NSKeyValueCoding support for CBLModel class?

[Brendan Duddridge]

Hi,

I've got an NSTokenField in my app and I'm trying to allow the user to drag and drop tokens. Because of that, I need to archive the represented objects (my CBLModel subclass) and do the things that need to be done to make that work, such as implement `encodeWithCoder` and `initWithCoder`. But since CBLModel doesn't implement NSCoding nor does it extend eventually from NSResponder, I'm having a hard time making this work.

In my previous model I defined my base class like this:

@interface BaseEntity : NSResponder <NSCoding>

And that seemed to allow NSKeyValueCoding to function properly for my drag and drop needs.

I'm wondering if there's an alternative technique I should be using to support drag and drop? This is a Mac OS X app btw.

When I try to implement encodeWithCoder and initWithCoder, I am unable to call super and I also get the following error from CBL:

*** Assertion failure in -[TFField setValue:ofProperty:], /Projects/iPhone/couchbase-lite-ios/Source/API/CBLModel.m:481

Invalid parameter not satisfying: _document

I tried encoding 'document', but it's a read-only property:

self.document = [aDecoder decodeObjectForKey:@"document"];

Perhaps I'm going about this all wrong.

Thanks,

Brendan

[Jens Alfke]

On Aug 5, 2015, at 11:30 AM, Brendan Duddridge <bren...@gmail.com> wrote:

When I try to implement encodeWithCoder and initWithCoder, I am unable to call super and I also get the following error from CBL:

Oh, interesting. Yeah, making models encodable is problematic because they should be unique — there should only be one CBLModel instance corresponding to a specific document. Whereas if you could encode/decode them, you could easily end up with duplicates (encode a model, then decode it — now you have two of it.)

I suggest making the token objects just be stubs — for example, use the document ID (an NSString) as the token. It’s easy to map between that and the model object in either direction.

—Jens

[Brendan Duddridge]

Hi Jens,

I think I'll need to create some sort of "proxy" class to represent the model object. Because I need to intermix text and tokens, so there would be no way to distinguish a token from text if the tokens were just instances of NSString.

Right now I have a TFField class that I was trying to encode and I think I'll just create a TFFieldProxy class and use that to convert between the document ID to real TFField objects.

Thanks,

Brendan