polymer-array-bubble-up-example/app/components/example-component/example-component.html

<link rel="import" href="/polymer/polymer.html">
<link rel="import" href="/components/another-component/another-component.html">

<dom-module id="example-component">
    <template>
        <style>
            :host {
                display: block;
            }
        </style>

        <h1>Example</h1>
        
        <h2>List of elements</h2>
        <template is="dom-repeat" items="{{elements}}" as="item" indexAs="index">
            <another-component element="{{item}}" index={{index}} ident$="{{index}}"></another-component>
        </template>

    </template>
    <script>
        var fred = {"name": "fred"};
        var tom = {"name": "tom"};

        Polymer({
            is: 'example-component',
            properties: {
                elements: {
                    type: Array,
                    value: [{"name": "Main1", "person": fred}, {"name": "Main2", "person": tom}, {"name": "Main3", "person": fred}],
                    notify: true
                }
            }, 

            attached: function(){
                this.addEventListener('change-name', function (e) {
                    console.log("fired");
                    
                    this.elements[e.detail.index].person.name = e.detail.newPersonName;
  
                    for(var i =0; i< this.elements.length; i++){
                        this.notifyPath('elements.'+i+'.person.name'); 
                    }
                    console.log(this.elements);
           
                });
            }

        });
</script>
</dom-module>