Vuex Vue2

When to use this skill

Use this skill whenever the user wants to:

• Install and set up Vuex in a Vue 2 project
• Manage application state with Vuex
• Use Vuex store in Vue components
• Understand Vuex core concepts (state, getters, mutations, actions)
• Use Vuex modules for large applications
• Handle Vuex plugins and devtools
• Understand Vuex API and methods
• Troubleshoot Vuex issues

How to use this skill

This skill is organized to match the Vuex official documentation structure (https://vuex.vuejs.org/zh/, https://vuex.vuejs.org/zh/guide/, https://vuex.vuejs.org/zh/api/). When working with Vuex:

1. Identify the topic from the user's request:

• Installation/安装 → examples/guide/installation.md
• Quick Start/快速开始 → examples/guide/quick-start.md
• Core Concepts/核心概念 → examples/core-concepts/
• Advanced/高级 → examples/advanced/
• API/API 文档 → api/

2. Load the appropriate example file from the examples/ directory:

Guide (使用指南):

• examples/guide/intro.md - Introduction to Vuex
• examples/guide/installation.md - Installation guide
• examples/guide/quick-start.md - Quick start guide
• examples/guide/what-is-vuex.md - What is Vuex

Core Concepts (核心概念):

• examples/core-concepts/state.md - State
• examples/core-concepts/getters.md - Getters
• examples/core-concepts/mutations.md - Mutations
• examples/core-concepts/actions.md - Actions
• examples/core-concepts/modules.md - Modules

Advanced (高级):

• examples/advanced/plugins.md - Plugins
• examples/advanced/strict-mode.md - Strict mode
• examples/advanced/form-handling.md - Form handling
• examples/advanced/testing.md - Testing
• examples/advanced/hot-reload.md - Hot reload

3. Follow the specific instructions in that example file for syntax, structure, and best practices

Important Notes:

• Vuex is for Vue 2.x
• Store is the central state management
• State is reactive
• Mutations are synchronous
• Actions are asynchronous
• Each example file includes key concepts, code examples, and key points

4. Reference API documentation in the api/ directory when needed:

• api/store-api.md - Store API
• api/state-api.md - State API
• api/getters-api.md - Getters API
• api/mutations-api.md - Mutations API
• api/actions-api.md - Actions API
• api/modules-api.md - Modules API
• api/plugins-api.md - Plugins API

5. Use templates from the templates/ directory:

• templates/installation.md - Installation templates
• templates/store-setup.md - Store setup templates
• templates/component-usage.md - Component usage templates

1. Understanding Vuex

Vuex is a state management pattern and library for Vue.js applications. It serves as a centralized store for all the components in an application.

Key Concepts:

• Store: Centralized state container
• State: Application state (data)
• Getters: Computed properties for store
• Mutations: Synchronous state changes
• Actions: Asynchronous operations
• Modules: Store organization

2. Installation

Using npm:

npm install vuex@3

Using yarn:

yarn add vuex@3

Using CDN:

<script src="https://unpkg.com/vuex@3"></script>

3. Basic Setup

// store/index.js
import Vue from 'vue'
import Vuex from 'vuex'

Vue.use(Vuex)

const store = new Vuex.Store({
  state: {
    count: 0
  },
  mutations: {
    increment(state) {
      state.count++
    }
  }
})

export default store

// main.js
import Vue from 'vue'
import store from './store'

new Vue({
  store,
  render: h => h(App)
}).$mount('#app')

Doc mapping (one-to-one with official documentation)

• examples/guide/ or examples/getting-started/ → https://vuex.vuejs.org/zh/guide/
• api/ → https://vuex.vuejs.org/zh/api/

Examples and Templates

This skill includes detailed examples organized to match the official documentation structure. All examples are in the examples/ directory (see mapping above).

