Home Vue

# MyHeader

  • components/MyHeader
vue
<template>
  <div class="todo-header">
    <input
      type="text"
      placeholder="请输入你的任务名称，按回车键确认"
      v-model="title"
      @keyup.enter="add"
    />
  </div>
</template>
<script>
import { nanoid } from "nanoid";
export default {
  name: "MyHeader",
  data() {
    return {
      // 收集用户输入的 title
      title: "",
    };
  },
  methods: {
    add() {
      // 校验数据
      if (!this.title.trim()) return alert("输入不能为空");
      // 将用户的输入包装成一个 todo 对象
      const todo = { id: nanoid(), title: this.title, done: false };
      // 通知 App 组件去添加一个 todo 对象
      this.$emit("addTodo", todo);
      // 清空输入
      this.title = "";
    },
  },
};
</script>
<style scoped>
/*header*/
.todo-header input {
  width: 560px;
  height: 28px;
  font-size: 14px;
  border: 1px solid #ccc;
  border-radius: 4px;
  padding: 4px 7px;
}
.todo-header input:focus {
  outline: none;
  border-color: rgba(82, 168, 236, 0.8);
  box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075),
    0 0 8px rgba(82, 168, 236, 0.6);
}
</style>
# MyList


vue
<template>
  <ul class="todo-main">
    <transition-group name="todo" appear>
      <MyItem v-for="todo in todos" :key="todo.id" :todo="todo" />
    </transition-group>
  </ul>
</template>
<script>
import MyItem from "./MyItem";
export default {
  name: "MyList",
  components: { MyItem },
  // 声明接收 App 传递过来的数据
  props: ["todos"],
};
</script>
<style scoped>
/*main*/
.todo-main {
  margin-left: 0px;
  border: 1px solid #ddd;
  border-radius: 2px;
  padding: 0px;
  overflow: hidden;
}
.todo-empty {
  height: 40px;
  line-height: 40px;
  border: 1px solid #ddd;
  border-radius: 2px;
  padding-left: 5px;
  margin-top: 10px;
}
.todo-enter-active {
  animation: td 0.5s linear;
}
.todo-leave-active {
  animation: td 0.5s linear reverse;
}
@keyframes td {
  from {
    transform: translateX(100%);
  }
  to {
    transform: translateX(0);
  }
}
</style>
# MyItem


    

  • components/MyItem
    • 



vue
<template>
  <li>
    <label>
      <input
        type="checkbox"
        :checked="todo.done"
        @change="handleCheck(todo.id)"
      />	
      <!-- 如下代码也能实现功能，但是不太推荐，因为有点违反原则，因为修改了props -->
      <!-- <input type="checkbox" v-model="todo.done"/> -->
      <span v-show="!todo.isEdit"><!--swig0--></span>
      <input
        type="text"
        v-show="todo.isEdit"
        :value="todo.title"
        @blur="handleBlur(todo, $event)"
        ref="inputTitle"
      />
    </label>
    <button class="btn btn-danger" @click="handleDelete(todo.id)">删除</button>
    <button
      v-show="!todo.isEdit"
      class="btn btn-edit"
      @click="handleEdit(todo)"
    >
      编辑
    </button>
  </li>
</template>
<script>
export default {
  name: "MyItem",
  // 声明接收 todo
  props: ["todo"],
  methods: {
    // 勾选 or 取消勾选
    handleCheck(id) {
      // 通知 App 组件将对应的 todo 对象的 done 值取反
      // this.checkTodo(id)
      this.$bus.$emit("checkTodo", id);
    },
    // 删除
    handleDelete(id) {
      if (confirm("确定删除吗？")) {
        // 通知 App 组件将对应的 todo 对象删除
        // this.deleteTodo(id)
        this.$bus.$emit("deleteTodo", id);
      }
    },
    handleEdit(todo) {
      if (Object.prototype.hasOwnProperty.call(todo, "isEdit")) {
        todo.isEdit = true;
      } else {
        this.$set(todo, "isEdit", true);
      }
      this.$nextTick(function () {
        this.$refs.inputTitle.focus();
      });
    },
    handleBlur(todo, e) {
      this.$bus.$emit("updateTodo", todo.id, e.target.value);
      todo.isEdit = false;
    },
  },
};
</script>
<style scoped>
/*item*/
li {
  list-style: none;
  height: 36px;
  line-height: 36px;
  padding: 0 5px;
  border-bottom: 1px solid #ddd;
}
li label {
  float: left;
  cursor: pointer;
}
li label li input {
  vertical-align: middle;
  margin-right: 6px;
  position: relative;
  top: -1px;
}
li button {
  float: right;
  display: none;
  margin-top: 3px;
}
li:before {
  content: initial;
}
li:last-child {
  border-bottom: none;
}
li:hover {
  background-color: #ddd;
}
li:hover button {
  display: block;
}
</style>
# MyFooter


