I have programmatically created a second view controller (MySecondViewController) which was all done and hooked up without using the visual object editor.
My problem is that when I run the app, only the original view controller (HelloWorldViewController) comes up; the second view controller does not show up. When I click on the view for HelloWorldViewController, nothing comes up.
Can you tell me what's wrong?
windowBasedAppAppDelegate.h
#import <UIKit/UIKit.h>
//-- Add a forward reference to the HelloWorldViewController class --
@class HelloWorldViewController;
@interface windowBasedAppAppDelegate : NSObject <UIApplicationDelegate> {
//-- create an instance of the view controller--
HelloWorldViewController *viewController;
}
@property (nonatomic, retain) IBOutlet UIWindow *window;
//--Expose the view controller as a property--
@property (nonatomic, retain) IBOutlet HelloWorldViewController *viewController;
@end
windowBasedAppAppDelegate.m
#import "windowBasedAppAppDelegate.h"
#import "HelloWorldViewController.h"
#import "MySecondViewController.h"
@implementation windowBasedAppAppDelegate
@synthesize window;
@synthesize viewController;
//-- a second view controller object--
MySecondViewController *mySecondViewController;
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
// Override point for customization after application launch.
//-- add the new view to the current window--
//-- instantiate the second view controller --
mySecondViewController = [[MySecondViewController alloc]
initWithNibName:nil
bundle:nil];
// -- add the view from the second controller --
//[window addSubview:mySecondViewController.view];
[window addSubview:viewController.view];
[self.window makeKeyAndVisible];
return YES;
}
- (void)dealloc
{
[MySecondViewController release];
[viewController release];
[window release];
[super dealloc];
}
@end
MySecondViewController.h
#import <UIKit/UIKit.h>
@interface MySecondViewController : UIViewController {
//-- create two outlets, label and button --
UILabel *label;
UIButton *button;
}
//-- expose the outlets as properties --
@property (nonatomic, retain) UILabel *label;
@property (nonatomic, retain) UIButton *button;
// -- declaring the IBAction ---
- (IBAction) buttonClicked: (id)sender;
@end
MySecondViewController.h
#import "MySecondViewController.h"
@implementation MySecondViewController
@synthesize label, button;
- (IBAction) buttonClicked: (id)sender {
UIAlertView *alert =
[[UIAlertView alloc] initWithTitle:@"Action Invoked!" message:@"Button clicked" delegate:self cancelButtonTitle:@"OK" otherButtonTitles: nil];
[alert show];
[alert release];
}
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
// Custom initialization
}
return self;
}
- (void)dealloc
{
[super dealloc];
}
HelloWorldViewController.h
#import <UIKit/UIKit.h>
@interface HelloWorldViewController : UIViewController {
}
@end
HelloWorldViewController.m
@implementation HelloWorldViewController
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
// Custom initialization
}
return self;
}
- (void)dealloc
{
[super dealloc];
}
Added code from MySecondViewController.m
//-- add the views to the view window --
[self.view addSubview:label];
[self.view addSubview:button];
[view exchangeSubviewAtIndex:1 withSubviewAtIndex:0];
self.view = view;
[super viewDidLoad];
Since the view
is being initialized and that it has a proper frame, the problem could be this sequence of code,
[window addSubview:mySecondViewController.view];
[window addSubview:viewController.view];
As the viewController
's view
will have the same frame, it will be added over mySecondViewController
's view
. So you will have to remove the second line for the view to show up.
You never actually push the new view controller onto the screen.
mySecondViewController = [[MySecondViewController alloc]
initWithNibName:nil
bundle:nil];
// -- add the view from the second controller --
//[window addSubview:mySecondViewController.view];
[window addSubview:viewController.view];
You add viewController.view, (which should be undefined...), but not mySecondViewController.view.
Also, programHasFinishedLaunching may not be the best possible place to push it. If I were you, I'd put a button on the front page that pushes the new view in, it's easier that way.
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