VIP30/v3_project/15_provide和inject/App.vue

<template>
  <h2>provide 和 inject</h2>
  <p>当前的颜色: {{ color }}</p>
  <button @click="color='red'">红色</button>
  <button @click="color='yellow'">黄色</button>
  <button @click="color='green'">绿色</button>
  <hr>
  <Child></Child>
</template>

<script lang="ts">
import { defineComponent, provide, ref } from "vue";
import Child from "./components/Child.vue"
export default defineComponent({
  //实现跨层级组件(祖孙)之间通信
  setup() {
    const color = ref("red");
    provide('color',color)
    return {
      color,
    };
  },
  components: {
    Child
  }
});
</script>

<style scoped>
</style>