Vue UI框架的主题切换功能实现

const darkThemeSwitch = () => {
    // id要与前面一致
    const theme_element = document.querySelector('#dark-theme-style');
    if (!theme_element) {
        const new_dark_Theme = document.createElement('link')
        new_dark_Theme.setAttribute('rel', 'stylesheet');
        //刚刚设置的css路径
        new_dark_Theme.setAttribute('href', '/styles/dark.css');
        // id可以自由设置
        new_dark_Theme.setAttribute('id', 'dark-theme-style');
        const docHead = document.querySelector('head');
        docHead?.append(new_dark_Theme);
    } else {
        const parentNode = theme_element?.parentNode;
        parentNode?.removeChild(theme_element);
    }
}

export default darkThemeSwitch;

<template>
    <a-button @click="toggleDark">切换主题</a-button>
</template>

<script setup lang="ts">
    import darkThemeSwitch from '../utils/theme';
    const toggleDark = () => {
        darkThemeSwitch();
    };
</script>

import { useQuasar } from 'quasar'
const $q = useQuasar()

// get status
console.log($q.dark.isActive) // true, false

// get configured status
console.log($q.dark.mode) // "auto", true, false

// set status
$q.dark.set(true) // or false or "auto"

// toggle
$q.dark.toggle()

Plugin.mode = val
if (val === 'auto') {
  if (Plugin.__media === void 0) {
    Plugin.__media = window.matchMedia('(prefers-color-scheme: dark)')
    Plugin.__updateMedia = () => { Plugin.set('auto') }
    Plugin.__media.addListener(Plugin.__updateMedia)
  }

  val = Plugin.__media.matches
}

document.body.classList.remove(`body--${ val === true ? 'light' : 'dark' }`)
document.body.classList.add(`body--${ val === true ? 'dark' : 'light' }`)

import defineReactivePlugin from '../utils/private/define-reactive-plugin.js'
import { isRuntimeSsrPreHydration } from './Platform.js'

const Plugin = defineReactivePlugin({
    // 插件的属性
    isActive: false,
    mode: false
}, {
    __media: void 0,
    // 插件的核心方法
    set(val) {
        if (__QUASAR_SSR_SERVER__) { return }

        Plugin.mode = val
        // 自动主题切换
        if (val === 'auto') {
            if (Plugin.__media === void 0) {
                Plugin.__media = window.matchMedia('(prefers-color-scheme: dark)')
                Plugin.__updateMedia = () => { Plugin.set('auto') }
                Plugin.__media.addListener(Plugin.__updateMedia)
            }

            val = Plugin.__media.matches
        }
        else if (Plugin.__media !== void 0) {
            Plugin.__media.removeListener(Plugin.__updateMedia)
            Plugin.__media = void 0
        }

        Plugin.isActive = val === true
        // 手动指定主题
        document.body.classList.remove(`body--${val === true ? 'light' : 'dark'}`)
        document.body.classList.add(`body--${val === true ? 'dark' : 'light'}`)
    },
    // 主题的切换
    toggle() {
        if (__QUASAR_SSR_SERVER__ !== true) {
            Plugin.set(Plugin.isActive === false)
        }
    },

    install({ $q, onSSRHydrated, ssrContext }) {
        const { dark } = $q.config

        if (__QUASAR_SSR_SERVER__) {
            this.isActive = dark === true

            $q.dark = {
                isActive: false,
                mode: false,
                set: val => {
                    ssrContext._meta.bodyClasses = ssrContext._meta.bodyClasses
                        .replace(' body--light', '')
                        .replace(' body--dark', '') + ` body--${val === true ? 'dark' : 'light'}`

                    $q.dark.isActive = val === true
                    $q.dark.mode = val
                },
                toggle: () => {
                    $q.dark.set($q.dark.isActive === false)
                }
            }

            $q.dark.set(dark)
            return
        }

        $q.dark = this

        if (this.__installed === true && dark === void 0) {
            return
        }

        this.isActive = dark === true

        const initialVal = dark !== void 0 ? dark : false

        if (isRuntimeSsrPreHydration.value === true) {
            const ssrSet = val => {
                this.__fromSSR = val
            }

            const originalSet = this.set

            this.set = ssrSet
            ssrSet(initialVal)

            onSSRHydrated.push(() => {
                this.set = originalSet
                this.set(this.__fromSSR)
            })
        }
        else {
            this.set(initialVal)
        }
    }
})

export default Plugin

<template>
    <el-button @click="toggleDark()">切换主题</el-button>
</template>

<script setup lang="ts">
    import { useDark, useToggle } from '@vueuse/core';

    const isDark = useDark();
    const toggleDark = useToggle(isDark);
</script>

<template>
  <n-config-provider :theme="theme">
    <n-card>
      <n-space>
        <n-button @click="theme = darkTheme">
          深色
        </n-button>
        <n-button @click="theme = null">
          浅色
        </n-button>
      </n-space>
    </n-card>
    <!-- 加上这个后可以切换全局主题 -->
    <n-global-style />
  </n-config-provider>
</template>

<script setup lang="ts">
import { ref } from 'vue'
import { darkTheme } from 'naive-ui'
import type { GlobalTheme } from 'naive-ui'

const theme = ref<GlobalTheme | null>(null)
</script>

<template>
  <n-config-provider :theme="theme">
    <n-card> 当前操作系统的主题是 {{ osTheme }}。 </n-card>
  </n-config-provider>
</template>

<script lang="ts">
import { defineComponent, computed } from 'vue'
import { useOsTheme, darkTheme } from 'naive-ui'

export default defineComponent({
  setup () {
    const osThemeRef = useOsTheme()
    return {
      theme: computed(() => (osThemeRef.value === 'dark' ? darkTheme : null)),
      osTheme: osThemeRef
    }
  }
})
</script>