New Twiddle

components.share-box.js

import Ember from 'ember';

export default Ember.Component.extend({
  shareText: '',
  
  word: '',
  wordToObserve: '',
    
  actions: {
    onShareEditorValueChanged(shareEditorValue) {
      this.set('shareText', shareEditorValue);
    },
    onSelectHashtag(text) {
      // Trick to trigger a didReceiveAttrs for the same word
      this.set('word', '');
      this.set('word', text);
    }
  }
});

components.share-editor.js

import Ember from 'ember';

export default Ember.Component.extend({
  value: '',

  sharingEventManager: Ember.inject.service(),
  
  // PROBLEM: performance issues
  // PROBLEM: not triggered when it is the same word
  onWordToObserveChanged: Ember.observer('wordToObserve', function() { 
    console.log('onWordToObserveChanged', this.get('wordToObserve'));
    this.insertText(this.get('wordToObserve'));
  }),
  
  didInsertElement() {
    // PROBLEM: services are singleton, won't play well if
    // there are multiple instances of this component
    this.get('sharingEventManager').on('insertWord', this, function(text) {
      this.insertText(text);
    });
  },
  
  // PROBLEM: not triggered when it is the same word
  //   => set word to empty string before setting the new value (trick to trigger a didReceiveAttrs for the same word)
  // PROBLEM: cannot target which attr to listen to
  //   => can be solved by ember-diff-attrs addon
	didReceiveAttrs() {
    console.log('didReceiveAttrs');
    if (this.get('word')) {
      this.insertText(this.get('word'));
    }
  },
  
  insertText(text) {
    this.set('value', `${this.get('value')}${text}`);
    this.get('onValueChange')(this.get('value'));
  },
  
  actions: {
    onValueChange() {
      this.get('onValueChange')(this.get('value'));
    },
  }
});

components.share-suggestions-attrs.js

import Ember from 'ember';

export default Ember.Component.extend({
  actions: {
    onSelectText(text) {
      this.get('onSelectText')(text);
    }
  }
});

components.share-suggestions-evented.js

import Ember from 'ember';

export default Ember.Component.extend({
  sharingEventManager: Ember.inject.service(),
  
  actions: {
    onSelectText(text) {
      this.get('sharingEventManager').trigger('insertWord', text);
    }
  }
});

components.share-suggestions-observer.js

import Ember from 'ember';

export default Ember.Component.extend({
  actions: {
    onSelectText(text) {
      this.set('wordToObserve', text);
    }
  }
});

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle'
});

services.sharing-event-manager.js

import Ember from 'ember';

export default Ember.Service.extend(Ember.Evented, {
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{share-box}}
<br>
<br>

templates.components.share-box.hbs

{{share-editor word=word wordToObserve=wordToObserve onValueChange=(action "onShareEditorValueChanged")}}

{{share-suggestions-attrs onSelectText=(action "onSelectHashtag")}}

{{share-suggestions-observer wordToObserve=wordToObserve}}

{{share-suggestions-evented}}

<p>Share text is:</p>
{{shareText}}

templates.components.share-editor.hbs

{{textarea input=(action "onValueChange") value=value}}

templates.components.share-suggestions-attrs.hbs

<button onclick={{action "onSelectText" "#hashtag-attr1"}}>#hashtag-attr1</button>

<button onclick={{action "onSelectText" "#hashtag-attr2"}}>#hashtag-attr2</button>

templates.components.share-suggestions-evented.hbs

<button onclick={{action "onSelectText" "#hashtag-evented1"}}>#hashtag-evented1</button>

<button onclick={{action "onSelectText" "#hashtag-evented2"}}>#hashtag-evented2</button>

templates.components.share-suggestions-observer.hbs

<button onclick={{action "onSelectText" "#hashtag-observer1"}}>#hashtag-observer1</button>

<button onclick={{action "onSelectText" "#hashtag-observer2"}}>#hashtag-observer2</button>

twiddle.json

{
  "version": "0.12.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.12.0",
    "ember-template-compiler": "2.12.0",
    "ember-testing": "2.12.0"
  },
  "addons": {
    "ember-data": "2.12.1"
  }
}