Ember Polaris vs Alpine - JavaScript 框架语法对比

响应式

声明状态

Ember Polaris

import Component from "@glimmer/component";

export default class NameComponent extends Component {
  name = "张三";

  <template>
    <h1>你好 {{this.name}}</h1>
  </template>
}

Alpine

<h1 x-data="{ name: '张三' }" x-text="name"></h1>

更新状态

Ember Polaris

import Component from "@glimmer/component";
import { tracked } from "@glimmer/tracking";

export default class CounterComponent extends Component {
  @tracked name = "张三";

  constructor(owner, args) {
    super(owner, args);

    this.name = "李四";
  }

  <template>
    <h1>你好 {{this.name}}</h1>
  </template>
}

Alpine

<h1 x-data="{ name: '张三' }" x-init="name = '李四'" x-text="name"></h1>

计算属性

Ember Polaris

import Component, { tracked } from "@glimmer/component";

export default class DoubleCount extends Component {
  @tracked count = 10;

  get doubleCount() {
    return this.count * 2;
  }

  <template>
    <div>{{this.doubleCount}}</div>
  </template>
}

Alpine

<h1
  x-data="{
  count : 10,
  get doubleCount() { return this.count * 2 }
}"
  x-text="doubleCount"
></h1>

模板语法

最简模板

Ember Polaris

<template>
  <h1>你好，世界</h1>
</template>

Alpine

<h1>你好，世界</h1>

样式

Ember Polaris

<template>
  <h1 class="title">我是红色的</h1>
  <button style="font-size: 10rem;">我是一个按钮</button>

  <style>
    .title {
      color: red;
    }
  </style>
</template>

Alpine

<h1 class="title">我是红色的</h1>
<button style="font-size: 10rem">我是一个按钮</button>

<style>
  .title {
    color: red;
  }
</style>

DOM循环

Ember Polaris

const colors = ["红", "绿", "蓝"];

<template>
  <ul>
    {{#each colors as |color|}}
      <li>{{color}}</li>
    {{/each}}
  </ul>
</template>

Alpine

<ul x-data="{ colors: ['红', '绿', '蓝'] }">
  <template x-for="color in colors">
    <li x-text="color"></li>
  </template>
</ul>

点击事件

Ember Polaris

import Component from "@glimmer/component";
import { tracked } from "@glimmer/tracking";

export default class Counter extends Component {
  @tracked count = 0;

  incrementCount = () => this.count++;

  <template>
    <p>计数器: {{this.count}}</p>
    <button {{on "click" this.incrementCount}}>+1</button>
  </template>
}

Alpine

<div x-data="{ count: 0 }">
  <p>计数器: <span x-text="count"></span></p>
  <button x-on:click="count++">+1</button>
</div>

DOM引用

Ember Polaris

import { modifier } from "ember-modifier";

const autofocus = modifier((element) => element.focus());

<template>
  <input {{autofocus}} />
</template>

Alpine

<input x-init="$el.focus();" />

条件渲染

Ember Polaris

import Component from "@glimmer/component";
import { tracked } from "@glimmer/tracking";

const TRAFFIC_LIGHTS = ["红灯", "黄灯", "绿灯"];

export default class TrafficLight extends Component {
  @tracked lightIndex = 0;

  get light() {
    return TRAFFIC_LIGHTS[this.lightIndex];
  }

  nextLight = () => {
    this.lightIndex = (this.lightIndex + 1) % TRAFFIC_LIGHTS.length;
  };

  <template>
    <button {{on "click" this.nextLight}}>下一个灯</button>
    <p>现在亮着的是: {{this.light}}</p>
    <p>
      你应该
      {{#if (eq this.light "红灯")}}
        停下
      {{else if (eq this.light "黄灯")}}
        慢行
      {{else if (eq this.light "绿灯")}}
        赶紧走
      {{/if}}
    </p>
  </template>
}

Alpine

<div
  x-data="{
  TRAFFIC_LIGHTS: ['红灯', '黄灯', '绿灯'],
  lightIndex: 0,
  get light() { return this.TRAFFIC_LIGHTS[this.lightIndex] },
  nextLight() {
    this.lightIndex = (this.lightIndex + 1) % this.TRAFFIC_LIGHTS.length;
  }
}"
>
  <button x-on:click="nextLight">下一个灯</button>
  <p>现在亮着的是: <span x-text="light"></span></p>
  <p>
    你应该
    <span x-show="light === '红灯'">停下</span>
    <span x-show="light === '黄灯'">慢行</span>
    <span x-show="light === '绿灯'">赶紧走</span>
  </p>
</div>

