An interesting question came up on Stackoverflow today so I decided to expound upon it in a short blog post.
A situation that I believe we are going to be seeing more and more often is one where application developers are writing multiple “versions” of their applications to be used on the desktop, their iPhone and now the iPad.
Because of that situation, it is becoming even more important that we write as much portable code as possible. Fortunately, our model can be completely portable between the two platforms.
Everything is moving toward the cloud and unless you’re building calculators, unit converters, or miniature golf score keepers your iPhone app needs to know how to get data from it. In this blog post I intend to demonstrate how to set up a simple server application and how to retrieve data from it and post data to it using Cocoa Touch. I have chosen to use PHP on the server side because of it’s simplicity and ubiquity, and because I’ve know it, somewhat. You should, however, be able to implement something similar using your server side language of choice.
In many cases when you go to access remote data, you do so through a web service API. While services based on such technologies as SOAP or XML-RPC are standards that provide reasonable methods for retrieving and updating data, REST seems to be the methodology gaining the most ground lately. For our purpose in this post I won’t get into great detail of how to implement a REST base web service as, again, REST is not a specific implementation but rather a methodology. (Read up on it elsewhere if you don’t understand what this means). However, I will talk about it briefly so that you can get on the right path for doing your own REST implementation.
I had to post a link to this one as well as Fraser does such a great job explaining why the iPad is so compelling . From Fraser’s post:
The tech industry will be in paroxysms of future shock for some time to come. Many will cling to their January-26th notions of what it takes to get “real work” done; cling to the idea that the computer-based part of it is the “real work.”
It’s not. The Real Work is not formatting the margins, installing the printer driver, uploading the document, finishing the PowerPoint slides, running the software update or reinstalling the OS.
The Real Work is teaching the child, healing the patient, selling the house, logging the road defects, fixing the car at the roadside, capturing the table’s order, designing the house and organizing the party.
Exactly! The iPad is genius and it will revolutionize not just books, magazines, etc., but it will revolutionize computing as we know it. I don’t know about you, but I’ve got the new SDK fired up and ready to start rocking some apps and it is a very exciting new platform!
Upon first glance, the UIButton class doesn’t seem to provide what you might expect in terms of customization. This often causes developers to resort to creating buttons in an image editor and then specifying that in the Background field in Interface Builder. This is a fine solution and will likely give you what you need, but with Core Animation layers there is a simpler way to achieve the look you want without having to create an image. This post will demonstrate how.
Last month I was given the opportunity to write an article for The Pragmatic Programmers great magazine called “PragPub”. I am happy to say that the article I wrote for them was published in this month’s edition. The article, titled “Touching the Core”, is a walk through Apple’s great addition to the Core Data API for the iPhone.
Specifically this article walks through using the NSFetchedResultsController and some best practices in its use. The magazine is available for free on their website, [The Pragmatic Bookshelf](http://pragprog.com/magazines).
For those not aware, when you compile an Objective-C application, whether it be for the desktop or for Cocoa Touch devices, the debugging symbols are stripped out of the binaries. Therefore, unlike other languages such as Java, when a crash occurs, there is virtually no way to determine where the crash occurred. However, when the applications are compiled, a dSYM bundle is generated. This bundle allows us to match up the debugging symbols with the application’s crash log to help determine the cause of the crash.
It’s common practice for any software project with multiple coders to use some version control mechanism. CVS or Subversion used to be popular. These days distributed systems like git and Mercurial are the quickly replacing the old standards. But what about the cases when you’re the only coder?
Now that we’re all using XCode 3.2 on Snow Leopard (you are, right?) and building 64-bit apps you may find that not everything 64-bit works when your app is run on Leopard.
Our Core Animation book should be available by the end of the year. Go ahead and pre-order it now at Amazon if you would like ;-). When we started writing for Addison-Wesley back in September of 2008, I had no idea how long to expect it to take to finish a technical book as this was my first. One thing I discovered though, is that it is when you are about ready to go to production you start to realize all of the things that you probably should have added to the book, but didn’t think of in time. This blog post will cover one such item as a way to make up for not thinking of it in time. I may include this in a second edition if there is one, but consider this one a freebie. (more…)
If your app is fullscreen, like a game, has a presentation mode, or plays long running movie files, you’ll want to disable the display from sleeping. DVD Player and Keynote are perhaps the two most obvious examples of this functionality.
At first glance setting a height dynamically for table view cells seems a little daunting and the first most obvious answers that come to mind are not necessarily correct. In this post I will show you how to set your table view cell heights dynamically based upon the text content without subclassing UITableViewCell. You can subclass it, however, doing so does not make the code much cleaner as setting the height is done in your delegate for the table view itself rather than the cell anyhow. Read on to see what you need to know to make dynamic cell height sizing a breeze.
October 17th and October 18th of this year, the Voices That Matter conference will be occurring in Boston. I will be speaking at this conference on the subject of Core Animation. In addition to myself, there is a very nice list of speakers at this conference including Aaron Hillegass, Daniel Jalkut, Fraser Speirs and many others.
Currently, you can get $200.00 off the the price of the conference if you sign up before the 12th of September.
In addition, if you use the speaker code ‘PHASPKR’, you can receive an additional $150.00 off the price. That is a combined discount of $350.00 if you sign up before September 12th.
It is important to develop a consistent build process for your applications. I have written a couple of bash scripts to help me with this process.
I use git for version control and also the services of github. Now in another post on this site Marcus covered how to put git commit checksums in your Info.plist’s CFBundleVersion. I have opted to use Apple Generic Versioning (or agv for short) instead as it has an easy to read incrementing build number and is super easy to script. It’s also great for use with Sparkle since Sparkle uses the CFBundleVersion to see if the appcast has a newer version.
I’ve seen a good bit of sample code that shows how to implement using a UINavigationController in a view controller that is managed by a UITabBarController, but I haven’t seen much on how to do it with Interface Builder. Turns out that it’s pretty simple and I’m going to show you how.