To use examples:

• Identify the topic from the user's request
• Load the appropriate example file from the mapping above
• Follow the instructions, syntax, and best practices in that file
• Adapt the code examples to your specific use case

To use templates:

• Reference templates in templates/ directory for common scaffolding
• Adapt templates to your specific needs and coding style

API Reference

Detailed API documentation is available in the api/ directory, organized to match the official Vuex API documentation structure (https://vuex.vuejs.org/zh/api/):

Store API (api/store-api.md)

• Store constructor options
• Store instance properties
• Store instance methods

State API (api/state-api.md)

• State definition
• State access
• State reactivity

Getters API (api/getters-api.md)

• Getter definition
• Getter access
• Getter arguments

Mutations API (api/mutations-api.md)

• Mutation definition
• Mutation commit
• Mutation payload

Actions API (api/actions-api.md)

• Action definition
• Action dispatch
• Action context

Modules API (api/modules-api.md)

• Module definition
• Module namespacing
• Module registration

Plugins API (api/plugins-api.md)

• Plugin definition
• Plugin usage
• Built-in plugins

To use API reference: 1. Identify the API you need help with 2. Load the corresponding API file from the api/ directory 3. Find the API signature, parameters, return type, and examples 4. Reference the linked example files for detailed usage patterns 5. All API files include links to relevant example files in the examples/ directory

Best Practices

1. Use mutations for synchronous changes: Mutations must be synchronous 2. Use actions for async operations: Actions can contain async operations 3. Keep state normalized: Avoid nested state structures 4. Use modules for large apps: Organize store with modules 5. Use getters for computed state: Derive state with getters 6. Follow naming conventions: Use consistent naming patterns 7. Use TypeScript: Leverage TypeScript for type safety

Resources

• Official Documentation: https://vuex.vuejs.org/zh/
• Guide: https://vuex.vuejs.org/zh/guide/
• API Documentation: https://vuex.vuejs.org/zh/api/
• GitHub Repository: https://github.com/vuejs/vuex

Keywords

Vuex, vuex, Vue 2, state management, 状态管理, store, state, getters, mutations, actions, modules, 存储, 状态, 获取器, 变更, 动作, 模块, Vuex store, Vuex state, Vuex getters, Vuex mutations, Vuex actions, Vuex modules, Vuex plugins, centralized state, reactive state, synchronous mutations, asynchronous actions

能力边界

✅ 适用场景

• 当你需要使用此技能对应的技术栈时
• 当项目需要遵循最佳实践时
• 当需要快速上手或深入理解核心概念时

⚠️ 需要注意

• 复杂业务逻辑需要结合具体场景调整
• 性能优化需要根据实际数据量评估

❌ 不适用场景

• 不相关的技术栈或框架
• 需要完全自定义的特殊场景

常见陷阱 (Gotchas)

1. 版本兼容性：注意框架版本与依赖库的兼容性，不同版本 API 可能有差异 2. 配置文件格式：配置文件格式错误是最常见的问题，建议使用编辑器的语法检查 3. 环境变量：确保所有必要的环境变量已正确设置，敏感信息不要硬编码 4. 依赖冲突：多版本共存时注意依赖冲突，使用 lock 文件锁定版本 5. 性能陷阱：大数据量场景下注意性能优化，避免 N+1 查询等常见问题

使用流程

Step 1: 环境准备

确保开发环境已安装必要的依赖和工具。

Step 2: 配置初始化

根据项目需求进行基础配置。

Step 3: 核心功能使用

按照示例代码实现核心功能。

Step 4: 测试验证

运行测试确保功能正常。

Step 5: 部署上线

完成开发后进行部署和监控。

Actions API

API Reference

Vuex actions API.

