如何从对象内部访问vuejs方法？(Vuejs 2)

const obj = {
  data() {
    return {
      message: 'Hello Vue.js'
    }
  },
  created() {
    setTimeout(() => {
      this.updateMessage() // 调用Vue实例的方法
    }, 1000)
  },
  methods: {
    updateMessage() {
      this.message = 'Updated message'
    }
  }
}

const obj = {
  data() {
    return {
      message: 'Hello Vue.js'
    }
  },
  created() {
    setTimeout(function() {
      this.updateMessage() // 调用Vue实例的方法
    }.bind(this), 1000)
  },
  methods: {
    updateMessage() {
      this.message = 'Updated message'
    }
  }
}

<template>
  <div>
    <button ref="myButton" @click="updateMessage">Click me</button>
  </div>
</template>

<script>
export default {
  data() {
    return {
      message: 'Hello Vue.js'
    }
  },
  methods: {
    updateMessage() {
      this.message = 'Updated message'
    },
    accessMethod() {
      this.$refs.myButton.click() // 调用按钮的点击方法
    }
  }
}
</script>