生命周期

组件加载时

Ember Polaris

const pageTitle = () => document.title;

<template>
  <p>页面标题: {{(pageTitle)}}</p>
</template>

Alpine

<p
  x-data="{ pageTitle: '' }"
  x-init="$nextTick(() => { pageTitle = document.title })"
>
  页面标题: <span x-text="pageTitle"></span>
</p>

组件卸载时

Ember Polaris

import Component from "@glimmer/component";
import { tracked } from "@glimmer/tracking";
import { registerDestructor } from "@ember/destroyable";

export default class Time extends Component {
  @tracked time = new Date().toLocaleTimeString();

  constructor(owner, args) {
    super(owner, args);

    let timer = setInterval(() => {
      this.time = new Date().toLocaleTimeString();
    }, 1000);

    registerDestructor(this, () => clearInterval(timer));
  }

  <template>
    <p>当前时间: {{this.time}}</p>
  </template>
}

Alpine

<p
  x-data="{
  time: new Date().toLocaleTimeString(),
  timer: null,
  init() { this.timer = setInterval(() => (this.time = new Date().toLocaleTimeString()), 1000) },
  destroy() { clearInterval(this.timer) }
}"
>
  当前时间: <span x-text="time"></span>
</p>

组件组合

组件Props传参

Ember Polaris

import UserProfile from "./user-profile.gjs";

const favoriteColors = ["green", "blue", "red"];

<template>
  <UserProfile
    @name="张三"
    @age={{20}}
    @favouriteColors={{favoriteColors}}
    @isAvailable={{true}}
  />
</template>

Alpine

<!--Alpine JS suggests using a server-side templating engine or another frontend framework in conjunction with Alpine to do this-->

<div
  x-data="{
  name: '张三',
  age: 20,
  favouriteColors: ['green', 'blue', 'red'],
  isAvailable: true
}"
>
  <p>我的名字是 <span x-text="张三"></span></p>
  <p>My age is <span x-text="age"></span></p>
  <p>
    My favourite colors are <span x-text="favouriteColors.join(', ')"></span>
  </p>
  <p>I am <span x-text="isAvailable ? 'available' : 'not available'"></span></p>
</div>

向父组件emit事件

Ember Polaris

<template>
  <button {{on "click" @onYes}}> 是的！ </button>
  <button {{on "click" @onNo}}> 不是！ </button>
</template>

Alpine

<div
  x-data="{ isHappy: true }"
  x-on:yes="isHappy = true"
  x-on:no="isHappy = false"
>
  <p>你快乐吗?</p>
  <div>
    <button x-on:click="$dispatch('yes')">是的！</button>
    <button x-on:click="$dispatch('no')">不是！</button>
  </div>
  <p style="font-size: 50px" x-text="isHappy ? '😀' : '😥'"></p>
</div>

slot插槽

Ember Polaris

import FunnyButton from "./funny-button";

<template>
  <FunnyButton>点我!</FunnyButton>
</template>

Alpine

<!--Alpine JS suggests using a server-side templating engine or another frontend framework in conjunction with Alpine to do this-->

<button
  x-data
  x-text="'点我!'"
  style="
    background: rgba(0, 0, 0, 0.4);
    color: #fff;
    padding: 10px 20px;
    font-size: 30px;
    border: 2px solid #fff;
    margin: 8px;
    transform: scale(0.9);
    box-shadow: 4px 4px rgba(0, 0, 0, 0.4);
    transition: transform 0.2s cubic-bezier(0.34, 1.65, 0.88, 0.925) 0s;
    outline: 0;
  "
>
  <span>默认slot内容</span>
</button>

slot插槽内容

Ember Polaris

import FunnyButton from "./funny-button";

<template>
  <FunnyButton />
  <FunnyButton>这是传到slot的内容!</FunnyButton>
</template>

Alpine

<!--Alpine JS suggests using a server-side templating engine or another frontend framework in conjunction with Alpine to do this-->

<button
  x-data
  style="
    background: rgba(0, 0, 0, 0.4);
    color: #fff;
    padding: 10px 20px;
    font-size: 30px;
    border: 2px solid #fff;
    margin: 8px;
    transform: scale(0.9);
    box-shadow: 4px 4px rgba(0, 0, 0, 0.4);
    transition: transform 0.2s cubic-bezier(0.34, 1.65, 0.88, 0.925) 0s;
    outline: 0;
  "
>
  <span>默认slot内容</span>
</button>

