Archive for January, 2012
Debugging with GDB: Print-Object and UIView recursiveDescription
In the post Debugging with GDB: Introduction to Commands, Print and Print-Object I covered the basics of the command line inteface in GDB. In this post I’ll show you a trick to print out the entire view hierarchy for UIView objects. In Objective-C, all objects (derived from NSObject) have a description method, which returns an [...]
Updated: Tracking Down EXC_BAD_ACCESS Errors with NSZombieEnabled in Xcode 4
In a previous post Tracking Down EXC_BAD_ACCESS Errors with NSZombieEnabled I explained how the environment variable NSZombieEnabled can help track down EXC_BAD_ACCESS errors, which are typically caused by attempting to access objects that have already been released. With Xcode 4 the process for setting NSZombieEnabled is different than in earlier versions of Xcode. To configure [...]
Delete All Files in Documents Directory
In a recent project, I was using iTunes File Sharing to store various log files and test data. Although you can quickly delete all the files in the Documents directory using iTunes, I also was looking for a way to clean up the same directory when my device was not connected. The first approach I [...]
iOS Open Source : SVProgressHUD Heads Up Display
Although I’ve covered HUDs previously, Sam Vermette has done a nice job with his design and implementation. I like Sam’s approach, the methods for displaying and dismissing heads-up-displays are class methods – this is a nice touch in that you don’t need to worry about allocating and releasing objects. There is an abundance of interesting [...]
Debugging with GDB: Introduction to Commands, Print and Print-Object
GDB is the debugging system built into Xcode. Xcode handles much of the interaction with GDB to provide support for breakpoints, stepping through/over code, wowever, GBD also provides a command line that you can use to work directly with the debugger. This tutorial walks through the basics of the command line interface along with an [...]
iOS Open Source : Doorway Transition with CoreAnimation
Ken Matsui has written a unique transition for moving between views that I want to share with you – the effect is similar to sliding open two doors, with the following view moving toward the front of the display in a smooth, sliding motion. The images below show the basic idea, however, you owe it [...]
iOS 5 : Customize UINavigationBar and UIBarButtonItem with the Appearance API
In a previous post, UIImage and resizableImageWithCapInsets, I explained how to use the method resizableImageWithCapInsets in a UIImage object to set cap insets, which specify areas of an image that are not to be changed when resizing or scaling an image. That post was a segue to this post, which will use images (and cap [...]
