技巧

异步代码写在最后
比如一个函数里有异步，那么就把异步写在这个函数的最后

updateChildren() {
    this.$children.map(vm => {
        if (this.lastSelectedIndex > this.selectedIndex) {
            vm.reverse = true
        }

        if (this.lastSelectedIndex < this.selectedIndex) {
            vm.reverse = false
        }
        if(this.timer && !this.one){
            if (this.lastSelectedIndex === this.names.length - 1 && this.selectedIndex === 0) {
                vm.reverse = false
            }
            if (this.lastSelectedIndex === 0 && this.selectedIndex === this.names.length - 1) {
                vm.reverse = true
            }
        }
        this.$nextTick(() => {
            vm.selected = this.selected
        })
    })