<button
  x-data
  x-text="'这是传到slot的内容!'"
  style="
    background: rgba(0, 0, 0, 0.4);
    color: #fff;
    padding: 10px 20px;
    font-size: 30px;
    border: 2px solid #fff;
    margin: 8px;
    transform: scale(0.9);
    box-shadow: 4px 4px rgba(0, 0, 0, 0.4);
    transition: transform 0.2s cubic-bezier(0.34, 1.65, 0.88, 0.925) 0s;
    outline: 0;
  "
>
  <span>默认slot内容</span>
</button>

上下文

Ember Polaris

import UserProfile from "./user-profile";

<template>
    <UserProfile />
</template>

Alpine

<!-- x-text 必须用在带有 x-data 的元素或其子元素上。 -->
<!-- 这两个元素可以共用一个带有 x-data 的父元素，也可以像下面这样分别添加 x-data： -->

<h1 x-data>
  欢迎回来, <span x-text="$store.user.username">未知用户</span>
</h1>

<div x-data>
  <h2>我的简介</h2>
  <p>用户名: <span x-text="$store.user.username"></span></p>
  <p>邮箱: <span x-text="$store.user.email"></span></p>
  <button @click="$store.user.updateUsername('李四')">
    更新用户名为 李四
  </button>
</div>

<script>
  document.addEventListener("alpine:init", () => {
    Alpine.store("user", {
      id: 1,
      username: "abcdefg",
      email: "[email protected]",

      updateUsername(newUsername) {
        this.username = newUsername;
      },
    });
  });
</script>

表单输入

输入框

Ember Polaris

import Component from "@glimmer/component";
import { tracked } from "@glimmer/tracking";

export default class InputHello extends Component {
  @tracked text = "你好世界";

  handleInput = (event) => (this.text = event.target.value);

  <template>
    <p>{{this.text}}</p>
    <input value={{this.text}} {{on "input" this.handleInput}} />
  </template>
}

Alpine

<div x-data="{ text: '你好世界' }">
  <p x-text="text"></p>
  <input x-model="text" />
</div>

复选框

Ember Polaris

import Component from "@glimmer/component";
import { tracked } from "@glimmer/tracking";

export default class InputHello extends Component {
  @tracked isAvailable = false;

  handleChange = (event) => (this.isAvailable = event.target.checked);

  <template>
    <input
      id="is-available"
      type="checkbox"
      checked={{this.isAvailable}}
      {{on "change" this.handleChange}}
    />
    <label for="is-available">这是一个checkbox</label>
  </template>
}

Alpine

<div x-data="{ isAvailable: true }">
  <input id="is-available" x-model="isAvailable" type="checkbox" />
  <label for="is-available">这是一个checkbox</label>
</div>

单选框

Ember Polaris

import Component from "@glimmer/component";
import { tracked } from "@glimmer/tracking";

export default class PickPill extends Component {
  @tracked picked = "red";

  handleChange = (event) => (this.picked = event.target.value);

  <template>
    <div>你选择了: {{this.picked}}</div>

    <input
      id="blue-pill"
      type="radio"
      value="blue"
      checked={{eq this.picked "blue"}}
      {{on "change" this.handleChange}}
    />
    <label htmlFor="blue-pill">蓝色</label>

    <input
      id="red-pill"
      type="radio"
      value="red"
      checked={{eq this.picked "red"}}
      {{on "change" this.handleChange}}
    />
    <label htmlFor="red-pill">红色</label>
  </template>
}

Alpine

<div x-data="{ picked: 'red' }">
  <div>你选择了: <span x-text="picked"></span></div>

  <input id="blue-pill" x-model="picked" type="radio" value="blue" />
  <label for="blue-pill">蓝色</label>

  <input id="red-pill" x-model="picked" type="radio" value="red" />
  <label for="red-pill">红色</label>
</div>

选择器

Ember Polaris

import Component from "@glimmer/component";
import { tracked } from "@glimmer/tracking";

export default class ColorSelect extends Component {
  @tracked selectedColorId = 2;

  select = (event) => (this.selectedColorId = event.target.value);

  isSelected = (colorId) => this.selectedColorId === colorId;

  colors = [
    { id: 1, text: "红" },
    { id: 2, text: "蓝" },
    { id: 3, text: "绿" },
    { id: 4, text: "灰", isDisabled: true },
  ];

  <template>
    <select {{on "change" this.select}}>
      {{#each this.colors as |color|}}
        <option
          value={{color.id}}
          disabled={{color.isDisabled}}
          selected={{this.isSelected color.id}}
        >
          {{color.text}}
        </option>
      {{/each}}
    </select>
  </template>
}

