如果我们在vuejs中单击菜单外部，如何隐藏下拉菜单

I am using a dropdown menu components in vuejs to make normal dropdown menu. My code is for dropdown component is :

<template>
    <span class="dropdown" :class="{shown: state}">
        <a href="#" @click.prevent="toggleDropdown" class="dropdown-toggle">toggle menu</a>
            <div class="dropdown-menu" v-show="state">
                <ul class="list-unstyled">
                    <slot></slot>
                </ul>
            </div>
        </transition>
    </span>
</template>

<script>
export default {
    name: 'dropdown',
    data () {
        return {
            state: false
        }
    },
    methods: {
        toggleDropdown (e) {
            this.state = !this.state;
        }
    }
}
</script>

Now I am importing the dropdown component in my VUE app at various place by using following code in the template

<dropdown>
    <li>
         Action
    </li>
</dropdown>

Now that is working fine but I want that only one dropdown should be active at the same time.

I have done little research and found that i can use plugins like https://github.com/davidnotplay/vue-my-dropdown but I don't want to use that. Again i have also studied how the above example works but I want to implement this dropdown functionality in such a way that my dropdown component would take care of all event related to dropdown. So can you help me how to achieve that?

解决方案

I know it's quite an old question but I think the best way to do that without any external plugins is to add a click listener to mounted lifecycle hook (and remove it on beforeDestroy hook) and filter the clicks on your component so it only hides when clicked outside.

<template>
    <span class="dropdown" :class="{shown: state}">
      <a href="#" @click.prevent="toggleDropdown" class="dropdown-toggle">toggle menu</a>
            <div class="dropdown-menu" v-show="state">
                <ul class="list-unstyled">
                    <slot></slot>
                </ul>
            </div>
        <transition/>
    </span>
</template>

<script>
export default {
  name: 'dropdown',
  data () {
    return {
      state: false
    }
  },
  methods: {
    toggleDropdown (e) {
      this.state = !this.state
    },
    close (e) {
      if (!this.$el.contains(e.target)) {
        this.state = false
      }
    }
  },
  mounted () {
    document.addEventListener('click', this.close)
  },
  beforeDestroy () {
    document.removeEventListener('click',this.close)
  }
}
</script>