Category Archives: Core Data

From the README on github:

momdec is a command-line tool for Mac OS X that takes a compiled Core Data model and decompiles it to produce an equivalent xcdatamodel or xcdatamodeld suitable for use in Xcode. The resulting model file can also be used with mogenerator to produce source code files for Core Data entities which have custom subclasses.

My latest open source project. A compiled managed object model contains enough information to reconstruct an equivalent editable model file. So, I thought, wouldn't it be interesting to actually do that?

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Today I'm continuing my series of iCloud/Core Data-related posts with a discussion of duplicate data, how and why it occurs, and what you can do about it in your apps. As with my previous post in this series, today I'm sticking to how things are supposed to work and sometimes actually do. The problem of duplicate data isn't actually specific to iCloud. It can happen in any case where people might create data on different devices and where your app wants to sync that data between the devices. Some sync solutions may try to solve the problem for you, but iCloud does not. Why are Duplicates Possible? In short: Core Data doesn't care if you create multiple objects with identical data fields. You can, if you like, create any number of instances…

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As promised, I'm going to be doing a number posts on using iCloud with Core Data. I'm not sure how many there will be, I'll keep going as long as it takes. Today I'm starting off with some things that, while not actually bugs, may catch a developer off guard. In this post I'm sticking to how iCloud is designed to work, and not getting into the questions of how and when it doesn't work. Some of this is covered here and there in Apple's docs, but I haven't seen it all spelled out. With luck this will save you some trial and error. What have you done for my data lately? Most of the information from Apple covers how to use iCloud in a new application. What if you want to add iCloud to an existing application that already uses Core Data? First…

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“Don’t you just turn on iCloud syncing, and it all Just Works?”

“Just works” might be the customer experience; but developers must do more to support iCloud (or any new OS technology) than simply flipping a switch. Things can go wrong, and they often do.

Rich gets into a lot more technical detail than most of the other iCloud coverage that's come out recently.

I'm way too familiar with the technical issues described there for comfort.

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As some of you know, I've spent a lot of time over the past year working with iCloud in Mac and iOS apps. Specifically, working with Core Data's built-in support for iCloud. I'm going to be doing a series of blog posts covering iCloud in various ways. Today I'm going to start off with an overview covering how iCloud is supposed to work with Core Data and a little about how it actually works in practice. This is an overview, a starting point. Nearly everything here should be read as having an invisible parenthetical "(more on this to come)". My focus Even though iCloud has been out for a while, there still seems to be a fair amount of confusion on the question of what it is. After seeing comments made at The Verge's article about iCloud I…

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