Action Handler

actionHandler(context, payload)

• Action handler function
• Parameters:
• context: Action context object
• state: Local state
• getters: Local getters
• commit: Commit function
• dispatch: Dispatch function
• rootState: Root state
• rootGetters: Root getters
• payload: Action payload (optional)

Dispatch Method

store.dispatch(type, payload, options)

• Dispatch action
• Parameters:
• type: string - Action type
• payload: any - Action payload (optional)
• options: object - Options (optional)
• root: boolean - Dispatch to root (for namespaced modules)

Dispatch Examples

// String type
store.dispatch('increment')

// With payload
store.dispatch('fetchUser', userId)

// Object style
store.dispatch({
  type: 'fetchUser',
  userId: 1
})

// In namespaced module
store.dispatch('user/fetchUser', userId, { root: false })

Action Context Destructuring

actions: {
  async fetchData({ commit, state, dispatch, rootState }) {
    // Use context properties
  }
}

Action Rules

• Actions can be asynchronous
• Actions commit mutations
• Actions can dispatch other actions
• Actions can access root state/getters

See also: examples/core-concepts/actions.md for detailed examples

Getters API

API Reference

Vuex getters API.

Getter Definition

getter(state, getters, rootState, rootGetters)

• Getter function
• Parameters:
• state: Local state (module state if in module)
• getters: Local getters (module getters if in module)
• rootState: Root state (only in modules)
• rootGetters: Root getters (only in modules)

Getter Access

store.getters.getterName

• Access getter value
• Returns: Getter return value

Getter Examples

// Basic getter
getters: {
  doneTodos: state => {
    return state.todos.filter(todo => todo.done)
  }
}

// Getter with arguments (returns function)
getters: {
  getTodoById: state => id => {
    return state.todos.find(todo => todo.id === id)
  }
}

// Getter accessing other getters
getters: {
  doneTodos: state => state.todos.filter(todo => todo.done),
  doneTodosCount: (state, getters) => getters.doneTodos.length
}

Getter Access in Components

// Direct access
this.$store.getters.doneTodos

// With arguments
this.$store.getters.getTodoById(1)

// Using mapGetters
import { mapGetters } from 'vuex'
computed: {
  ...mapGetters(['doneTodos', 'doneTodosCount'])
}

Getter Rules

• Getters are cached
• Getters are computed properties
• Getters can access other getters
• Getters receive state and getters as arguments

See also: examples/core-concepts/getters.md for detailed examples

Modules API

API Reference

Vuex modules API.

Module Definition

interface Module {
  namespaced?: boolean
  state?: Object | Function
  getters?: Object
  mutations?: Object
  actions?: Object
  modules?: Object
}

Module Registration

Static Registration:

const store = new Vuex.Store({
  modules: {
    user: userModule,
    products: productsModule
  }
})

Dynamic Registration:

store.registerModule('user', userModule)

Module Namespacing

Namespaced Module:

const module = {
  namespaced: true,
  state: {},
  getters: {},
  mutations: {},
  actions: {}
}

Accessing Namespaced Module:

// State
store.state.moduleName.property

// Getters
store.getters['moduleName/getterName']

// Mutations
store.commit('moduleName/mutationName', payload)

// Actions
store.dispatch('moduleName/actionName', payload)

Module Context

In namespaced modules, context provides:

• state: Local module state
• getters: Local module getters
• commit: Local commit (namespaced)
• dispatch: Local dispatch (namespaced)
• rootState: Root state
• rootGetters: Root getters

Accessing Root

// Commit root mutation
commit('someMutation', null, { root: true })

// Dispatch root action
dispatch('someAction', null, { root: true })

See also: examples/core-concepts/modules.md for detailed examples

Mutations API

API Reference

Vuex mutations API.

Mutation Handler

mutationHandler(state, payload)

• Mutation handler function
• Parameters:
• state: Store state object
• payload: Mutation payload (optional)

Commit Method

store.commit(type, payload, options)

• Commit mutation
• Parameters:
• type: string - Mutation type
• payload: any - Mutation payload (optional)
• options: object - Options (optional)
• silent: boolean - Silent commit (no devtools)
• root: boolean - Commit to root (for namespaced modules)

Commit Examples

// String type
store.commit('increment')

// With payload
store.commit('increment', 10)

// Object style
store.commit({
  type: 'increment',
  amount: 10
})

// In namespaced module
store.commit('user/setName', 'John', { root: false })

Mutation Rules

• Mutations must be synchronous
• Mutations are the only way to change state
• Mutations are tracked by devtools
• Mutations should be pure functions

See also: examples/core-concepts/mutations.md for detailed examples

Store API

API Reference

Vuex Store constructor options and instance methods.

