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JavaScript implements the 'Creative Clock' project

一个新手

May 30, 2018 pm 02:36 PM

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"Clock Display Project" description document (Document has the corresponding code at the end)

1. Final effect display:

2. Project Highlights

1. The code structure is clear and clear

2. Can dynamically display the current time and date in real time

3. The interface is simple, beautiful and generous

4. Improve browser compatibility

3. Summary of knowledge points:

jQuery, native javascript, css3, h5

4. Explanation of important and difficult points

1. Obtaining the rotation angle of each pointer

First of all, we must clarify the following concepts:

The clock hand rotates 360 degrees in a circle

Hour hand:

There are 12 hours in total on the dial. Every hour, it rotates 30 degrees;

Minute hand:

There are 60 hours in total on the dial Grid, every minute the minute hand moves through a small grid, it rotates 6 degrees;

Second hand:

There are a total of 60 small grids on the dial , every minute the second hand moves, it passes through a small grid and rotates 6 degrees;

(1) Obtaining the current time

Give an example Example (taking the hour hand rotation angle calculation as an example): For example, the current time is 9:28;

The hour hand should be between 9 and 10, and only the hour can be obtained through the method, so both To obtain the current hour, you must also obtain the current minute, so that you can better determine the rotation angle of the hour hand, which is as follows:

(2) Rotation Obtaining the angle

Since the hour hand rotates 30 degrees after every hour, the rotation angle of the hour hand is obtained as follows:

Similarly, the angle of the minute hand and the second hand The rotation angle is as follows:

Minute hand:

Second hand:

In order to make the clock more accurate , here is accurate to milliseconds;

(3) Execution frequency, that is, second hand rotation frequency control

Adjust the execution time interval of the function to change the second hand rotation frequency .

5. Project optimization areas

1. The page is too concise and needs further optimization and improvement;

2. There is no time to draw minutes and seconds on the clock when drawing;

6. Codes for each part of the project

1.HTML code

<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <title>jQuery指针时钟（附带日期）</title>
    <!--引入外部css样式-->
    <link rel="stylesheet" href="css/demo.css" type="text/css" media="screen" />
</head>
<body>
    <!--引入jQuery库文件-->
    <script src="js/jquery-1.6.2.min.js"></script>
    <!--引入外部js文件-->
    <script src="js/script.js"></script>
    <p style="text-align:center;clear:both">
    </p>
</body>
</html>

2.css code

*
{
    margin:0;
    padding:0;
}
body
{
    background:#f9f9f9;
    color:#000;
    font:15px Calibri, Arial, sans-serif;
    text-shadow:1px 2px 1px #FFFFFF;
}
a,
a:visited
{
    text-decoration:none;
    outline:none;
    color:#fff;
}
a:hover
{
    text-decoration:underline;
    color:#ddd;
}
     /*the footer  （尾部）*/
footer
{
    background:#444 url("../images/bg-footer.png") repeat;
    position:fixed;
    width:100%;
    height:70px;
    bottom:0;
    left:0;
    color:#fff;
    text-shadow:2px 2px #000;
    /*提高浏览器的兼容性*/
    -moz-box-shadow:5px 1px 10px #000;
    -webkit-box-shadow:5px 1px 10px #000;
    box-shadow:5px 1px 10px #000;
}
footer h1
{
    font:25px/26px Acens;
    font-weight:normal;
    left:50%;
    margin:0px 0 0 150px;
    padding:25px 0;
    position:relative;
    width:400px;
}
footer a.orig,
a.orig:visited
{
    background:url("../images/demo2.png") no-repeat right top;
    border:none;
    text-decoration:none;
    color:#FCFCFC;
    font-size:14px;
    height:70px;
    left:50%;
    line-height:50px;
    margin:12px 0 0 -400px;
    position:absolute;
    top:0;
    width:250px;
}
     /*styling for the clock（时钟样式）*/
#clock
{
    position: relative;
    width: 600px;
    height: 600px;
    list-style: none;
    margin: 20px auto;
    background: url(&#39;../images/clock.png&#39;) no-repeat center;
    
}
#seconds,
#minutes,
#hours
{
    position: absolute;
    width: 30px;
    height: 580px;
    left: 270px;
}
#date
{
    position: absolute;
    top: 365px;
    color: #666;
    right: 140px;
    font-weight: bold;
    letter-spacing: 3px;
    font-family: "微软雅黑";
    font-size: 30px;
    line-height: 36px;
}
#hours
{
    background: url(&#39;../images/hands.png&#39;) no-repeat left;
    z-index: 1000;
}
#minutes
{
    background: url(&#39;../images/hands.png&#39;) no-repeat center;
    width:25px;
    z-index: 2000;
}

#seconds
{
    background: url(&#39;../images/hands.png&#39;) no-repeat right;
    z-index: 3000;
}

View Code

3.js code

(1) You need to download a js reference package (you will know it by Baidu or Google)

(2) js code

$(document).ready(function () {
    //动态插入HTML代码，标记时钟    
    var clock = [
        &#39;<ul id="clock">&#39;,
        &#39;<li id="date"></li>&#39;,
        &#39;<li id="seconds"></li>&#39;,
        &#39;<li id="hours"></li>&#39;,
        &#39;<li id="minutes"></li>&#39;,
        &#39;</ul>&#39;].join(&#39;&#39;);
    // 逐渐显示时钟，并把它附加到主页面中    
    $(clock).fadeIn().appendTo(&#39;body&#39;);
    //每一秒钟更新时钟视图的自动执行函数
    //也可以使用此方法： setInterval (function Clock (){})();
    (function Clock() {
        //得到日期和时间
        var date = new Date().getDate(),        //得到当前日期
           hours = new Date().getHours(),       //得到当前小时
         minutes = new Date().getMinutes();        //得到当前分钟
         seconds = new Date().getSeconds(),     //得到当前秒
              ms = new Date().getMilliseconds();//得到当前毫秒
        //将当前日期显示在时钟上
        $("#date").html(date);
        //获取当前秒数，确定秒针位置
        var srotate = seconds + ms / 1000;
        $("#seconds").css({
            //确定旋转角度
            &#39;transform&#39;: &#39;rotate(&#39; + srotate * 6 + &#39;deg)&#39;,       
        });
        //获取当前分钟数，得到分针位置
        var mrotate = minutes + srotate / 60; 
        $("#minutes").css({
            &#39;transform&#39;: &#39;rotate(&#39; + mrotate * 6 + &#39;deg)&#39;,
            //提高浏览器的兼容性
            &#39;-moz-transform&#39;: &#39;rotate(&#39; + mrotate * 6 + &#39;deg)&#39;,
            &#39;-webkit-transform&#39;: &#39;rotate(&#39; + mrotate * 6 + &#39;deg)&#39;
        });
        //获取当前小时，得到时针位置
        var hrotate = hours % 12 + (minutes / 60);
        $("#hours").css({
            &#39;transform&#39;: &#39;rotate(&#39; + hrotate * 30 + &#39;deg)&#39;,
            //提高浏览器的兼容性
            &#39;-moz-transform&#39;: &#39;rotate(&#39; + hrotate * 30 + &#39;deg)&#39;,
            &#39;-webkit-transform&#39;: &#39;rotate(&#39; + hrotate * 30 + &#39;deg)&#39;
        });
        //每一秒后执行一次时钟函数
        setTimeout(Clock, 1000);
    })();
});

4. Some necessary picture materials (c will not be listed or displayed one by one here)

Notes:

1.Transform property

2.rotate() method

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