vue3.0 组合式(Composition)API TodoList

1.vue3.0允许在template里写多个根组件

效果：

目录结构：

TodoList.vue:

<template>
  <Header @onAdd="handleAdd"></Header>
  <List
    :list="state.list"
    @onChecked="handleChecked"
    @onDelete="handleDelete"
  ></List>
</template>

<script>
import { reactive } from "vue";
import Header from "../components/Header";
import List from "../components/List";

export default {
  components: {
    Header,
    List,
  },
  setup() {
    const state = reactive({
      list: [],
    });

    const handleAdd = (title) => {
      state.list.push({
        id: Date.now(),
        title,
        done: false,
      });
    };

    const handleChecked = (payload) => {
      let index = state.list.findIndex((item) => item.id === payload.id);
      state.list[index].done = payload.checked;
    };

    const handleDelete = (payload) => {
      state.list = state.list.filter((item) => item.id !== payload.id);
    };

    return {
      state,
      handleAdd,
      handleChecked,
      handleDelete,
    };
  },
};
</script>

<style>
</style>

Header.vue:

<template>
  <div>
    <input type="text" :value="title" @input="handleTitle" @keyup.enter="handleAdd" autofocus placeholder="请输入">
  </div>
</template>

<script>
import { ref } from 'vue'

export default {
  emits: ['onAdd'],
  setup(props, context) {
    const title = ref('')
    const handleTitle = (e) => {
      title.value = e.target.value
    }

    const handleAdd = () => {
      context.emit('onAdd', title.value)
      title.value = ''
    }

    return {
      title,
      handleTitle,
      handleAdd
    }
  }
}
</script>

<style>

</style>

List.vue:

<template>
  <div>正在进行({{ doningList.length }})</div>
  <ListItem
    v-for="item in doningList"
    :key="item.id"
    :item="item"
    @onChecked="handleChecked"
    @onDelete="handleDelete"
  ></ListItem>
  <div>已经完成({{ doneList.length }})</div>
  <ListItem
    v-for="item in doneList"
    :key="item.id"
    :item="item"
    @onChecked="handleChecked"
    @onDelete="handleDelete"
  ></ListItem>
</template>

<script>
import { computed } from "vue";
import ListItem from "./ListItem";

export default {
  props: ["list"],
  components: {
    ListItem,
  },
  setup(props, context) {
    const doningList = computed(() => {
      return props.list.filter((item) => !item.done);
    });

    const doneList = computed(() => props.list.filter((item) => item.done));

    const handleChecked = (payload) => {
      context.emit("onChecked", payload);
    };

    const handleDelete = (payload) => context.emit("onDelete", payload);

    return {
      doningList,
      doneList,
      handleChecked,
      handleDelete,
    };
  },
};
</script>

<style>
</style>

ListItem.vue:

<template>
  <div>
    <input type="checkbox" :id="item.id" :checked="item.done" @change="handleChange"/>
    <label :for="item.id">{{item.title}}</label>
    <button @click="handleDelete">删除</button>
  </div>
</template>

<script>
export default {
  props: ['item'],
  setup(props, context) {
    const handleChange = (e) => {
      context.emit('onChecked', { id: props.item.id, checked: e.target.checked })
    }

    const handleDelete = () => {
      context.emit('onDelete', { id : props.item.id })
    }
    return {
      handleChange,
      handleDelete
    }
  }
}
</script>

<style>

</style>

参考链接：

​​http://www.todolist.cn/​​