How can this be refactored?

EmberFilterExample.js

//controller

filtered: Ember.computed('filterFn', function (){
return this.get('filterFn')(this.get('allProducts'))
},

actions:{
  updateFilter: function (newFilterFn){
  this.set('filterFn', newFilterFn)
}

//template
{{filter-component
  updateFilter=(action 'updateFilter')
}}

//Component Js

onUpdateFilter: Ember.observer('propertyA', 'propertyB', 'propertyC', function (){
  var newFilterMethod =  //...construct filtering method based on properties
  this.get('updateFilter')(newFilterMethod)
});

The only idea I have is to put an action="updateFilter" on="change" on every input.