    

  • components/MyHeader
    • 



<template>
  <div class="todo-footer" v-show="total">
    <label>
      <!-- <input type="checkbox" :checked="isAll" @change="checkAll"/> -->
      <input type="checkbox" v-model="isAll" />
    </label>
    <span>
      <span>已完成{{ doneTotal }}</span> / 全部{{ total }}
    </span>
    <button class="btn btn-danger" @click="clearAll">清除已完成任务</button>
  </div>
</template>

<script>
export default {
  name: "MyFooter",
  props: ["todos"],
  computed: {
    //总数
    total() {
      return this.todos.length;
    },
    //已完成数
    doneTotal() {
      //此处使用reduce方法做条件统计
      /* const x = this.todos.reduce((pre,current)=>{
					console.log('@',pre,current)
					return pre + (current.done ? 1 : 0)
				},0) */
      //简写
      return this.todos.reduce((pre, todo) => pre + (todo.done ? 1 : 0), 0);
    },
    //控制全选框
    isAll: {
      //全选框是否勾选
      get() {
        return this.doneTotal === this.total && this.total > 0;
      },
      //isAll被修改时set被调用
      set(value) {
        // this.checkAllTodo(value)
        this.$emit("checkAllTodo", value);
      },
    },
  },
  methods: {
    /* checkAll(e){
				this.checkAllTodo(e.target.checked)
			} */
    //清空所有已完成
    clearAll() {
      // this.clearAllTodo()
      this.$emit("clearAllTodo");
    },
  },
};
</script>

<style scoped>
/*footer*/
.todo-footer {
  height: 40px;
  line-height: 40px;
  padding-left: 6px;
  margin-top: 5px;
}

.todo-footer label {
  display: inline-block;
  margin-right: 20px;
  cursor: pointer;
}

.todo-footer label input {
  position: relative;
  top: -1px;
  vertical-align: middle;
  margin-right: 5px;
}

