Single UIViewcontroller, how to switch among multiple xibs? - ios

Question

I have a subclass of UIViewController:
#interface KBViewController : UIViewController
with multiple xibs, for example, one is a Qwerty and the another is Dvorak layout:
KBViewControllerQuerty~iphone.xib
KBViewControllerDvorak~iphone.xib
So when the user click a button, Qwerty is switch to Dvorak. As you may see, the code logic is identical for both keyboard layouts. What I need is to reload the view with another xib.
Hopefully, all the buttons in the Dvorak xib will be hooks to the responding IBOutlets in KBViewController.
What is the right way to switch between the two xibs?

Answer 1

All Nibs has the designated File's Owner. IBOutlet and IBAction linking is done based upon the File's Owner. So you could define a view controller and two Nibs, with each Nib file's File's Owner set to the defined view controller.
That is, if you set File's Owner of all KBViewController*.xib files to KBViewController and have a KBViewController object somewhere you could load the KBViewController*.xib you want by initWithNibNamed method (recreate the view controller)
If you should maintain the same KBViewController object all along, you could create a KBViewController object without Nib. In KBViewController.m, implement loadView and manually load the UIView object with -[NSBundle loadNibNamed] method (load and change self.view programmatically).
UIView *someView = [[[NSBundle mainBundle] loadNibNamed:#"SomeNibFile"
owner:self
options:nil] objectAtIndex:0];
self.view = someView;
Note owner:self in above code. It must match with File's Owner of the #"SomeNibFile".
To change already loaded view:
id superview = self.view.superview;
[self.view removeFromSuperview];
UIView *someView = [[[NSBundle mainBundle] loadNibNamed:#"SomeNibFile"
owner:self
options:nil] objectAtIndex:0];
self.view = someView;
[superview addSubview:self.view];
More detailed explanation:
Resource Programming Guide - Loading Nib Files Programmatically

Answer 2

You can load your nib file manually and change the view attribute of your view controller or change any view you want, respectively.
UIView *someView = [[[NSBundle mainBundle] loadNibNamed:#"SomeNibFile"
owner:self
options:nil] objectAtIndex:0];
The objectAtIndex:0 is only correct when there is only one UIView root object in your nib file
After loading your view, you can set
self.view = someView;
Of course, if you have a subview in your view controller, then you can change that, too.