Why would you use Interface Builder for iPhone Development?

15 Jul 2009 Why would you use Interface Builder for iPhone Development?

I don’t understand why you’d use Interface Builder to create a UI for an iPhone application.

When I started building my first iPhone application at Shine, my colleagues advised me to avoid using Interface Builder. They’d tried using it when they were first starting out, but found that it just got in the way and made the learning curve steeper than it needed to be.

The problem for me was that many of the available books and tutorials for iPhone development used Interface Builder. Many of the sample apps on Apple’s site use it as well. I was having trouble figuring out how to not use it, so I took a deep breath and gave it a go.

I got confused pretty quickly. After thrashing around for a day or so, a colleague took pity on me and showed me how to bootstrap an iPhone user interface in code. I ditched Interface Builder and never looked back.

Sure, I probably would have figured it out, but why make life harder than it needs to be? As a new iPhone developer, I was already trying to get my head around Objective-C, Cocoa and XCode. Why add Interface Builder and NIB files to the list, for very little apparent benefit?

My Theory

Perhaps all the iPhone books and tutorials have been written by people who already had experience developing with Interface Builder and Nibs for Mac OS X.

Don’t get me wrong – I don’t have a problem with Interface Builder. It’s just that I wonder whether Interface Builder is more suited to it’s original purpose: building complex user interfaces that are to be used on a desktop computer.

iPhone applications, on the other hand, have a very limited set of widgets and layouts to choose from. Furthermore, there’s a limited amount of stuff you should put on a single screen.

Consequently it seems like overkill to crack out Interface Builder for an iPhone application.

More controversially, in my experience with GUI builders I’ve found that as soon as you try and build anything non-trivial, you’re going to have to code it by hand anyway. Furthermore, if an interface is so simple that you could build it with a GUI builder, I’ve found that it’s probably quicker to code it yourself. I’m not sure that Interface Builder is any exception to this observation.

To support these assertions, I’d like to point out that one of the more complex (and useful) sample iPhone applications that Apple provide – ‘TheElements‘ (which navigates the periodic table) – doesn’t use NIB files.

How to do it

So how does one bootstrap an iPhone interface without a NIB file? It turns out that it’s very easy to do, but there aren’t many examples out there on how to do it. So for the sake of knowledge-dissemination, here’s how you write a main.c that does it:

#import <UIKit/UIKit.h>

int main(int argc, char *argv[]) {
    NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
    int retVal = UIApplicationMain(argc, argv, nil, @"MyAppDelegate");
    [pool release];
    return retVal;
}

The key part is that you provide the name of the AppDelegate you want to use to the UIApplicationMain method, instead of leaving it as nil.

You’d then just code your AppDelegate to bootstrap the UI however you see fit:

#import "MyAppDelegate.h"

@implementation MyAppDelegate

- (void)applicationDidFinishLaunching:(UIApplication *)application {
	UIWindow *window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
	...
              Setup your controllers and views in here.
        ...
	[window addSubview:myViews];
	[window makeKeyAndVisible];
}

Finally, remove the property with the key ‘Main nib file base name’ (the raw key name is ‘NSMainNibFile’) from your Info.plist file.

What do you think?

Of course, as a newby to iPhone development, perhaps I’m missing something here.
If you’re new to iPhone development, have you found Interface Builder useful? If so, I’d like to hear about it. I can only speak from my own experiences (and those of my colleagues), so would be interested in hearing about the experiences of others.