Store Constructor Options

state

• Type: Object | Function
• Description: Root state object or function returning state

getters

• Type: Object
• Description: Getter definitions

mutations

• Type: Object
• Description: Mutation definitions

actions

• Type: Object
• Description: Action definitions

modules

• Type: Object
• Description: Module definitions

plugins

• Type: Array<Function>
• Description: Plugin functions

strict

• Type: Boolean
• Default: false
• Description: Enable strict mode

devtools

• Type: Boolean
• Default: true
• Description: Enable devtools

Store Instance Properties

store.state

• Type: Object
• Description: Root state

store.getters

• Type: Object
• Description: Root getters

Store Instance Methods

store.commit(type, payload, options)

• Commit mutation
• Parameters: type - mutation type, payload - mutation payload, options - options

store.dispatch(type, payload, options)

• Dispatch action
• Parameters: type - action type, payload - action payload, options - options

store.replaceState(state)

• Replace store state
• Parameters: state - new state object

store.watch(getter, callback, options)

• Watch getter value
• Parameters: getter - getter function, callback - callback function, options - options

store.subscribe(callback)

• Subscribe to mutations
• Parameters: callback - callback function

store.subscribeAction(callback)

• Subscribe to actions
• Parameters: callback - callback function

store.registerModule(path, module, options)

• Register dynamic module
• Parameters: path - module path, module - module object, options - options

store.unregisterModule(path)

• Unregister dynamic module
• Parameters: path - module path

See also: examples/core-concepts/ for detailed usage examples

Plugins

官方文档: https://vuex.vuejs.org/zh/,

Instructions

This example demonstrates plugins usage in Vuex.

Key Concepts

• Plugin definition
• Plugin registration
• Plugin usage
• Built-in plugins

Example: Basic Plugin

// plugins/logger.js
const logger = store => {
  store.subscribe((mutation, state) => {
    console.log(mutation.type, mutation.payload)
    console.log('New state:', state)
  })
}

export default logger

Example: Registering Plugin

// store/index.js
import logger from './plugins/logger'

const store = new Vuex.Store({
  plugins: [logger],
  state: {
    count: 0
  }
})

Example: Plugin with Options

// plugins/logger.js
const logger = (store) => {
  store.subscribe((mutation, state) => {
    if (mutation.type.startsWith('user/')) {
      console.log('User mutation:', mutation.type)
    }
  })
}

export default logger

Example: State Persistence Plugin

// plugins/persist.js
const persist = (store) => {
  // Load state from localStorage
  const savedState = localStorage.getItem('vuex-state')
  if (savedState) {
    store.replaceState(JSON.parse(savedState))
  }
  
  // Save state to localStorage on mutation
  store.subscribe((mutation, state) => {
    localStorage.setItem('vuex-state', JSON.stringify(state))
  })
}

export default persist

Key Points

• Plugins are functions
• Plugins receive store instance
• Use subscribe for mutations
• Use replaceState for state replacement
• Register plugins in store options

Actions

官方文档: https://vuex.vuejs.org/zh/,

Instructions

This example demonstrates actions usage in Vuex.

