Input Caret Position (solution)

components.my-component.js

import Ember from 'ember';

export default Ember.Component.extend({
  
  edited: false,
  
  actions: {
    
    setText(text) {
      this.set('edited', true);
      
      let message = this.get('message');
      message = Ember.copy(message);
      message.text = text;
      
      let indexPath = this.get('indexPath');
      this.attrs.updateMessageAtIndexPath(message, indexPath);
    }
  }
});

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  
  model: null,
  
  components: null,
  
  init() {
    this._super(...arguments);
    
    this.set('model', [
      { text: 'Lorem' },
      { text: 'Ipsum' }
    ]);
    
    this.set('components', []);
    this.updateComponents();
  },
  
  updateComponents() {
    let components = this.get('components');
    this.get('model').forEach((message, index) => {
      let component = components.objectAt(index);
      if (component) {
        component.set('message', message);
      } else {
        components.pushObject({
          message: message
        });
      }
    });
  },
  
  title: Ember.computed('model.@each.text', function() {
  	return this.get('model').mapBy('text').join(' ');
  }),
  
  actions: {
    
    updateMessageAtIndexPath(message, indexPath) {
      let model = this.get('model');
      this.set('model', model.map(function(message, i) {
        if (i === indexPath) {
          return newMessage;
        } else {
          return message;
        }
      }));
      
      this.updateComponents();
    }
  }
});

templates.application.hbs

<h1>{{title}}</h1>

{{#each components as |component index|}}
	{{my-component message=component.message indexPath=index updateMessageAtIndexPath=(action "updateMessageAtIndexPath")}}
{{/each}}

templates.components.my-component.hbs

<input value={{message.text}} oninput={{action "setText" value="target.value"}}>
<span>Edited: {{edited}}</span>

twiddle.json

{
  "version": "0.8.0",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.5.1",
    "ember-data": "2.5.2",
    "ember-template-compiler": "2.5.1"
  }
}