How to add an UIViewController's view as subview

As of iOS 5, Apple now allows you to make custom containers for the purpose of adding a UIViewController to another UIViewController particularly via methods such as addChildViewController so it is indeed possible to nest UIViewControllers

EDIT: Including in-place summary so as to avoid link breakage

I quote:

iOS provides many standard containers to help you organize your apps. However, sometimes you need to create a custom workflow that doesn’t match that provided by any of the system containers. Perhaps in your vision, your app needs a specific organization of child view controllers with specialized navigation gestures or animation transitions between them. To do that, you implement a custom container - Tell me more...

...and:

When you design a container, you create explicit parent-child relationships between your container, the parent, and other view controllers, its children - Tell me more

Sample (courtesy of Apple docs) Adding another view controller’s view to the container’s view hierarchy

- (void) displayContentController: (UIViewController*) content
{
   [self addChildViewController:content];                 
   content.view.frame = [self frameForContentController]; 
   [self.view addSubview:self.currentClientView];
   [content didMoveToParentViewController:self];          
}

Thanks to this guys I did it http://highoncoding.com/Articles/848_Creating_iPad_Dashboard_Using_UIViewController_Containment.aspx

Add UIView, connect it to header:

@property (weak, nonatomic) IBOutlet UIView *addViewToAddPlot;

In - (void)viewDidLoad do this:

ViewControllerToAdd *nonSystemsController = [[ViewControllerToAdd alloc] initWithNibName:@"ViewControllerToAdd" bundle:nil];
    nonSystemsController.view.frame = self.addViewToAddPlot.bounds;
    [self.addViewToAddPlot addSubview:nonSystemsController.view];
    [self addChildViewController:nonSystemsController];
    [nonSystemsController didMoveToParentViewController:self];

Enjoy

This answer is correct for old versions of iOS, but is now obsolete. You should use Micky Duncan's answer, which covers custom containers.

Don't do this! The intent of the UIViewController is to drive the entire screen. It just isn't appropriate for this, and it doesn't really add anything you need.

All you need is an object that owns your custom view. Just use a subclass of UIView itself, so it can be added to your window hierarchy and the memory management is fully automatic.

Point the subview NIB's owner a custom subclass of UIView. Add a contentView outlet to this custom subclass, and point it at the view within the nib. In the custom subclass do something like this:

- (id)initWithFrame: (CGRect)inFrame;
{
    if ( (self = [super initWithFrame: inFrame]) ) {
        [[NSBundle mainBundle] loadNibNamed: @"NibNameHere"
                                      owner: self
                                    options: nil];
        contentView.size = inFrame.size;
        // do extra loading here
        [self addSubview: contentView];
    }
    return self;
}

- (void)dealloc;
{
    self.contentView = nil;
    // additional release here
    [super dealloc];
}

(I'm assuming here you're using initWithFrame: to construct the subview.)

I feel like all of these answers are slightly incomplete, so here's the proper way to add a viewController's view as a subview of another viewController's view:

    [self addChildViewController:viewControllerToAdd];
    [self.view addSubview:viewControllerToAdd.view];
    [viewControllerToAdd didMoveToParentViewController:self];

If you'd like, you can copy this into your code as a snippet. SO doesn't seem to understand code replacement formatting, but they will show up clean in Xcode:

    [self addChildViewController:<#viewControllerToAdd#>];
    [self.view addSubview:<#viewControllerToAdd#>.view];
    [<#viewControllerToAdd#> didMoveToParentViewController:self];

willMove is called automatically w/ addChild. Thanks @iOSSergey

When your custom container calls the addChildViewController: method, it automatically calls the willMoveToParentViewController: method of the view controller to be added as a child before adding it.

Use:

[self.view addSubview:obj.view];

Change the frame size of viewcontroller.view.frame, and then add to subview. [viewcontrollerparent.view addSubview:viewcontroller.view]

You must set the bounds properties to fit that frame. frame its superview properties, and bounds limit the frame in the view itself coordinate system.

You may use PopupController for the same one the SDK which shows UIViewController as subview You may check PopupController

Here is sample code for the same

popup = PopupController
        .create(self.navigationController!)
        .customize(
            [
                .layout(.center),
                .animation(.fadeIn),
                .backgroundStyle(.blackFilter(alpha: 0.8)),
                .dismissWhenTaps(true),
                .scrollable(true)
            ]
        )
        .didShowHandler { popup in
        }
        .didCloseHandler { popup in
    }
    let container = MTMPlayerAndCardSelectionVC.instance()
    container.closeHandler = {() in
        self.popup.dismiss()
    }

    popup.show(container)