Key Concepts

• Action definition
• Action dispatch
• Action context
• Asynchronous operations

Example: Basic Action

// store/index.js
const store = new Vuex.Store({
  state: {
    count: 0
  },
  mutations: {
    increment(state) {
      state.count++
    }
  },
  actions: {
    increment(context) {
      context.commit('increment')
    }
  }
})

Example: Action with Payload

actions: {
  incrementBy(context, payload) {
    context.commit('increment', payload)
  }
}

Example: Async Action

actions: {
  async fetchUser({ commit }, userId) {
    const response = await fetch(`/api/users/${userId}`)
    const user = await response.json()
    commit('setUser', user)
  }
}

Example: Action Context Destructuring

actions: {
  async fetchData({ commit, state, dispatch }) {
    const response = await fetch('/api/data')
    const data = await response.json()
    commit('setData', data)
    
    if (state.needsMore) {
      dispatch('fetchMore')
    }
  }
}

Example: Dispatching Actions

<template>
  <div>
    <button @click="increment">Increment</button>
    <button @click="fetchUser(1)">Fetch User</button>
  </div>
</template>

<script>
export default {
  methods: {
    increment() {
      this.$store.dispatch('increment')
    },
    fetchUser(userId) {
      this.$store.dispatch('fetchUser', userId)
    }
  }
}
</script>

Example: Using mapActions

<template>
  <div>
    <button @click="increment">Increment</button>
    <button @click="fetchUser(1)">Fetch User</button>
  </div>
</template>

<script>
import { mapActions } from 'vuex'

export default {
  methods: {
    ...mapActions(['increment', 'fetchUser'])
  }
}
</script>

Example: Action Returning Promise

actions: {
  fetchData({ commit }) {
    return new Promise((resolve, reject) => {
      fetch('/api/data')
        .then(response => response.json())
        .then(data => {
          commit('setData', data)
          resolve(data)
        })
        .catch(error => {
          reject(error)
        })
    })
  }
}

Key Points

• Actions can be asynchronous
• Dispatch actions via $store.dispatch
• Use mapActions helper
• Actions receive context object
• Actions commit mutations

Getters

官方文档: https://vuex.vuejs.org/zh/,

Instructions

This example demonstrates getters usage in Vuex.

Key Concepts

• Getter definition
• Getter access
• Getter arguments
• Computed properties

Example: Basic Getter

// store/index.js
const store = new Vuex.Store({
  state: {
    todos: [
      { id: 1, text: 'Todo 1', done: true },
      { id: 2, text: 'Todo 2', done: false }
    ]
  },
  getters: {
    doneTodos: state => {
      return state.todos.filter(todo => todo.done)
    }
  }
})

Example: Getter with Arguments

getters: {
  getTodoById: state => id => {
    return state.todos.find(todo => todo.id === id)
  }
}

Example: Getter Accessing Other Getters

getters: {
  doneTodos: state => {
    return state.todos.filter(todo => todo.done)
  },
  doneTodosCount: (state, getters) => {
    return getters.doneTodos.length
  }
}

Example: Accessing Getters in Components

<template>
  <div>
    <p>Done: {{ doneTodos.length }}</p>
  </div>
</template>

<script>
export default {
  computed: {
    doneTodos() {
      return this.$store.getters.doneTodos
    }
  }
}
</script>

Example: Using mapGetters

<template>
  <div>
    <p>Done: {{ doneTodos.length }}</p>
    <p>Count: {{ doneTodosCount }}</p>
  </div>
</template>

<script>
import { mapGetters } from 'vuex'

export default {
  computed: {
    ...mapGetters(['doneTodos', 'doneTodosCount'])
  }
}
</script>

Key Points

• Getters are computed properties
• Access via $store.getters
• Use mapGetters helper
• Getters are cached
• Can access other getters

Modules

官方文档: https://vuex.vuejs.org/zh/,

Instructions

This example demonstrates modules usage in Vuex.

