disabledWhen

application.controller.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName:'Ember Twiddle',
  
  alertDisabled: Ember.observer('checked', function() {
    var disabled = Ember.$('#link').hasClass('disabled');
    console.log(`link disabled: ${disabled}`);
  })
});

application.template.hbs

{{input type="checkbox" checked=checked}}
{{link-to 'index' id='link' disabledWhen=checked}}

twiddle.json

{
  "version": "0.4.10",
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/1.13.9/ember.debug.js",
    "ember-data": "https://cdnjs.cloudflare.com/ajax/libs/ember-data.js/1.13.11/ember-data.js",
    "ember-template-compiler": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/1.13.9/ember-template-compiler.js"
  }
}