Question

New to iOS, coming from the Java / Swing world, where I’m used to creating UIs programmatically, letting components size themselves and using various clever layout managers to arrange things.

It already seems clear that the iOS way is to make heavy use of Interface Builder, with a lot of fixed sizing and positioning. I’m not sure IB is ever going to come naturally, but I guess fixed layouts make sense given that you’re working with limited space and a fixed window size.

It still seems like I’m writing a lot of boilerplate, though, and violating DRY, and so on.

Can somebody point me to a good primer on laying out iOS UIs, particularly programmatic UIs?

Answer 1

You don’t really need to use IB to write MonoTouch apps. I almost never do. The CocoaTouch API is fairly simple and straightforward to develop on.

I haven’t really found any writeup on UI development other than the apple documentation (which is really good, by the way, worthy reading), so here goes a couple of tips, based on my experience:

• Inheritance is key to maintaining the code clean. You can inherit from basically any class in the API, like buttons, controllers, views, etc. Inherit and add your customizations in those classes. Don’t shove everything in the AppDelegate like many examples show. You’ll thank me later on.
• Have I mentioned inheritance already?
• The one thing iOS doesn’t have is a layout manager, so if you’re used to Java like you mentioned, this will sound a little strange. Different from what Java people think, this is not a big deal. UITableViews help tremendously with this (vide next point).
• A lot of iphone apps are built on top of the UITableViewController, even apps that don’t look like tables. It’s a great framework to do anything related to scrolling. Learn to use it well. Almost anything that scrolls vertically is a UITVC. Follow the guidelines that define when you create and when you dispose cells and objects.
• Be careful every time you add a Frame location in your control. Instead of setting hardcoded values, try using offsets from other locations (x+40, for example) whenever possible.
• Make sure you add your views to the proper container as necessary. For example, if you’re adding a global “Loading” view, add it to the Window object, while if you’re adding a image on the left side of a table cell, use the ContentView. iOS changes those special views automatically all the time (resizing screen to fit “on call” bar at top, or rotating phone).
• Miguel de Icaza has created a great framework for managing forms and tables, called MonoTouch Dialog. Take a look, and enjoy.