{{service-action}} helper

application.controller.js

import Ember from 'ember';

const { Controller } = Ember;

export default class ApplicationController extends Controller {
  constructor() {
    super();
    this.application_name = '<code>service-action</code> helper';
  }
}

application.route.js

import Ember from 'ember';

const { Route } = Ember;

export default class ApplicationRoute extends Route {
  activate() {
    super.activate(...arguments);
    document.body.classList.add('standard');
  }
}

application.template.hbs

<header class="container-fluid">
  <h1>Demo: {{{application_name}}}</h1>
</header>

<p class="container-fluid">
	<blockquote>
  	这个 Demo 演示了各种调用来自 <code>service</code> 的方法的姿势，并提供了一个自制的 <code>service-action</code> 作为终极解决方案：
  </blockquote>
  <blockquote>
    <code>\{{service-action}}</code> 是一个 helper，可以帮助你直接调用来自任意 <code>service</code> 的方法，或是 <code>service.actions</code> 里面的方法。它的优点主要是：1. 彻底解决了 <code>this</code> 在方法内部的指向混乱问题，将永远指向 <code>service</code> 对象自身，并且不需要在调用时指明；2. 始终保持参数传递的顺序和一般的 <code>\{{action}}</code> helper 的行为一致，所以不会出现诸如 <code>event</code> 参数的位置变来变去的问题。
  </blockquote>
  <blockquote>
    它的用法很简单：
  </blockquote>
  <blockquote>
  	<code>onclick=\{{service-action "service_name" "action_name" ...args}}</code>
  </blockquote>
</p>

<hr>

<main class="container-fluid">
	{{outlet}}
</main>

helpers.service-action.js

import Ember from 'ember';

const { Helper, getOwner } = Ember;

export default class ServiceActionHelper extends Helper {
  compute([serviceName, actionName, ...args]) {
    const service = getOwner(this).lookup(`service:${serviceName}`);
    
    return event => {
      return typeof service[actionName] === 'function'
    		? service[actionName].apply(service, [...args, event])
    		: service['actions'][actionName].apply(service, [...args, event]);
    }
  }
}

index.controller.js

import Ember from 'ember';

const { Controller, inject: { service } } = Ember;

export default class IndexController extends Controller {
  constructor() {
    super();
    this.greeting = service();
    
    this.actions = {
      hello(event, whom) {
        console.log(arguments);
        this.get('greeting').hello(...arguments);
      },
      
      goodbye(event, whom) {
        console.log(arguments);
        this.actions.goodbye(...arguments);
      }
    }
  }
}

index.route.js

import Ember from 'ember';

const { Route } = Ember;

export default class IndexRoute extends Route {
}

index.template.hbs

<h2>Examples:</h2>

<ul>
	<li>
  	<button class="btn btn-ghost" onclick={{action "hello" "nightire"}}>You need to&nbsp;<code>get</code>&nbsp;injected service first</button>
  </li>
  <li>
  	<button class="btn btn-ghost" onclick={{action "goodbye"}}>otherwise will throw an error</button>
  </li>
  <li>
  	<button class="btn btn-ghost" onclick={{action greeting.hello}}>or, you try to call it by passing a method reference, but&nbsp;<code>this</code>&nbsp;will be messed up</button>
  </li>
  <li>
  	<button class="btn btn-ghost" onclick={{action "goodbye" "nightire" target=greeting}}>...unless you specify&nbsp;<code>target</code>&nbsp;explicitly, but you can only use methods in&nbsp;<code>actions</code>&nbsp;hash</button>
  </li>
  <!-- unfortunatelly you can call method on target directly like below:
  <li>
  	<button onclick={{action "hello" "nightire" target=greeting}}>...</button>
  </li>
  -->
  <li>
  	<button class="btn btn-ghost" onclick={{service-action "greeting" "hello"}}>use&nbsp;<code>service-action</code>&nbsp;to call method on service directly</button>
  </li>
  <li>
  	<button class="btn btn-ghost" onclick={{service-action "greeting" "goodbye" "nightire"}}>or call method in&nbsp;<code>actions</code>&nbsp;hash</button>
  </li>
</ul>

services.greeting.js

import Ember from 'ember';

const { Service } = Ember;

export default class GreetingService extends Ember.Service {
  constructor() {
    super();
    this.everyone = 'my friend';
    
    this.actions = {
      goodbye (whom, event) {
        console.log(arguments);
    		alert(`Goodbye, ${whom || this.everyone}!`);
  		}
    };
  }
  
  hello(whom, event) {
    console.log(arguments);
    alert(`Hello, ${whom || this.everyone}!`);
  }
}

styles.reboot.css

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  font-family: sans-serif;
  line-height: 1.15;
  -webkit-text-size-adjust: 100%;
  -ms-text-size-adjust: 100%;
  -ms-overflow-style: scrollbar;
  -webkit-tap-highlight-color: transparent;
}

@-ms-viewport {
  width: device-width;
}

article, aside, dialog, figcaption, figure, footer, header, hgroup, main, nav, section {
  display: block;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol";
  font-size: 1rem;
  font-weight: 400;
  line-height: 1.5;
  color: #212529;
  text-align: left;
  background-color: #fff;
}