Key Concepts

• Module definition
• Module namespacing
• Module state access
• Module mutations and actions

Example: Basic Module

// store/modules/user.js
const userModule = {
  state: {
    name: '',
    email: ''
  },
  mutations: {
    setName(state, name) {
      state.name = name
    }
  },
  actions: {
    fetchUser({ commit }) {
      // Fetch user data
      commit('setName', 'John')
    }
  }
}

export default userModule

Example: Registering Module

// store/index.js
import userModule from './modules/user'

const store = new Vuex.Store({
  modules: {
    user: userModule
  }
})

Example: Namespaced Module

// store/modules/user.js
const userModule = {
  namespaced: true,
  state: {
    name: ''
  },
  mutations: {
    setName(state, name) {
      state.name = name
    }
  },
  actions: {
    fetchUser({ commit }) {
      commit('setName', 'John')
    }
  }
}

Example: Accessing Namespaced Module

<template>
  <div>
    <p>{{ userName }}</p>
    <button @click="fetchUser">Fetch User</button>
  </div>
</template>

<script>
import { mapState, mapActions } from 'vuex'

export default {
  computed: {
    ...mapState('user', ['name']),
    userName() {
      return this.$store.state.user.name
    }
  },
  methods: {
    ...mapActions('user', ['fetchUser']),
    fetchUser() {
      this.$store.dispatch('user/fetchUser')
    }
  }
}
</script>

Example: Accessing Root State

// In namespaced module
actions: {
  someAction({ commit, state, rootState, rootGetters }) {
    // Access root state
    console.log(rootState.someRootState)
    
    // Access root getters
    console.log(rootGetters.someRootGetter)
    
    // Commit root mutation
    commit('someRootMutation', null, { root: true })
    
    // Dispatch root action
    dispatch('someRootAction', null, { root: true })
  }
}

Key Points

• Organize store with modules
• Use namespaced modules
• Access module state via namespace
• Access root state in modules
• Register modules in store

Mutations

官方文档: https://vuex.vuejs.org/zh/,

Instructions

This example demonstrates mutations usage in Vuex.

Key Concepts

• Mutation definition
• Mutation commit
• Mutation payload
• Synchronous mutations

Example: Basic Mutation

// store/index.js
const store = new Vuex.Store({
  state: {
    count: 0
  },
  mutations: {
    increment(state) {
      state.count++
    },
    decrement(state) {
      state.count--
    }
  }
})

Example: Mutation with Payload

mutations: {
  increment(state, payload) {
    state.count += payload.amount
  },
  setUser(state, user) {
    state.user = user
  }
}

Example: Committing Mutations

<template>
  <div>
    <button @click="increment">Increment</button>
    <button @click="incrementBy(10)">Increment by 10</button>
  </div>
</template>

<script>
export default {
  methods: {
    increment() {
      this.$store.commit('increment')
    },
    incrementBy(amount) {
      this.$store.commit('increment', { amount })
    }
  }
}
</script>

Example: Using mapMutations

<template>
  <div>
    <button @click="increment">Increment</button>
    <button @click="decrement">Decrement</button>
  </div>
</template>

<script>
import { mapMutations } from 'vuex'

export default {
  methods: {
    ...mapMutations(['increment', 'decrement'])
  }
}
</script>

Example: Object-Style Commit

this.$store.commit({
  type: 'increment',
  amount: 10
})

Key Points

• Mutations must be synchronous
• Commit mutations via $store.commit
• Use mapMutations helper
• Mutations receive state and payload
• Only way to change state

State

官方文档: https://vuex.vuejs.org/zh/,

Instructions

This example demonstrates state usage in Vuex.

Key Concepts

• State definition
• State access
• State reactivity
• Single source of truth

Example: State Definition

// store/index.js
const store = new Vuex.Store({
  state: {
    count: 0,
    todos: [],
    user: {
      name: '',
      email: ''
    }
  }
})

Example: Accessing State in Components

<template>
  <div>
    <p>Count: {{ count }}</p>
    <p>User: {{ user.name }}</p>
  </div>
</template>

<script>
export default {
  computed: {
    count() {
      return this.$store.state.count
    },
    user() {
      return this.$store.state.user
    }
  }
}
</script>

Example: Using mapState

<template>
  <div>
    <p>Count: {{ count }}</p>
    <p>Todos: {{ todos.length }}</p>
  </div>
</template>