.todo-footer button {
  float: right;
  margin-top: 5px;
}
</style>



# App


vue
<template>
  <div id="app">
    <div id="root">
      <div class="todo-container">
        <div class="todo-wrap">
          <MyHeader @addTodo="addTodo"></MyHeader>
          <MyList :todos="todos"> </MyList>
          <MyFooter
            :todos="todos"
            @checkAllTodo="checkAllTodo"
            @clearAllTodo="clearAllTodo"
          ></MyFooter>
        </div>
      </div>
    </div>
  </div>
</template>
<script>
import MyHeader from "@/components/MyHeader";
import MyFooter from "./components/MyFooter.vue";
import MyList from "@/components/MyList";
export default {
  name: "App",
  components: {
    MyHeader,
    MyFooter,
    MyList,
  },
  data() {
    return {
      todos: JSON.parse(localStorage.getItem("todos")) || [],
    };
  },
  methods: {
    addTodo(x) {
      this.todos.unshift(x);
    },
    checkTodo(id) {
      this.todos.forEach((todo) => {
        if (todo.id === id) todo.done = !todo.done;
      });
    },
    deleteTodo(id) {
      this.todos = this.todos.filter((todo) => todo.id !== id);
    },
    checkAllTodo(done) {
      console.log(done);
      this.todos.forEach((todo) => (todo.done = done));
    },
    clearAllTodo() {
      if (confirm("确定要清除所有已完成的吗？")) {
        this.todos = this.todos.filter((todo) => !todo.done);
      }
    },
    updateTodo(id, title) {
      this.todos.forEach((todo, i) => {
        if (todo.id === id) {
          if (!title) {
            if (confirm("内容为空是否进行删除？")) {
              this.todos.splice(this.todos[i], 1);
            }
          }
          todo.title = title;
        }
      });
    },
  },
  watch: {
    todos: {
      deep: true,
      handler(val) {
        localStorage.setItem("todos", JSON.stringify(val));
      },
    },
  },
  mounted() {
    this.$bus.$on("checkTodo", this.checkTodo);
    this.$bus.$on("updateTodo", this.updateTodo);
    this.$bus.$on("deleteTodo", this.deleteTodo);
  },
  beforeDestroy() {
    this.$bus.$off("checkTodo");
    this.$bus.$off("updateTodo");
    this.$bus.$off("deleteTodo");
  },
};
</script>
<style>
/*base*/
body {
  background: #fff;
}
.btn {
  display: inline-block;
  padding: 4px 12px;
  margin-bottom: 0;
  font-size: 14px;
  line-height: 20px;
  text-align: center;
  vertical-align: middle;
  cursor: pointer;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.2),
    0 1px 2px rgba(0, 0, 0, 0.05);
  border-radius: 4px;
}
.btn-danger {
  color: #fff;
  background-color: #da4f49;
  border: 1px solid #bd362f;
}
.btn-edit {
  color: #fff;
  background-color: skyblue;
  border: 1px solid rgb(103, 159, 180);
  margin-right: 5px;
}
.btn-danger:hover {
  color: #fff;
  background-color: #bd362f;
}
.btn:focus {
  outline: none;
}
.todo-container {
  width: 600px;
  margin: 0 auto;
}
.todo-container .todo-wrap {
  padding: 10px;
  border: 1px solid #ddd;
  border-radius: 5px;
}
</style>
# main


import Vue from 'vue'
import App from './App.vue'
Vue.config.productionTip = false
new Vue({
  render: h => h(App),
  beforeCreate() {
    Vue.prototype.$bus = this
  }
}).$mount('#app')
# 总结 TodoList 案例


    

  1. 

    组件化编码流程：
    

    ​	(1). 拆分静态组件：组件要按照功能点拆分，命名不要与 html 元素冲突。
    

    ​	(2). 实现动态组件：考虑好数据的存放位置，数据是一个组件在用，还是一些组件在用：
    

    ​			1). 一个组件在用：放在组件自身即可。
    

    ​			2). 一些组件在用：放在他们共同的父组件上（<span style="color:red"> 状态提升 </span>）。
    

    ​	(3). 实现交互：从绑定事件开始。
    

    2. 

  2. 

    props 适用于：
    

    ​	(1). 父组件 ==> 子组件 通信
    

    ​	(2). 子组件 ==> 父组件 通信（要求父先给子一个函数）
    

    3. 

  3. 

    使用 v-model 时要切记：v-model 绑定的值不能是 props 传过来的值，因为 props 是不可以修改的！
    

    4. 

  4. 

    props 传过来的若是对象类型的值，修改对象中的属性时 Vue 不会报错，但不推荐这样做。
    

    5. 



      

          
      

  


   


    

  
    
      
    
    Update on
    
  
  
      
        
      
      Views
      
      times
  



      


  
  
Give me a cup of [coffee]~(￣▽￣)~*

  

      
      

        Nico Niconi WeChat Pay
        
WeChat Pay

      

      
      

        Nico Niconi Alipay
        
Alipay