Vue：window.onresize

1. 添加屬性screenHeight 和 timer。

screenHeight: window.innerHeight

timer: '' //  window.onresize函數頻繁調用時，頁面抖動較大，設定間隔

2. 在mounted 鈎子函數中監聽onresize事件

let that = this

window.onresize = () => {

    if (!that.timer) {

        that.timer = true

        setTimeout(() => {

            that.timer = false

            that.screenHeight = window.innerHeight

        }, 600)

    }

}

3. h5 新單位 vh,vw