vue app 切换动画

实现问题

1.如何判断切换路由时是前进还是后退
2.每次切换时向左向右切换动画如何实现

实现原理

1.我们需要给各个页面定义层级,在切换路由时判断用户是进入哪一层页面,如果用户进入更高层级那么做前进动画,如果用户退到低层级那么做后退动画.

import Vue from 'vue'
import VueRouter from 'vue-router'
import Home from '../views/home/Home.vue'
Vue.use(VueRouter)

let routes = [
  {
    path: '/',
    redirect: '/home'
  },
  {
    path: '/home',
    name: 'home',
    component: Home,
    meta: {
      showMenu: true,
      index:0 //meta对象的index用来定义当前路由的层级,由小到大,由低到高
    },
  },
  {
    path: '/login',
    name: 'login',
    component: () => import("@/views/login/login"),
    meta: {
      showMenu: false,
    },
  },
  {
    path: '/register',
    name: 'register',
    component: () => import("@/views/login/register"),
    meta: {
      showMenu: false,
    },
  },
  {
    path: '/retrievePassword',
    name: 'retrievePassword',
    component: () => import("../views/mine/retrievePassword.vue")
    meta: {
        showMenu: false,
    },
  }
]

2.监控路由跳转,判断切换页面之间的层级关系,并以此来判断路由前进或者后退App.vue.

<template>
  <div id="app">
    <footer-menu v-if="showMenu" />
      <transition :mode="mode" :name="transitionName">
        <router-view class="center"></router-view>
      </transition>
  </div>
</template>
  
<script>
export default{
  data() {
    return {
      mode: '',
      transitionName: 'slide-left', //默认动画
    };
  },
 watch: {
    $route(to, from) {
      //页面切换动画
      console.log(to);
      let toName = to.name;
      const toIndex = to.meta.index;
      const fromIndex = from.meta.index;
      if (toIndex == undefined) {
        this.mode = 'out-in';
        this.transitionName = '';
      } else {
        this.mode = '';
        this.transitionName = toIndex < fromIndex ? 'slide-right' : 'slide-left';
      }
    },
  },

}
</script>

3.编写slide-left 和 slide-right 类的动画

// -----------
/*app.vue  的style*/
.slide-right-enter-active,
.slide-right-leave-active,
.slide-left-enter-active,
.slide-left-leave-active {
  will-change: transform;
  transition: all 500ms;
  position: absolute;
}
 
.slide-right-enter {
  opacity: 0;
  transform: translate3d(-100%, 0, 0);
}
 
.slide-right-leave-active {
  opacity: 0;
  transform: translate3d(100%, 0, 0);
}
 
.slide-left-enter {
  opacity: 0;
  transform: translate3d(100%, 0, 0);
}
 
.slide-left-leave-active {
  opacity: 0;
  transform: translate3d(-100%, 0, 0);
}