滚动时如何在菜单栏下隐藏日历答案

【问题标题】：How to hide calendar under the menu bar when scrolling滚动时如何在菜单栏下隐藏日历
【发布时间】：2020-07-08 14:42:48
【问题描述】：

<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1">
<style>
body {
  margin: 0;
  background-color: #f1f1f1;
  font-family: Arial, Helvetica, sans-serif;
}

#navbar {
  background-color: #333;
  position: fixed;
  top: 0;
  width: 100%;
  display: block;
  transition: top 0.3s;
}

#navbar a {
  float: left;
  display: block;
  color: #f2f2f2;
  text-align: center;
  padding: 15px;
  text-decoration: none;
  font-size: 17px;
}

#navbar a:hover {
  background-color: #ddd;
  color: black;
}
</style>
</head>
<body>
<!-- jQuery -->
<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js" integrity="sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo" crossorigin="anonymous"></script>

<br />
<input id="datetimepicker" type="text" >

<div id="navbar">
  <a href="#home">Home</a>
  <a href="#news">News</a>
  <a href="#contact">Contact</a>
</div>

<div style="padding:15px 15px 2500px;font-size:30px;margin-top:30px;">
  <p><b>This example demonstrates how to hide a navbar when the user starts to scroll the page.</b></p>
  
  
  <p>Scroll down this frame to see the effect!</p>
  <p>Scroll up to show the navbar.</p>
  <p>Lorem ipsum dolor dummy text sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.</p>
  <p>Lorem ipsum dolor dummy text sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.</p>
</div>

<script>
$(function(){
  $('#datetimepicker').datetimepicker({
    inline:true,
    });
})
var prevScrollpos = window.pageYOffset;
window.onscroll = function() {
var currentScrollPos = window.pageYOffset;
  if (prevScrollpos > currentScrollPos) {
    document.getElementById("navbar").style.top = "0";
  } else {
    document.getElementById("navbar").style.top = "-50px";
  }
  prevScrollpos = currentScrollPos;
}
</script>


</body>
<!-- XDSoft DateTimePicker -->
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/jquery-datetimepicker/2.5.20/jquery.datetimepicker.min.css" integrity="sha256-DOS9W6NR+NFe1fUhEE0PGKY/fubbUCnOfTje2JMDw3Y=" crossorigin="anonymous" />
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery-datetimepicker/2.5.20/jquery.datetimepicker.full.min.js" integrity="sha256-FEqEelWI3WouFOo2VWP/uJfs1y8KJ++FLh2Lbqc8SJk=" crossorigin="anonymous"></script>
</html>

我在 Django 中使用以下日历： https://xdsoft.net/jqplugins/datetimepicker/
问题是当向下滚动页面时，月历和年历组件越过我的菜单栏。有办法解决这个问题吗？也许从日历或我的 HTML/Javascript 中覆盖一些 css？
我在 w3school 的 HTML 示例中重现了我的场景。查看代码被截断。

【问题讨论】：

标签： javascript html css django

【解决方案1】：

不需要为内联日历设置如此高的 z-index 值，因为不像默认日历那样显示在日期字段上。
而不是z-index: 9999 使用z-index: 101 就像下拉菜单一样月和年使用。解决方案是覆盖日历的 css：
```
 <script>
 .xdsoft_datetimepicker .xdsoft_label {
     z-index: 101 !important;
 }
 </script>
```

【讨论】：