.vue

<template>
  <div>
    还剩{{balance}}
    <button @click="handleClick">我要花我爷爷给我的钱</button>
  </div>
</template>

<script>
export default {
  inject: ['eventBus'],
  props: ['balance'],
  methods: {
    handleClick() {
      this.eventBus.$emit('我想花钱', 100)
    }
  }
}
</script>