Queued Background Tasks for Cocoa

The megahertz race is over, and instead we get more execution cores. This means that we as developers must make our applications parallel, in order to take advantage of the new performance. The easiest way to be parallel is to execute tasks in new threads, something that is useful also for lengthy but not resource [...]

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Regular Expressions and Cocoa

Regular expressions is a powerful tool for solving many problems related to text. It can be misused as any good tool, but there are moments when they are the best solution for a given problem. At those moments the lack of regular expressions for Cocoa on Mac OS X and Cocoa Touch on iPhone OS [...]

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Adding Sorted Inserts to Cocoa Arrays

NSArray and NSMutableArray have methods for sorting arrays, NSArray returns new sorted arrays and NSMutableArray can be sorted in place. The sort methods comes in three flavours; using a function, using a selector, or using an array of NSSortDescriptor objects. NSArray admits to sorts being a slow operation, and adds a method pair for comultive [...]

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Bridging the Gap Between Java and Cocoa

Many Java developers are looking at new dynamic languages, such as Groovy and JRuby, mostly because of the freedom and rapid development that a dynamic language allows. Some of my colleagues are also looking at Cocoa and feel daunted at the sight of Objective-C. Here I will use a small example that is easy and [...]

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UIToolbars in iPhone OS 2.x

The new release of iPhone OS 3.0 adds some nice API:s for managing a contextual toolbar. This is well needed as toolbars in the current iteration of iPhone OS is not only poorly documented, it is also quite hard to do right. So I will go over how to do toolbars the right way, for [...]

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iPhone OS and the Lowest Common Denominator

Nishant wrote a good piece on why Apple continue to outdo it’s rivals, he used a variant of a quote by Canadian hockey player Wayne Gretzky to make his point: A good hockey player plays where the puck is. A great hockey player plays where the puck is going to be. This is true as [...]

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Hidden methods in Sony Ericsson Java Platform

It is no secret that the published interfaces for MIDP classes in any JavaME Platform is only a subset of what in reality is there. Most of the native calls needed to interact with the underlying native platform, and other helper methods, are hidden from us. Mostly for good, and sometimes for bad… The Anecdotal [...]

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Proxy Based AOP for Cocoa Touch

UITabBarController is generally used as is, no subclassing required. It creates a UITabBar and manages a list of UIViewControllers, keeping track of the tab in focus, UI creation and everything nice. UITabBarController has a delegate, the UITabBarControllerDelegate protocol. Unfortunately this is not a superset of the UITabBarDelegate protocol, and UITabBarController already implements the UITabBarDelegate protocol [...]

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Finding Subview of a Particular Class in Cocoa

Many of the UIView subclasses in Cocoa, and especially Cocoa Touch are created by combining many different simple views into a more complex view. UITableViewCell is a good example, concisting of almost a dozen subviews, UIImageView for the image, UILabel for the text, etc. It is often nice to be able to reuse existing functionality [...]

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Fixing Image#getRGB()

I have encountered a problem when implementing a nine-patch painter for MIDP 2.0, most of my graphics where left transparent for no-reason. A nine-patch is an image with a flexible center row, and a flexible center column. Most useful when doing themed UI, as a single image can be used to draw buttons, and boxes [...]

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UIButton troubles, a better solution

I described in my previous post how you can change the class of a live object instance. The use-case was a workaround for bug in Cocoa Touch’s UIKit. What if I could fix the bug, instead of applying a work around in my sub-class? Update: Buttons created with UIButtonTypeRoundedRect is a special case returning a [...]

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UIButton troubles, and Obj-C magic

When developing SC68 Player for the iPhone I came upon a quite peculiar problem regarding the UIButton. First the preface I wanted to add a star button to the right side of each row, subclassing UIButton that can manage selected states, images and all I needed, and use it as the accessory view of the [...]

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iPhone Tech Talks – Stockholm

Apple has arranged a world tour of iPhone Tech Talks, and in cold december it was Scandinavia’s turn and a crew of software evangelists from Apple turned up at KTH in Stockholm for a full day of sessions. The sessions are confidential so I will keep this post vague on the technical parts, not revealing [...]

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Accelerometer and Vibration on the iPhone

Last friday I attended an excellent session at Øredev 2008, on Android by Mike Jennings from Google. At the end of the presentation Mike show the code for a simple application with a bouncing blue ball, controlled by the accelerometer. What stroke me was that the git of the application was 85 lines of code, [...]

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HessianKit Released

HessianKit, an implementation of the Hessian binary web service protocol for Objective-C 2.0 have now been released under Apache License 2. It is available on sourceforge at: http://sourceforge.net/projects/hessiankit HessianKit is available for Mac OS X 10.5 and later, and iPhone OS 2.0. The three main goals are: * To be as compliant and forgiving as [...]

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