Should views be created using NIBs or code in iPhone?

Question

Are there any performance, development drawbacks or advantages when designing views using Interface Builder?

Answer 1

Often you want to use Interface Builder; there are several reasons why you would want to do this over programmatic interfaces:

• it is the more accepted way of creating user interfaces, due to its simplicity and visual advantages that you can't achieve as easily by simply using code.
• it helps your applications to conform to the iPhone Human Interface Guidelines, through the use of the markers etc, which Apple encourage developers to follow, in order to maintain consistency and usability across iPhone applications.

Despite this, the main reason why programmatic interfaces are sometimes more favourable over using Interface Builder is for interface elements that need to be created several times - for example, creating n UIImageViews - based on a variable that cannot be replicated in Interface Builder. Programmatic interfaces allow for this flexibility and are usually more efficient in this case.

Note that NIBs/XIBs do also take up memory, and if all of your interfaces are placed in your main NIB file, it will not only increase memory usage by your application (for resources which may not be needed instantly anyway) but it will increase loading time. That being said, however, the normal workaround to this problem is not to use programmatic interfaces, but to place different groups of interface elements in different NIB files, placing the immediately required interfaces in the main NIB file, which gets loaded when the application starts, and other groups of interface elements in other NIB files which get loaded when required.

In short, the general way to go is to use Interface Builder, except for when you need to create a variable amount of elements that cannot easily be dealt with in Interface Builder.