How to write a global notice component?

The following will achieve this effect ：

1. Component dynamic creation script ：

   NotificationBanner.js

   import Vue from "vue";
   import Notice from "@/components/Noticer/Notice.vue";
   
   function create(Component, props) {
     //  Create an instance first 
     const vm = new Vue({
       render(h) {
         //h Namely createElement, It returns VNode
         return h(Component, { props });
       },
     }).$mount();
     //  Manual mount 
   
     //  Judge whether it exists container, If it does not exist, create 
     let container;
     container = document.querySelector(".noticer-container");
     if (container == null) {
       container = document.createElement("div");
       container.classList.add("noticer-container");
       container.style.position = "fixed";
       container.style.top = "50px";
       container.style.right = "0px";
       container.style.overflow = "hidden";
       container.style.zIndex = 9999;
   
       document.body.appendChild(container);
     }
   
     container.appendChild(vm.$el);
   
     // Destruction method 
     const comp = vm.$children[0];
     comp.remove = function () {
       container.removeChild(comp["$el"]);
       vm.$destroy();
     };
     comp.show();
     return comp;
   }
   
   Vue.prototype.$notice = {
     error: function (props) {
       create(Notice, Object.assign(props, { type: "error" }));
     },
     info: function (props) {
       create(Notice, Object.assign(props, { type: "info" }));
     },
     success: function (props) {
       create(Notice, Object.assign(props, { type: "success" }));
     },
     warn: function (props) {
       create(Notice, Object.assign(props, { type: "warn" }));
     },
   };
   
   

   Here are some things worth noting ：

   1. container： The role of is notice The container of , It can be used to locate notice Where on the page , Be careful notice Should not scroll with the page , Therefore, its positioning is fixed, The reason why it is set to overflow:hidden The reason is ,notice When appearing and removing , The animation offset occurred , Will make the page appear horizontal scroll bar . To avoid duplicate creation container, Here is a judgment logic . Then all dynamically generated notice example dom Will pass appendChild Add to this container .
   2. When removed , What was removed was vm.$children[0]["$el"] , as a result of ,Notice Implementation of the template , The outer layer is covered with a transition , And this transition It doesn't render dom Of .

2. establish Notice Component template ：

   Component template

   <template>
     <transition
       enter-active-class="animate__animated animate__slideInRight"
       leave-active-class="animate__animated animate__slideOutRight"
       @after-leave="afterLeave"
     >
       <div v-if="isShow" class="notice__root">
         <div :class="`notice-type-${type}`" class="noticer">
           {{
             type === "error"
               ? "&#127827;"
               : type === "success"
               ? "&#127808;"
               : type === "warn"
               ? "&#127819;"
               : "&#128051;"
           }}
           : {{ message }}
         </div>
       </div>
     </transition>
   </template>
   <script>
   export default {
     props: {
       title: {
         type: String,
         default: "",
       },
       message: {
         type: String,
         default: "",
       },
       time: {
         type: Number,
         default: 1000,
       },
       type: {
         type: String,
       },
     },
     data() {
       return {
         isShow: false,
       };
     },
     methods: {
       show() {
         this.isShow = true;
         setTimeout(this.hide, this.time);
       },
       hide() {
         this.isShow = false;
       },
       afterLeave() {
         this.remove();
       },
     },
   };
   </script>
   <style lang="less" scoped>
   @error: rgb(255, 30, 30);
   @warn: rgb(240, 192, 0);
   @success: rgb(0, 144, 74);
   @info: rgb(0, 80, 218);
   
   @errorBg: rgb(255, 208, 208);
   @warnBg: rgb(255, 245, 207);
   @successBg: rgb(210, 255, 233);
   @infoBg: rgb(203, 222, 255);
   
   .notice__root {
     user-select: none;
     padding: 5px 50px 5px 5px;
   }
   
   .noticer {
     padding: 5px 20px;
     margin: 10px 0px;
     // margin-right: 50px;
     border-radius: 8px;
     font-size: 16px;
     width: auto;
     min-width: 280px;
     max-width: 300px;
     word-break: break-all;
     text-align: center;
     box-sizing: border-box;
   }
   .notice-type-error {
     color: @error !important;
     border: 2px solid @error;
     box-shadow: 1px 1px 5px 2px @errorBg;
     background-color: @errorBg;
   
     // border: 1px solid red;
   }
   .notice-type-warn {
     color: @warn !important;
     border: 2px solid @warn;
     background-color: @warnBg;
     box-shadow: 1px 1px 5px 2px @warnBg;
   }
   .notice-type-success {
     color: @success !important;
     border: 2px solid @success;
     background-color: @successBg;
     box-shadow: 1px 1px 5px 2px @successBg;
   }
   .notice-type-info {
     color: @info !important;
     border: 2px solid @info;
     background-color: @infoBg;
     box-shadow: 1px 1px 5px 2px @infoBg;
   }
   </style>
   

3. stay main.js You can execute the script by importing the script in

   import Vue from "vue";
   import App from "./App.vue";
   import "animate.css";
   import "@/components/Noticer/NotificationBanner.js";
   
   
   new Vue({
     render: (h) => h(App),
   }).$mount("#app");
   

4. Examples used in code ：

   if (!this.nickname) {
       this.$notice.error({
           message: " Hero ！ whose names ？",
           time: 3000,
       });
   } else {
       this.showModal = false;
       this.$notice.info({
           message: this.nickname + " coming ！！！",
           time: 3000,
       });
   }
   

Dynamically create the execution logic of components ：
When in use ：

this.$notice.error({
    message: " Hero ！ whose names ？",
    time: 3000,
});

The code above triggers , It actually triggers NotificationBanner.js Medium create function , This function creates one notice Component instance of , And added a remove Method , Then directly trigger the... In the component show Method .

notice In template instance ：

methods: {
    show() {
        this.isShow = true;
        setTimeout(this.hide, this.time);
    },
    hide() {
        this.isShow = false;
    },
    afterLeave() {
        this.remove();
    },
},

show Method execution , Apart from showing notice, Immediately set a delay function to execute hide Method .

hide Method execution , vue Provided transition hook afterleave() Will be triggered after the removal animation is completed . Now , To trigger remove Method , Will be notice Component instance removal .