮助我识别每个版本（iPad、iPhone）。

当我运行应用程序并切换选项卡时，viewDidLoad 方法会触发，标题正确显示，但视觉视图没有切换。它保留在每个版本的默认 MainWindow(device).xib 文件中。我在这里错过了什么？

以编程方式添加选项卡：

- (void) addTabs
{
//set up a local nav controller which we will reuse for each view controller
UINavigationController *localNavigationController;

//create tab bar controller and array to hold the view controllers
tabBarController = [[UITabBarController alloc] init];
NSMutableArray *localControllersArray = [[NSMutableArray alloc] initWithCapacity:2];

//setup the first view controller (Root view controller)
HomeViewController *myViewController;
myViewController = [[HomeViewController alloc] init];

//create the nav controller and add the root view controller as its first view
localNavigationController = [[UINavigationController alloc] initWithRootViewController:myViewController];

// add the new nav controller (with the root view inside of it)
// to the array of controllers
[localControllersArray addObject:localNavigationController];

//release
[localNavigationController release];
[myViewController release];    

//setup the second view controller
MapViewController *secondViewController;
secondViewController = [[MapViewController alloc] initWithTabBar];

localNavigationController = [[UINavigationController alloc] initWithRootViewController:secondViewController];

[localControllersArray addObject:localNavigationController];
[localNavigationController release];
[secondViewController release];

tabBarController.viewControllers = localControllersArray;
[localControllersArray release];

 }

而且 MapViewController.h 是基本的 - 那里真的什么都没有：

#import "MapViewController.h"

@implementation MapViewController

- (id)initWithTabBar {
if ([self init]) {
    //this is the label of the tab button itself
    self.title = @"Map";

    //image goes here
    //self.tabBarItem.image = [UIImage imageNamed:@"name_gray.png"];

    //set the long name show in the Navigation bar at the top
    self.navigationItem.title = @"Map View";

}

return self;
}

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
    // Custom initialization
}
return self;
}

- (void)didReceiveMemoryWarning
{
// Releases the view if it doesn't have a superview.
[super didReceiveMemoryWarning];

// Release any cached data, images, etc that aren't in use.
}




// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad
{
[super viewDidLoad];
   NSLog(@"Am I loading?");
}


- (void)viewDidUnload
   {
[super viewDidUnload];
// Release any retained subviews of the main view.
// e.g. self.myOutlet = nil;
  }

- (void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
NSLog(@"Testing");
}

- (void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:animated];
}

- (void)viewWillDisappear:(BOOL)animated
{
   [super viewWillDisappear:animated];
}

- (void)viewDidDisappear:(BOOL)animated
{
   [super viewDidDisappear:animated];
}


- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
   // Return YES for supported orientations
   return (interfaceOrientation == UIInterfaceOrientationPortrait);
}

@end

现在，没有 MapViewController.xib 文件，只有 MapViewController_iPhone.xib 和 MapViewController_iPad.xib 文件。

Answer 1

它们应该命名为：~iphone 和 ~ipad，而不是：_iPhone 和 _iPad。原因是这是reference 所说的格式。

另外请注意，模拟器不区分大小写，而 iOS 设备是，因此请确保您的笔尖按上述格式格式化，否则，它只能在模拟器上工作。

希望有帮助！