<script>
import { mapState } from 'vuex'

export default {
  computed: {
    ...mapState(['count', 'todos'])
  }
}
</script>

Example: mapState with Object Syntax

<script>
import { mapState } from 'vuex'

export default {
  computed: {
    ...mapState({
      count: state => state.count,
      todos: state => state.todos,
      user: 'user'
    })
  }
}
</script>

Example: State as Function

// For module reuse
const moduleA = {
  state: () => ({
    count: 0
  })
}

Key Points

• State is reactive
• Access via $store.state
• Use mapState helper
• State can be object or function
• Single source of truth

Installation

官方文档: https://vuex.vuejs.org/zh/,

Instructions

This example demonstrates how to install Vuex.

Key Concepts

• Package installation
• CDN installation
• Vue plugin registration
• Version compatibility

Example: Package Installation

# Using npm
npm install vuex@3

# Using yarn
yarn add vuex@3

# Using pnpm
pnpm add vuex@3

Example: CDN Installation

<script src="https://unpkg.com/vuex@3"></script>

Example: Vue Plugin Registration

// main.js
import Vue from 'vue'
import Vuex from 'vuex'

Vue.use(Vuex)

Example: Store Creation

// store/index.js
import Vue from 'vue'
import Vuex from 'vuex'

Vue.use(Vuex)

const store = new Vuex.Store({
  state: {
    count: 0
  },
  mutations: {
    increment(state) {
      state.count++
    }
  }
})

export default store

Example: Store Integration

// main.js
import Vue from 'vue'
import store from './store'
import App from './App.vue'

new Vue({
  store,
  render: h => h(App)
}).$mount('#app')

Key Points

• Install vuex@3 for Vue 2
• Register Vuex as Vue plugin
• Create store instance
• Inject store into Vue instance
• Use store in components

Introduction

官方文档: https://vuex.vuejs.org/zh/,

Instructions

This example provides an introduction to Vuex.

Key Concepts

• What is Vuex
• Why use Vuex
• When to use Vuex
• Core concepts

Example: What is Vuex

Vuex is a state management pattern and library for Vue.js applications. It serves as a centralized store for all the components in an application.

Example: Why Use Vuex

• Centralized State: Single source of truth
• Predictable State Changes: State mutations are tracked
• DevTools Integration: Time-travel debugging
• Component Communication: Share state across components

Example: When to Use Vuex

Use Vuex when:

• Building large applications
• Multiple components share state
• Need to track state changes
• Complex state management required

Example: Core Concepts

• State: Application state (data)
• Getters: Computed properties for store
• Mutations: Synchronous state changes
• Actions: Asynchronous operations
• Modules: Store organization

Key Points

• Centralized state management
• Predictable state changes
• DevTools support
• Component communication
• Large application support

Quick Start

官方文档: https://vuex.vuejs.org/zh/,

Instructions

This example provides a quick start guide for Vuex.

Key Concepts

• Basic store setup
• State access
• Mutations
• Component usage

Example: Basic Store

// store/index.js
import Vue from 'vue'
import Vuex from 'vuex'

Vue.use(Vuex)

const store = new Vuex.Store({
  state: {
    count: 0
  },
  mutations: {
    increment(state) {
      state.count++
    },
    decrement(state) {
      state.count--
    }
  }
})

export default store

Example: Component Usage

<template>
  <div>
    <p>{{ count }}</p>
    <button @click="increment">+</button>
    <button @click="decrement">-</button>
  </div>
</template>

<script>
export default {
  computed: {
    count() {
      return this.$store.state.count
    }
  },
  methods: {
    increment() {
      this.$store.commit('increment')
    },
    decrement() {
      this.$store.commit('decrement')
    }
  }
}
</script>

Example: Using mapState

<template>
  <div>
    <p>{{ count }}</p>
  </div>
</template>

<script>
import { mapState } from 'vuex'

export default {
  computed: {
    ...mapState(['count'])
  }
}
</script>

Example: Using mapMutations

<template>
  <div>
    <button @click="increment">+</button>
    <button @click="decrement">-</button>
  </div>
</template>

<script>
import { mapMutations } from 'vuex'

export default {
  methods: {
    ...mapMutations(['increment', 'decrement'])
  }
}
</script>

Key Points

• Create store with state and mutations
• Access state via $store.state
• Commit mutations via $store.commit
• Use mapState and mapMutations helpers
• Inject store in Vue instance

What is Vuex

官方文档: https://vuex.vuejs.org/zh/,

Instructions

This example explains what Vuex is and its purpose.

