Another SuperDB Validation Tweak

In ManagedObjectAttributeEditor.m, there is this method:...#pragma mark -#pragma mark Alert View Delegate- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex { if (buttonIndex == [alertView cancelButtonIndex]) { [self.managedObject.managedObjectContext rollback]; [self.navigationController popViewControllerAnimated:YES]; }}@endNow, if you say you're going to fix, and then don't, the context never gets rolled back. It should really be:...#pragma mark -#pragma mark Alert View Delegate- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex { [self.managedObject.managedObjectContext rollback]; if (buttonIndex == [alertView cancelButtonIndex]) { [self.navigationController popViewControllerAnimated:YES];...

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Posted in: Errata,iPhone SDK,More iPhone 3 Development

Well, That's Embarrassing…

In the SuperDB application in More iPhone 3 Development, when we added multi-attribute validation, we inadvertently stopped the single-field validation on birthdate to stop working. In Hero.m, we have this at the end:...- (BOOL)validateForInsert:(NSError **)outError { return [self validateNameOrSecretIdentity:outError];}- (BOOL) validateForUpdate:(NSError **)outError { return [self validateNameOrSecretIdentity:outError];}@endThe method validateNameOrSecretIdentity: does our cross-field validation by looking at the two fields, but it doesn't do the rest of the validations, such as those from the data model, or those from custom validation methods. To handle those, we need a call to super.The easiest way to handle this is to simply call super if validateNameOrSecretIdentity: returns NO....

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Posted in: Book project,Errata,More iPhone 3 Development,SuperDB

iPhone SDK 3.2 GM Seed

The GM release of the iPhone SDK 3.2 is available in iPhone Dev Center (login required). Even though this build is labeled as "GM" and this will probably be the final build before the iPad gets into the hands of consumers, and even though the official policy is that development material is covered by NDA until it goes GM, this build appears to still be under NDA, which means no iPad technical posts yet. Sorry.The release notes and license agreement are pretty clear about the fact that this is still considered pre-release software, so the NDA is still intact and we have to wait a few more days before we can start discussing the nuances of iPad development. I'm assuming that come April 3rd, it will be considered "released". At least, I hope we don't have a repeat of the original iPhone NDA ...

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Posted in: iPad,iPhone SDK

My Last Word on NSFetchedResultsController

Somehow, I never posted my final fix for the various NSFetchedResultsController problems. I submitted a bug report to Apple to get the actual row counts out of NSFetchedResultsController including any deferred inserts and deletes, but went ahead with developing a workaround that keeps track of the inserts and deletes locally. I thought I had posted this information, but I guess I never did (Sorry!). I am optimistic that these issues will be fixed in 3.2, but haven't had time to really run the new version of NSFetchedResultsController through its paces, and even if I had, the NDA would keep me from being able to tell you what I had found. Nevertheless, the fact that it has been updated makes me optimistic that this workaround is temporary and that Apple has finally shipped a production-ready...

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Posted in: Book project,NSFetchedResultsController

Improved Irregular Shape UIButton

I took some of the feedback and improved the UIButton subclass from my last post. I implemented a cache for the alpha data and also incorporates changes based on Alfons Hoogervorst's modifications to my original UIImage category.You can find the new and improved version of the irregular shaped UIButton code he...

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Posted in: iPhone SDK,tutorial

Irregularly Shaped UIButtons

Note: There is an improved version of the code from this blog post right here.You probably know that UIButton allows you to select an image or background image with alpha, and it will respect the alpha. For example, if I create four images that look like this:I can then use create custom buttons in Interface Builder using these images, and whatever is behind the transparent parts of the button will show through (assuming the button is not marked opaque. However, UIButton's hit-testing doesn't take the transparency into account, which means if you overlap these buttons in Interface Builder so they look like this, for example:If you click here:The default hit-testing is going to result in the green diamond button getting pressed, not the blue...

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Posted in: iPhone SDK,tutorial