Are Recursive Collections possible in sproutcore2?

问题

I have a customizable navigation tree that can be nested 3 levels deep.

Templates:

<script type="text/x-handlebars" data-template-name="NavItemView">
    <a {{bindAttr href="href" class="content.className"}}>{{content.name}}</a>
    {{##if content.children}}
        another collection here?
    {{/if}}
</script>
<script type="text/x-handlebars">
    {{collection App.NavItemsCollectionView contentBinding="App.navItemsController" tagName="ul"}}
    {{view App.CreateLinkView id="new-link" placeholder="Name"}}
</script>

data:

nav =[
    {
        "name": "Jethro Larson",
        "children":[
            {
                "name":"Dashboard",
                "href": "index.cfm"
            }
        ]
    },
    {
        "name":"Order Management",
        "children":
        [
            {
                "name":"OM Reports",
                "children":
                [
                    {
                        "name":"Status Updates",
                        "href":"index.cfm?blah"
                    }
                ]
            }
        ]
    }
];

js:

window.App = SC.Application.create();
App.NavItem = SC.Object.extend({
    name: null,
    href: '#',
});
App.navItemsController = SC.ArrayProxy.create({
    content:[],
    addMultiple: function(ar){
        that = this;
        $.each(ar,function(i,item){
            that.pushObject(App.NavItem.create(item));
        });
    }
});
App.NavItemView = SC.View.extend({
    tagName:'li'
    ,templateName: 'NavItemView'
});
App.NavItemsCollectionView = SC.CollectionView.extend({
    itemViewClass: App.NavItemView
});
App.navItemsController.addMultiple(nav);

Is there a way to nest collections so I can link the dom to the data structure?

回答1:

The way you can achieve this is, by putting more logic into your 'NavItemView' template, just include another collection-view at the place you've written "another collection here".

If you've tried that before it might have not worked because of the double hash-char in your if-statement. I've used this already with ten nested levels in a hierarchical progress view. Try

<script type="text/x-handlebars" data-template-name="NavItemView">
   <a {{bindAttr href="href" class="content.className"}}>{{content.name}}</a>
   {{#if content.children}}
     {{view App.NavItemsCollectionView contentBinding="content.children"}}
   {{/if}}
</script>
<script type="text/x-handlebars">
   {{view App.NavItemsCollectionView contentBinding="App.navItemsController" tagName="ul"}}
   {{view App.CreateLinkView id="new-link" placeholder="Name"}}
</script>

as handlebars template.

来源：https://stackoverflow.com/questions/8044919/are-recursive-collections-possible-in-sproutcore2