Vue.js: Componentes Dinâmicos e Assíncronos

<!-- ❌ The "Broken" Version: 5 Tabs with 5 v-if -->
<template>
  <div class="tabs">
    <button @click="currentTab = 'home'">Home</button>
    <button @click="currentTab = 'profile'">Profile</button>
    <button @click="currentTab = 'settings'">Settings</button>
    
    <div v-if="currentTab === 'home'">
      <HomeTab />
    </div>
    <div v-else-if="currentTab === 'profile'">
      <ProfileTab />
    </div>
    <div v-else-if="currentTab === 'settings'">
      <SettingsTab />
    </div>
  </div>
</template>

<!-- ✅ Correct Version: 1 <component> Switch -->
<template>
  <div class="tabs">
    <button 
      v-for="tab in tabs" 
      :key="tab.name"
      :class="{ active: currentTab === tab.name }"
      @click="currentTab = tab.name"
    >
      {{ tab.label }}
    </button>
    
    <!-- ✅ 1 <component> Dynamic Tag Switching -->
    <component :is="currentTabComponent" />
  </div>
</template>

<script setup>
import { ref, computed, defineAsyncComponent } from 'vue'

// Synchronization Components
import HomeTab from './tabs/HomeTab.vue'
import ProfileTab from './tabs/ProfileTab.vue'

// Asynchronous Components(Laden on Demand)
const SettingsTab = defineAsyncComponent(() => import('./tabs/SettingsTab.vue'))

const tabs = [
  { name: 'home', label: 'Home' },
  { name: 'profile', label: 'Profile' },
  { name: 'settings', label: 'Settings' }
]

const currentTab = ref('home')

// Computed Properties:According to currentTab Determine which component to display
const currentTabComponent = computed(() => {
  return { home: HomeTab, profile: ProfileTab, settings: SettingsTab }[currentTab.value]
})
</script>

<!-- Writing Style 1:Component Name String(Registered globally) -->
<component :is="'HomeTab'" />

<!-- Writing Style 2:Component Object(Most Commonly Used) -->
<component :is="HomeTab" />

<!-- Writing Style 3:Dynamically Calculated Properties -->
<component :is="currentTabComponent" />

<!-- Writing Style 4:Asynchronous Component Object -->
<component :is="asyncComponent" />

<!-- Writing Style 5:Inline Component Object -->
<component :is="{ template: '<div>Inline</div>' }" />

<!-- TabContainer.vue -->
<template>
  <div>
    <button 
      v-for="tab in tabs" 
      :key="tab.name"
      @click="currentTab = tab.name"
    >
      {{ tab.label }}
    </button>
    
    <!-- Dynamic Components -->
    <component :is="currentTabComponent" />
  </div>
</template>

<script setup>
import { ref, computed } from 'vue'
import HomeTab from './tabs/HomeTab.vue'
import ProfileTab from './tabs/ProfileTab.vue'
import SettingsTab from './tabs/SettingsTab.vue'

const tabs = [
  { name: 'home', label: 'Home' },
  { name: 'profile', label: 'Profile' },
  { name: 'settings', label: 'Settings' }
]

const currentTab = ref('home')

const currentTabComponent = computed(() => ({
  home: HomeTab,
  profile: ProfileTab,
  settings: SettingsTab
}[currentTab.value]))
</script>

<script setup>
import { defineAsyncComponent } from 'vue'
import LoadingSpinner from './LoadingSpinner.vue'

// Asynchronous Components:Only when using ChartEditor Load its code only when needed
const ChartEditor = defineAsyncComponent({
  // 1. Load Function
  loader: () => import('./ChartEditor.vue'),
  
  // 2. Display while loading
  loadingComponent: LoadingSpinner,
  
  // 3. Display when loading fails
  errorComponent: ErrorMessage,
  
  // 4. Load Delay(Prevent Flickering)
  delay: 200
})
</script>

<template>
  <ChartEditor v-if="showEditor" />
</template>

<script setup>
import { defineAsyncComponent } from 'vue'

// ✅ Simplified Version:Only loader
const ChartEditor = defineAsyncComponent(() => import('./ChartEditor.vue'))
</script>

<template>
  <!-- Suspense Automatically wait for asynchronous components to finish loading -->
  <Suspense>
    <!-- Asynchronous Components -->
    <ChartEditor :data="chartData" />
    
    <!-- Display while loading(Default Slot) -->
    <template #fallback>
      <LoadingSpinner />
    </template>
  </Suspense>
</template>

<template>
  <Suspense>
    <!-- Default Slot:Asynchronous Content -->
    <AsyncComponent />
    
    <!-- Fallback Slot: Display while loading -->
    <template #fallback>
      <div>Loading...</div>
    </template>
  </Suspense>
</template>

<template>
  <component :is="currentTabComponent" />
</template>

<!-- Switch Tab:
1. Legacy Components onBeforeUnmount
2. Legacy Components onUnmounted
3. New Component onBeforeMount
4. New Component onMounted
5. Data is reloaded every time you switch(Poor performance)
-->

<template>
  <keep-alive>
    <component :is="currentTabComponent" />
  </keep-alive>
</template>

<!-- Switch Tab:
1. Legacy Components onDeactivated(Destroy without stopping)
2. New Component onActivated(Restore from Cache)
3. Data Retention,Scroll Position Retention
-->

<template>
  <!-- include:Cache only the specified components -->
  <keep-alive include="HomeTab,ProfileTab">
    <component :is="currentTabComponent" />
  </keep-alive>
  
  <!-- exclude:Do not cache the specified component -->
  <keep-alive exclude="SettingsTab">
    <component :is="currentTabComponent" />
  </keep-alive>
  
  <!-- max: Maximum 5 Cached -->
  <keep-alive :max="5">
    <component :is="currentTabComponent" />
  </keep-alive>
</template>

<template>
  <div>
    <nav>
      <button
        v-for="tab in tabs"
        :key="tab.name"
        :class="{ active: currentTab === tab.name }"
        @click="currentTab = tab.name"
      >
        {{ tab.label }}
      </button>
    </nav>
    
    <component :is="currentTabComponent" />
  </div>
</template>

<script setup>
import { ref, computed } from 'vue'
import HomeTab from './tabs/HomeTab.vue'
import ProfileTab from './tabs/ProfileTab.vue'

const tabs = [
  { name: 'home', label: 'Home' },
  { name: 'profile', label: 'Profile' },
  { name: 'settings', label: 'Settings' }
]
const currentTab = ref('home')

const currentTabComponent = computed(() => ({
  home: HomeTab,
  profile: ProfileTab,
  settings: SettingsTab
}[currentTab.value]))
</script>

<!-- App.vue -->
<template>
  <button @click="show = !show">Toggle</button>
  
  <Suspense v-if="show">
    <!-- Asynchronous Components(Do not load on the first screen,Load only when clicked) -->
    <HeavyChart :data="data" />
    
    <template #fallback>
      <div>Loading chart...</div>
    </template>
  </Suspense>
</template>

<script setup>
import { ref, defineAsyncComponent } from 'vue'

const show = ref(false)

// ✅ Asynchronous Components:News import,Laden on Demand
const HeavyChart = defineAsyncComponent(() => import('./HeavyChart.vue'))
const data = ref([1, 2, 3, 4, 5])
</script>

<template>
  <div>
    <button v-for="tab in tabs" @click="currentTab = tab.name">
      {{ tab.label }}
    </button>
    
    <!-- keep-alive Cache: Preserve data when switching -->
    <keep-alive :max="3">
      <component :is="currentTabComponent" />
    </keep-alive>
  </div>
</template>