Vue源码学习之初始化模块init.js解析

2.initEvents

function initEvents (vm: Component) {
 vm._events = Object.create(null)
 vm._hasHookEvent = false
 // init parent attached events
 const listeners = vm.$options._parentListeners
 if (listeners) {
  updateComponentListeners(vm, listeners)
 }
}

又新增两个属性，后面那个if条件里面是有父组件的事件时初始化，估计就是props和events父子组件通信的事件内容。

3.initRender

function initRender (vm: Component) {
 vm._vnode = null // the root of the child tree
 vm._staticTrees = null
 const parentVnode = vm.$vnode = vm.$options._parentVnode
 const renderContext = parentVnode && parentVnode.context
 vm.$slots = resolveSlots(vm.$options._renderChildren, renderContext)
 vm.$scopedSlots = emptyObject
 vm._c = (a, b, c, d) => createElement(vm, a, b, c, d, false)
 vm.$createElement = (a, b, c, d) => createElement(vm, a, b, c, d, true)
 const parentData = parentVnode && parentVnode.data
 /* istanbul ignore else */
 if (process.env.NODE_ENV !== 'production') {
  defineReactive(vm, '$attrs', parentData && parentData.attrs, () => {
   !isUpdatingChildComponent && warn(`$attrs is readonly.`, vm)
  }, true)
  defineReactive(vm, '$listeners', vm.$options._parentListeners, () => {
   !isUpdatingChildComponent && warn(`$listeners is readonly.`, vm)
  }, true)
 } else {
  defineReactive(vm, '$attrs', parentData && parentData.attrs, null, true)
  defineReactive(vm, '$listeners', vm.$options._parentListeners, null, true)
 }
}

此函数也是初始化了节点属性信息，绑定createElement函数到实例【并未挂载】，接下来调用beforeCreate回调钩子；——TODO1：后续专题分析VUE渲染逻辑

4.initInjections

function initInjections (vm: Component) {
 const result = resolveInject(vm.$options.inject, vm)
 if (result) {
  observerState.shouldConvert = false
  Object.keys(result).forEach(key => {
   /* istanbul ignore else */
   if (process.env.NODE_ENV !== 'production') {
    defineReactive(vm, key, result[key], () => {
     warn(
      `Avoid mutating an injected value directly since the changes will be ` +
      `overwritten whenever the provided component re-renders. ` +
      `injection being mutated: "${key}"`,
      vm
     )
    })
   } else {
    defineReactive(vm, key, result[key])
   }
  })
  observerState.shouldConvert = true
 }
}

此函数也是当有inject属性时做处理，源码例子无inject断点跑暂时跳过

5.initState

								 
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