javascript - CompositeView where children can come from multiple collections -

here need in nutshell.

i need show dropdown/combobox children can come many collections. these collections' models have text attribute show in dropdown.

i wondering if possible create dropdown's list many collections.

namely:

collection 1 has: text: a, fungus: 9 text: b, fungus: 7 text: c, fungus: 6  collection 2 has: text: q, numberofbugs: 8 text: r, numberofbugs: 9 text: s, numberofbugs: 7 

the list dropdown ends looking like:

<option>a</option> <option>a</option> <option>a</option> <option>q</option> <option>r</option> <option>s</option> 

so if select a, want able a's model fungus attribute, , if select r want r's model has numberofbugs attribute.

the idea 2 collections common attributes, in backend correspond different models.

is there way in marionette/backbone?

some way create dropdown has multiple data sources / collections?

merging 1 collection not work because sync / fetch operations not work correctly.

if collection work in application, make them single collection start , use subcollections using backbone-filtered-collection custom behaviors , sync / fetch: models added subcollection added general one.

var general = new backbone.collection var fungus = new filteredcollection(general) var bugs = new filteredcollection(general)  fungus.filterby(function(model){   return model.has('fungus') })  bugs.filterby(function(model){   return model.has('numberofbugs') })  general.add([     {text: 'a', fungus: 9},     {text: 'b', fungus: 7},     {text: 'c', fungus: 6},     {text: 'q', numberofbugs: 8},     {text: 'r', numberofbugs: 9},     {text: 's', numberofbugs: 7}   ])    // general.length => 6 // fungus.length => 3 // bugs.length => 3 

hope helps