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For Iphone how to reference root view controller from currently loaded view, so view can be replaced/switched

I'm trying to switch a currently loaded view with a new one.

I have 3 xib files and 3 sets of ViewControllerFiles.

RootViewController loads correctly, and correctly loads HomeViewController.

The line that errors currently is this

[self.rootViewController.view insertSubview:gameController.view atIndex:1];

**error: request for member 'view' in something not a structure or a union**

If anyone could point me in the right direction that would be great. I understand how I could switch views all from the root controller but I want to swap/add views from a subview. If that makes sense?

Here is the root controller header and implementation:

#import <UIKit/UIKit.h>

@class HomeViewController;
@class GameViewController;

@interface RootViewController : UIViewController {
    HomeViewController *homeViewController;
    GameViewController *gameViewController;
}

@property (retain, nonatomic) HomeViewController *homeViewController;
@property (retain, nonatomic) GameViewController *gameViewController;

- (IBAction)showHome:(id)sender;
- (IBAction)showGame:(id)sender;

@end

Implemenation file:

#import "RootViewController.h"
#import "HomeViewController.h"
#import "GameViewController.h"

@implementation RootViewController

@synthesize homeViewController;
@synthesize gameViewController;

- (void)viewDidLoad {
    homeViewController.rootViewController = self;

    HomeViewController *homeController = [[HomeViewController alloc]    initWithNibName:@"HomeView" bundle:nil];
    self.homeViewController = homeController;   
    [self.view insertSubview:homeController.view atIndex:0];    
    [homeController release];   

    [super viewDidLoad];
}

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

    if (self.homeViewController.view.superview == nil) {
        self.homeViewController = nil;
    } else {
        self.gameViewController = nil;
}

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

- (void)dealloc {
    [homeViewController release];
    [gameViewController release];   
    [super dealloc];
}

@end

And here is the home view files which load correctly:

#import <UIKit/UIKit.h>

@class RootViewController;

@interface HomeViewController : UIViewController {  
//GameViewController *gameViewController;
    RootViewController *rootViewController;
}

//@property (retain, nonatomic) GameViewController *gameViewController;
@property (nonatomic, assign) RootViewController *rootViewController;

- (IBAction)showGame:(id)sender;

@end

Implementation file:

#import "HomeViewController.h"
#import "RootViewController.h"

@implementation HomeViewController;

@synthesize rootViewCon开发者_如何转开发troller;

// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad {   
[super viewDidLoad];
}
- (IBAction)showGame:(id)sender{
    GameViewController *gameController = [[GameViewController alloc] initWithNibName:@"GameView" bundle:nil];
    self.rootViewController = gameController;
    [self.rootViewController.view insertSubview:gameController.view atIndex:1];
    [gameController release];   
}

- (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.
}

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

- (void)dealloc {
    [super dealloc];
}

@end


I'm confused by your comment. Here is the additional code snippet:

- (IBAction)showGame:(id)sender { 
    GameViewController *gameController = [[GameViewController alloc] initWithNibName:@"GameView" bundle:nil]; 
    self.rootViewController = gameController; 
    [self.rootViewController.view insertSubview:gameController.view atIndex:1];         
    [gameController release]; 
}

So you're setting the rootViewController of the HomeViewController to equal gameController. Then you're inserting the gameController view into the rootViewController's view. But, the gameController is the rootViewController. I think you have a logic error here.


This is luckily an easy fix - you forgot to include the GameViewController header file. Hence it has no idea what the view property of your GameViewController instance is.


I think this is your problem:

- (void)viewDidLoad {

homeViewController.rootViewController = self;

HomeViewController *homeController = [[HomeViewController alloc]  initWithNibName:@"HomeView" bundle:nil];
self.homeViewController = homeController; 

You assign the rootViewController to homeViewController before you initialize homeViewController. At that point `self.homeViewController' is just empty memory.

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