[tabindex="-1"]:focus {
  outline: 0 !important;
}

hr {
  box-sizing: content-box;
  height: 0;
  overflow: visible;
}

h1, h2, h3, h4, h5, h6 {
  margin-top: 0;
  margin-bottom: 0.5rem;
}

p {
  margin-top: 0;
  margin-bottom: 1rem;
}

abbr[title],
abbr[data-original-title] {
  text-decoration: underline;
  -webkit-text-decoration: underline dotted;
  text-decoration: underline dotted;
  cursor: help;
  border-bottom: 0;
}

address {
  margin-bottom: 1rem;
  font-style: normal;
  line-height: inherit;
}

ol,
ul,
dl {
  margin-top: 0;
  margin-bottom: 1rem;
}

ol ol,
ul ul,
ol ul,
ul ol {
  margin-bottom: 0;
}

dt {
  font-weight: 700;
}

dd {
  margin-bottom: .5rem;
  margin-left: 0;
}

blockquote {
  margin: 0 0 1rem;
}

dfn {
  font-style: italic;
}

b,
strong {
  font-weight: bolder;
}

small {
  font-size: 80%;
}

sub,
sup {
  position: relative;
  font-size: 75%;
  line-height: 0;
  vertical-align: baseline;
}

sub {
  bottom: -.25em;
}

sup {
  top: -.5em;
}

a {
  color: #007bff;
  text-decoration: none;
  background-color: transparent;
  -webkit-text-decoration-skip: objects;
}

a:hover {
  color: #0056b3;
  text-decoration: underline;
}

a:not([href]):not([tabindex]) {
  color: inherit;
  text-decoration: none;
}

a:not([href]):not([tabindex]):hover, a:not([href]):not([tabindex]):focus {
  color: inherit;
  text-decoration: none;
}

a:not([href]):not([tabindex]):focus {
  outline: 0;
}

pre,
code,
kbd,
samp {
  font-family: monospace, monospace;
  font-size: 1em;
}

pre {
  margin-top: 0;
  margin-bottom: 1rem;
  overflow: auto;
  -ms-overflow-style: scrollbar;
}

figure {
  margin: 0 0 1rem;
}

img {
  vertical-align: middle;
  border-style: none;
}

svg:not(:root) {
  overflow: hidden;
}

table {
  border-collapse: collapse;
}

caption {
  padding-top: 0.75rem;
  padding-bottom: 0.75rem;
  color: #6c757d;
  text-align: left;
  caption-side: bottom;
}

th {
  text-align: inherit;
}

label {
  display: inline-block;
  margin-bottom: .5rem;
}

button {
  border-radius: 0;
}

button:focus {
  outline: 1px dotted;
  outline: 5px auto -webkit-focus-ring-color;
}

input,
button,
select,
optgroup,
textarea {
  margin: 0;
  font-family: inherit;
  font-size: inherit;
  line-height: inherit;
}

button,
input {
  overflow: visible;
}

button,
select {
  text-transform: none;
}

button,
html [type="button"],
[type="reset"],
[type="submit"] {
  -webkit-appearance: button;
}

button::-moz-focus-inner,
[type="button"]::-moz-focus-inner,
[type="reset"]::-moz-focus-inner,
[type="submit"]::-moz-focus-inner {
  padding: 0;
  border-style: none;
}

input[type="radio"],
input[type="checkbox"] {
  box-sizing: border-box;
  padding: 0;
}

input[type="date"],
input[type="time"],
input[type="datetime-local"],
input[type="month"] {
  -webkit-appearance: listbox;
}

textarea {
  overflow: auto;
  resize: vertical;
}

fieldset {
  min-width: 0;
  padding: 0;
  margin: 0;
  border: 0;
}

legend {
  display: block;
  width: 100%;
  max-width: 100%;
  padding: 0;
  margin-bottom: .5rem;
  font-size: 1.5rem;
  line-height: inherit;
  color: inherit;
  white-space: normal;
}

progress {
  vertical-align: baseline;
}

[type="number"]::-webkit-inner-spin-button,
[type="number"]::-webkit-outer-spin-button {
  height: auto;
}

[type="search"] {
  outline-offset: -2px;
  -webkit-appearance: none;
}

[type="search"]::-webkit-search-cancel-button,
[type="search"]::-webkit-search-decoration {
  -webkit-appearance: none;
}

::-webkit-file-upload-button {
  font: inherit;
  -webkit-appearance: button;
}

output {
  display: inline-block;
}

summary {
  display: list-item;
  cursor: pointer;
}

template {
  display: none;
}

[hidden] {
  display: none !important;
}

twiddle.json

{
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  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "hack": "//cdn.staticfile.org/hack/0.7.7/hack.css",
    "standard": "//cdn.staticfile.org/hack/0.7.7/standard.css",
    "jquery": "//cdn.staticfile.org/jquery/3.2.1/jquery.min.js",
    "ember": "2.16.2",
    "ember-template-compiler": "2.16.2",
    "ember-testing": "2.16.2"
  },
  "addons": {
    "ember-truth-helpers": "latest"
  }
}