Alpine

<div
  x-data="{
  selectedColorId: 2,
  colors: [
    { id: 1, text: '红' },
    { id: 2, text: '蓝' },
    { id: 3, text: '绿' },
    { id: 4, text: '灰', isDisabled: true }
  ]
}"
>
  <select x-model.number="selectedColorId">
    <template x-for="color in colors" x-bind:key="color.id">
      <option
        x-text="color.text"
        x-bind:value="color.id"
        x-bind:disabled="!!color.isDisabled"
        x-bind:selected="color.id === selectedColorId"
      ></option>
    </template>
  </select>
</div>

Web应用特性

渲染应用

Ember Polaris

<!doctype html>
<html>
  <body>
    <script type="module" src="./index.js"></script>
  </body>
</html>

Alpine

<h1>你好，世界</h1>

fetch获取数据

Ember Polaris

import Component from "@glimmer/component";
import { tracked } from "@glimmer/tracking";

class State {
  @tracked isLoading = false;
  @tracked error = null;
  @tracked data = null;
}

function fetchUsers() {
  let state = new State();
  
  async function fetchData() {
    try {
      let response = await fetch("https://randomuser.me/api/?results=3");
      let { results: users } = await response.json();
      state.data = users;
      state.error = null;
    } catch (err) {
      state.data = null;
      state.error = err;
    }
    state.isLoading = false;
  }
  
  fetchData();
  return state;
}

export default class App extends Component {
  <template>
    {{#let (this.fetchUsers) as |request|}}
      {{#if request.isLoading}}
        <p>正在获取用户信息……</p>
      {{else if request.error}}
        <p>获取用户信息出错</p>
      {{else}}
        <ul>
          {{#each request.data as |user|}}
            <li>
              <img src={{user.picture.thumbnail}} alt="user" />
              <p>{{user.name.first}} {{user.name.last}}</p>
            </li>
          {{/each}}
        </ul>
      {{/if}}
    {{/let}}
  </template>
}

Alpine

<div
  x-data="
		function fetchUsers() {
			return {
				users: null,
				isLoading: false,
				error: null,
				async init() {
					this.isLoading = true;
					try {
						this.users = (await (await fetch('https://randomuser.me/api/?results=3')).json()).results;
					} catch (err) {
						this.users = [];
						this.error = err
					}
					this.isLoading = false;
				},
			};
		}
	"
>
  <template x-if="isLoading">
    <p>正在获取用户信息……</p>
  </template>

  <template x-if="error">
    <p>获取用户信息出错</p>
  </template>
  <template x-if="!error">
    <ul>
      <template x-for="user in users">
        <li>
          <img
            :src="user.picture.thumbnail"
            :alt="`picture of ${user.name.first} ${user.name.last}`"
          />
          <p x-text="`${user.name.first} ${user.name.last}`"></p>
        </li>
      </template>
    </ul>
  </template>
</div>

响应式 #

声明状态 #

Ember Polaris

Alpine

更新状态 #

Ember Polaris

Alpine

计算属性 #

Ember Polaris

Alpine

模板语法 #

最简模板 #

Ember Polaris

Alpine

样式 #

Ember Polaris

Alpine

DOM循环 #

Ember Polaris

Alpine

点击事件 #

Ember Polaris

Alpine

DOM引用 #

Ember Polaris

Alpine

条件渲染 #

Ember Polaris

Alpine

生命周期 #

组件加载时 #

Ember Polaris

Alpine

组件卸载时 #

Ember Polaris

Alpine

组件组合 #

组件Props传参 #

Ember Polaris

Alpine

向父组件emit事件 #

Ember Polaris

Alpine

slot插槽 #

Ember Polaris

Alpine

slot插槽内容 #

Ember Polaris

Alpine

上下文 #

Ember Polaris

Alpine

表单输入 #

输入框 #

Ember Polaris

Alpine

复选框 #

Ember Polaris

Alpine

单选框 #

Ember Polaris

Alpine

选择器 #

Ember Polaris

Alpine

Web应用特性 #

渲染应用 #

Ember Polaris

Alpine

fetch获取数据 #

Ember Polaris

Alpine

响应式

声明状态

更新状态

计算属性

模板语法

最简模板

样式

DOM循环

点击事件

DOM引用

条件渲染

生命周期

组件加载时

组件卸载时

组件组合

组件Props传参

向父组件emit事件

slot插槽

slot插槽内容

上下文

表单输入

输入框

复选框

单选框

选择器

Web应用特性

渲染应用

fetch获取数据