docsify/docs/vue.md
John Jago c0bf897ea4 docs: improve English wording (Guide)
This change improves a few of the phrases so that they sound more natural.
Small stylistic changes are also included, such as consistent use of "GitHub"
instead of "Github".
2021-07-30 11:51:24 -05:00

8.6 KiB

Vue compatibility

Docsify allows Vue content to be added directly to your markdown pages. This can greatly simplify working with data and adding reactivity to your site.

To get started, add Vue 2.x or 3.x to your index.html file. Choose the production version for your live site or the development version for helpful console warnings and Vue.js devtools support.

Vue 2.x

<!-- Production -->
<script src="//cdn.jsdelivr.net/npm/vue@2/dist/vue.min.js"></script>

<!-- Development -->
<script src="//cdn.jsdelivr.net/npm/vue@2/dist/vue.js"></script>

Vue 3.x

<!-- Production -->
<script src="//cdn.jsdelivr.net/npm/vue@3/dist/vue.global.prod.js"></script>

<!-- Development -->
<script src="//cdn.jsdelivr.net/npm/vue@3/dist/vue.global.js"></script>

Template syntax

Vue template syntax is used to create dynamic content. With no additional configuration, this syntax offers several useful features like support for JavaScript expressions and Vue directives for loops and conditional rendering.

<!-- Hide in docsify, show elsewhere (e.g. GitHub) -->
<p v-if="false">Text for GitHub</p>

<!-- Sequenced content (i.e. loop)-->
<ul>
  <li v-for="i in 3">Item {{ i }}</li>
</ul>

<!-- JavaScript expressions -->
<p>2 + 2 = {{ 2 + 2 }}</p>

Text for GitHub

  • Item {{ i }}

2 + 2 = {{ 2 + 2 }}

View output on GitHub

Vue content becomes more interesting when data, computed properties, methods, and lifecycle hooks are used. These options can be specified as global options or within DOM mounts and components.

Data

{
  data() {
    return {
      message: 'Hello, World!'
    };
  }
}
<!-- Show message in docsify, show "{{ message }}" elsewhere (e.g. GitHub)  -->
{{ message }}

<!-- Show message in docsify, hide elsewhere (e.g. GitHub)  -->
<p v-text="message"></p>

<!-- Show message in docsify, show text elsewhere (e.g. GitHub)  -->
<p v-text="message">Text for GitHub</p>

{{ message }}

Text for GitHub

View output on GitHub

Computed properties

{
  computed: {
    timeOfDay() {
      const date = new Date();
      const hours = date.getHours();

      if (hours < 12) {
        return 'morning';
      }
      else if (hours < 18) {
        return 'afternoon';
      }
      else {
        return 'evening'
      }
    }
  },
}
Good {{ timeOfDay }}!

Good {{ timeOfDay }}!

Methods

{
  data() {
    return {
      message: 'Hello, World!'
    };
  },
  methods: {
    hello() {
      alert(this.message);
    }
  },
}
<button @click="hello">Say Hello</button>

Say Hello

Lifecycle Hooks

{
  data() {
    return {
      images: null,
    };
  },
  created() {
    fetch('https://api.domain.com/')
      .then(response => response.json())
      .then(data => (this.images = data))
      .catch(err => console.log(err));
  }
}

// API response:
// [
//   { title: 'Image 1', url: 'https://domain.com/1.jpg' },
//   { title: 'Image 2', url: 'https://domain.com/2.jpg' },
//   { title: 'Image 3', url: 'https://domain.com/3.jpg' },
// ];
<div style="display: flex;">
  <figure style="flex: 1;">
    <img v-for="image in images" :src="image.url" :title="image.title">
    <figcaption>{{ image.title }}</figcaption>
  </figure>
</div>
{{ image.title }}

Global options

Use vueGlobalOptions to specify Vue options for use with Vue content not explicitly mounted with vueMounts, vueComponents, or a markdown script. Changes to global data will persist and be reflected anywhere global references are used.

window.$docsify = {
  vueGlobalOptions: {
    data() {
      return {
        count: 0,
      };
    },
  },
};
<p>
  <button @click="count -= 1">-</button>
  {{ count }}
  <button @click="count += 1">+</button>
</p>

- {{ count }} +

Notice the behavior when multiple global counters are rendered:

- {{ count }} +

Changes made to one counter affect the both counters. This is because both instances reference the same global count value. Now, navigate to a new page and return to this section to see how changes made to global data persist between page loads.

Mounts

Use vueMounts to specify DOM elements to mount as Vue instances and their associated options. Mount elements are specified using a CSS selector as the key with an object containing Vue options as their value. Docsify will mount the first matching element in the main content area each time a new page is loaded. Mount element data is unique for each instance and will not persist as users navigate the site.

window.$docsify = {
  vueMounts: {
    '#counter': {
      data() {
        return {
          count: 0,
        };
      },
    },
  },
};
<div id="counter">
  <button @click="count -= 1">-</button>
  {{ count }}
  <button @click="count += 1">+</button>
</div>
- {{ count }} +

Components

Use vueComponents to create and register global Vue components. Components are specified using the component name as the key with an object containing Vue options as the value. Component data is unique for each instance and will not persist as users navigate the site.

window.$docsify = {
  vueComponents: {
    'button-counter': {
      template: `
        <button @click="count += 1">
          You clicked me {{ count }} times
        </button>
      `,
      data() {
        return {
          count: 0,
        };
      },
    },
  },
};
<button-counter></button-counter>
<button-counter></button-counter>

Markdown script

Vue content can mounted using a <script> tag in your markdown pages.

!> Only the first <script> tag in a markdown file is executed. If you wish to mount multiple Vue instances using a script tag, all instances must be mounted within the first script tag in your markdown.

<!-- Vue 2.x  -->
<script>
  new Vue({
    el: '#example',
    // Options...
  });
</script>
<!-- Vue 3.x  -->
<script>
  Vue.createApp({
    // Options...
  }).mount('#example');
</script>

Technical Notes

  • Docsify processes Vue content in the following order on each page load:
    1. Execute markdown <script>
    2. Register global vueComponents
    3. Mount vueMounts
    4. Auto-mount unmounted vueComponents
    5. Auto-mount unmounted Vue template syntax using vueGlobalOptions
  • When auto-mounting Vue content, docsify will mount each top-level element in your markdown that contains template syntax or a component. For example, in the following HTML the top-level <p>, <my-component />, and <div> elements will be mounted.
    <p>{{ foo }}</p>
    <my-component />
    <div>
      <span>{{ bar }}</span>
      <some-other-component />
    </div>
    
  • Docsify will not mount an existing Vue instance or an element that contains an existing Vue instance.
  • Docsify will automatically destroy/unmount all Vue instances it creates before each page load.