Key Concepts

• State management pattern
• Centralized store
• Single source of truth
• Component communication

Example: State Management Problem

Without Vuex:

• Props drilling through multiple components
• Event bus for component communication
• Difficult to track state changes
• Hard to debug state issues

Example: Vuex Solution

With Vuex:

• Centralized state store
• Predictable state mutations
• DevTools integration
• Easy component communication

Example: Store Structure

const store = new Vuex.Store({
  state: {
    // Application state
  },
  getters: {
    // Computed properties
  },
  mutations: {
    // Synchronous state changes
  },
  actions: {
    // Asynchronous operations
  },
  modules: {
    // Store modules
  }
})

Example: Data Flow

Component → Dispatch Action → Commit Mutation → Update State → Component

Key Points

• Centralized state management
• Single source of truth
• Predictable mutations
• DevTools support
• Better component communication

Component Usage Templates

Accessing State

<template>
  <div>{{ count }}</div>
</template>

<script>
export default {
  computed: {
    count() {
      return this.$store.state.count
    }
  }
}
</script>

Using mapState

<template>
  <div>{{ count }}</div>
</template>

<script>
import { mapState } from 'vuex'

export default {
  computed: {
    ...mapState(['count'])
  }
}
</script>

Committing Mutations

<template>
  <button @click="increment">Increment</button>
</template>

<script>
export default {
  methods: {
    increment() {
      this.$store.commit('increment')
    }
  }
}
</script>

Using mapMutations

<template>
  <button @click="increment">Increment</button>
</template>

<script>
import { mapMutations } from 'vuex'

export default {
  methods: {
    ...mapMutations(['increment'])
  }
}
</script>

Dispatching Actions

<template>
  <button @click="fetchUser">Fetch User</button>
</template>

<script>
export default {
  methods: {
    fetchUser() {
      this.$store.dispatch('fetchUser', 1)
    }
  }
}
</script>

Using mapActions

<template>
  <button @click="fetchUser(1)">Fetch User</button>
</template>

<script>
import { mapActions } from 'vuex'

export default {
  methods: {
    ...mapActions(['fetchUser'])
  }
}
</script>

Store Setup Templates

Basic Store

// store/index.js
import Vue from 'vue'
import Vuex from 'vuex'

Vue.use(Vuex)

const store = new Vuex.Store({
  state: {
    count: 0
  },
  mutations: {
    increment(state) {
      state.count++
    }
  }
})

export default store

Store with All Features

// store/index.js
import Vue from 'vue'
import Vuex from 'vuex'
import userModule from './modules/user'

Vue.use(Vuex)

const store = new Vuex.Store({
  state: {
    count: 0
  },
  getters: {
    doubleCount: state => state.count * 2
  },
  mutations: {
    increment(state) {
      state.count++
    }
  },
  actions: {
    incrementAsync({ commit }) {
      setTimeout(() => {
        commit('increment')
      }, 1000)
    }
  },
  modules: {
    user: userModule
  }
})

export default store

Module Template

// store/modules/user.js
const userModule = {
  namespaced: true,
  state: {
    name: '',
    email: ''
  },
  getters: {
    fullName: state => `${state.name} (${state.email})`
  },
  mutations: {
    setName(state, name) {
      state.name = name
    }
  },
  actions: {
    fetchUser({ commit }, userId) {
      // Async operation
      commit('setName', 'John')
    }
  }
}

export default userModule