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Mark Goebl · Apr 30, 2005, 05:21 PM

Hi,
just got Tiger and tried XCode 2.0. I'm very interested in Core Data and tried to start with a datamodel.

I can add Entities, but everytime I try to create a Relationship or Attribute XCode shows an error and (often crashes).

I get the following error:

Uncaught Exception:
[<XDPMRelationship 0x5722d10> valueForKey:]: lookup of unknown key: 'fetchRequest'.
This class does not have an instance variable of the name fetchRequest or _fetchRequest, nor a method of the name fetchRequest, _fetchRequest, getFetchRequest, or _getFetchRequest

What's wrong?

Mark

Brass · May 1, 2005, 06:12 PM

Haven't got my hands on Tiger yet, but that's very disappointing. I'm also very keen to start using CoreData ASAP, and was very disappointed in the lack of stability in the developer preview (could not do ANYTHING useful with data modelling at all).

Is sure hope they get a stable update out soon, as I've been planning a couple of things that really require CoreData.

Mark Goebl · May 2, 2005, 02:49 PM

I've just deleted any file which could cause the crash:
- deinstalled XCode with the uninstaller from the tiger dvd
- deinstalled Webobjects trial
- deleted every configfile in /library, ../application support, /caches from XCode and Webobjects in the user and system directories
- deleted some Framework files in my user Library dir

And after a reboot and a clean install NOW EVERYTHING WORKS!!!

Angus_D · May 2, 2005, 03:43 PM

If you read the release notes, WebObjects 5.2.3 is not qualified to work with Xcode Tools 2.0. You shouldn't have installed it.

Thinine · May 2, 2005, 03:46 PM

Core Data has been solid for me. In half an hour I created an application that replicated the functionality of my roommate's senior design project. He'd spent an entire semester on it. I spent 30 minutes and had nearly the same functionality. He had to use C# and Access and I used Core Data.

driven · May 4, 2005, 05:22 PM

Originally Posted by Thinine

Core Data has been solid for me. In half an hour I created an application that replicated the functionality of my roommate's senior design project. He'd spent an entire semester on it. I spent 30 minutes and had nearly the same functionality. He had to use C# and Access and I used Core Data.

Wow ... what was it that you are doing?

(I'm new to Mac development). C# and ADO.NET are very powerful for data work ... I'd love to know the project. I'm impressed to say the least.

Thinine · May 4, 2005, 11:28 PM

His project was to create an interface for the database of our county cemetery. He is able to add, delete, and search for records. Core Data gives you all of this functionality for free. Just option-drag your data model to interface builder and it will build an interface for you. Compile this app and you got a full fledged application that can take in data and saves it as an xml file (which was indexed by Spotlight, so it was searchable from the system). This is essentially all that I did. Make the data model, generate the interface, and I'm done. I wrote no code and I had never used Core Data before. There was some additional functionality (generation of payment invoices and perhaps a few other things) which I didn't implement.

Now whether this is a testament to his project's simplicity (and his groups inefficiency) or Core Data's power, I don't know.

driven · May 5, 2005, 07:42 AM

Thanks for the update.

I certainly couldn't have done it in C# with ADO.NET quite as fast as you did it, but it would'nt have taken me a semester either. Then again I've been coding Microsoft systems since they had their name on OS/2. <GRIN>

I really can't wait to get my sea-legs on XCode. I'm really excited about learning something new. (And I'm quickly becoming the enemy at work ... "Why are you learning to code on OSX?")