Comments on: A Moveable Beast

By: Jonathan Saggau

Jonathan Saggau — Thu, 08 Mar 2007 05:35:58 +0000

I have been thinking of core data and order as well lately. My stab at it with a double linked list (minus the NSArrayController… that’s next, I fear) is available on my blog.

http://www.jonathansaggau.com/blog/2007/02/core_data_double_linked_list_h.html
svn co http://jonathansaggau.com/svn/MOLinkedList

By: mathieu

mathieu — Fri, 02 Mar 2007 14:51:01 +0000

Try CocoaTron as well

http://groups.google.com/group/cocotron-dev?hl=en

By: Daniel Jalkut

Daniel Jalkut — Fri, 02 Mar 2007 14:33:16 +0000

KFUPM: Not really - Apple owns Cocoa and makes it available only on Mac computers. But there is an open source project called GNUStep which tries to replicate some of the functionality.

By: KFUPM

KFUPM — Fri, 02 Mar 2007 08:56:03 +0000

is there any version of Cocoa works under windows.!

By: ssanchex

ssanchex — Sat, 24 Feb 2007 15:46:26 +0000

Remembering distribution would NOT be very intuitive.

By: ssanchex

ssanchex — Sat, 24 Feb 2007 15:45:18 +0000

Daniel,

sorry, should have just tested it myself! Yes it seems to work fine the way I would want in FlexTime. I think remembering distribution would be very intuitive. Trying to remember exactly what was wrong with my implementation from six months ago (I’ve removed the code from my head revision) I think I had it working fine but it was going screwy on Undo, I believe because I had (bug ridden) overriddes the add / insert methods of the NSArrayController to also add auto-generation of sequential ID’s and the problems had arisen there as a result of not sitting down and designing it first.

So I think I will make very good use of RSRTVArrayController as it doesn’t exhibit any of the problems I created for myself. Thanks.

Sanjay

By: mathieu

mathieu — Thu, 22 Feb 2007 20:59:18 +0000

I had problems because my app already had a delegate and datasource object, for accepting drops from other table views, and something went bitter and twisted when I tried to merge the two. Ah well.

By: Daniel Jalkut

Daniel Jalkut — Thu, 22 Feb 2007 13:47:55 +0000

Hmm - you know I hadn’t really tested the discontinuous scenario. I just tried it live on FlexTime (download and try it!), which uses the code.

The short answer is: it works as well as I’d guess it would. The discontiguous items all get moved such that they line up, in order, at the point where they are dragged to. They don’t make any effort to interspace themselves in the list at the same frequency as they were selected, if that’s what you’re looking for.

By: ssanchex

ssanchex — Thu, 22 Feb 2007 13:39:25 +0000

Just coming back to this to try and work out which of the three to use. The Adium version doesn’t actually handle ordering itself but simply delegates to another arbitrary object where you have to do the work.

The biggest headache I came across when trying to achieve this was discontiguous selections in the drag operation. I’ve got a feeling that Daniel’s won’t handle it cos it looks awfully similar to the code that I came up with. Daniel, does it work with discontiguous selections?

The BoundNSTableViewDragAndDropDataSource has simpler re-ordering code and is novel because it uses a reverse ordering on the enumeration, which makes me wonder whether it would handle this case? I know I can test it, but anyone know from experience?

By: mathieu

mathieu — Thu, 15 Feb 2007 12:07:44 +0000

3 soultions - yes, now which one to choose! Persisting order in Core Data managedObjects… what’s the best method? Just writing out integers? Or setting relationships? I’ve experimented with the latter, but had all kinds of circular relationship errors and concequent saving errors. I guess I was not being careful enough. So the former works best for me. Is there a better way? (I’m still new)