multiple CollectionObservables to the same Backbone Collection

[bringking]

Can multiple CollectionObservables be bound to the same Backbone collection? In my case I have a singleton collection that contains the data, and I want to bind to it with different instances of kb.collectionObservable. Is this possible?

[bringking]

Seems I traced it down to this line in the debug library line 1522-

!collection || (collection instanceof kb.Collection) || _throwUnexpected(this, 'not a collection');

So what I am seeing is that even if I have a backbone collection like this

var Collection= Backbone.Collection.extend({
    model: ModelObj,
    url: '/ist/rest/ModelObjs'
});

Even if I clone this collection or create a new Collection(), knockback will not bind to the new instantiation? Maybe knockback is modifying the prototype so that every new or cloned instantiation returns true for instanceof?

[agroskin]

You can definitely have multiple collectionObservable, with different filters and sort options:

var panels = new Backbone.Collection([ { dock: 'left', order: 0 }, { dock: 'right', order: 1 }, ..... ]);

var panelsLeft = kb.collectionObservable(panels, {
filters: function (panel) { return panel.get("dock") != "left"; },
sort_attribute: "order"
});

var panelsRight = kb.collectionObservable(panels, {
filters: function (panel) { return panel.get("dock") != "right"; },
sort_attribute: "order"
});

var panelsExpandedLeft = kb.collectionObservable(panels, {
filters: function (panel) { return !panel.get("expanded") || panel.get("dock") != "left";
}});

var panelsExpandedRight = kb.collectionObservable(panels, {
filters: function (panel) { return !panel.get("expanded") || panel.get("dock") != "right";
}});

If you want to SHARE viewmodels, you have to use shareOptions:

http://kmalakoff.github.io/knockback/doc/classes/kb/CollectionObservable.html#shareOptions-instance