前端画面－下拉后滚动

Posted 2020-07-23 舒润

tags:

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前端出现混合模式，一个站点需要手机访问和PC访问，在进行混合模式中，一个分页下拉滚动的功能是需要自己考虑的，这里有两种方法，自己开发和使用插件。为了减少开发复杂难度，插件有：iscroll 和 https://github.com/ximan/dropload，这个都是没有实验过的插件，在进行插件使用的时候，值得注意的点在于，iscroll-probe.js的插件中，有一个参数一定要注意，

//preventDefault: true,

这个参数是将A标签对应的默认事件都去除，使得A标签将会失效，如果你需要将A标签释放出来，那么，这个参数需要修改为false即可，还有一个地方需要注意，如果进行加载的时候，有出现拉下，松手后反弹的情况，那么，将异步加载的方式设置为

async: false,

效果会更好，所以，在前端的时候值得注意点的是这两个，然后附上前端部分js代码，进行使用，

<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=0, minimum-scale=1.0, maximum-scale=1.0">
<meta name="apple-mobile-web-app-capable" content="yes">
<meta name="apple-mobile-web-app-status-bar-style" content="black">
<title>iScroll demo: simple</title>

<script type="text/javascript" src="../../src/iscroll.js"></script>

<script type="text/javascript">

var myScroll,
    pullDownEl, pullDownOffset,
    pullUpEl, pullUpOffset,
    generatedCount = 0;

function pullDownAction () {
    setTimeout(function () {    // <-- Simulate network congestion, remove setTimeout from production!
        var el, li, i;
        el = document.getElementById(\'thelist\');

        for (i=0; i<3; i++) {
            li = document.createElement(\'li\');
            li.innerText = \'Generated row \' + (++generatedCount);
            el.insertBefore(li, el.childNodes[0]);
        }
        
        myScroll.refresh();        // Remember to refresh when contents are loaded (ie: on ajax completion)
    }, 1000);    // <-- Simulate network congestion, remove setTimeout from production!
}

function pullUpAction () {
    setTimeout(function () {    // <-- Simulate network congestion, remove setTimeout from production!
        var el, li, i;
        el = document.getElementById(\'thelist\');

        for (i=0; i<3; i++) {
            li = document.createElement(\'li\');
            li.innerText = \'Generated row \' + (++generatedCount);
            el.appendChild(li, el.childNodes[0]);
        }
        
        myScroll.refresh();        // Remember to refresh when contents are loaded (ie: on ajax completion)
    }, 1000);    // <-- Simulate network congestion, remove setTimeout from production!
}

function loaded() {
    pullDownEl = document.getElementById(\'pullDown\');
    pullDownOffset = pullDownEl.offsetHeight;
    pullUpEl = document.getElementById(\'pullUp\');    
    pullUpOffset = pullUpEl.offsetHeight;
    
    myScroll = new iScroll(\'wrapper\', {
        useTransition: true,
        topOffset: pullDownOffset,
        onRefresh: function () {
            if (pullDownEl.className.match(\'loading\')) {
                pullDownEl.className = \'\';
                pullDownEl.querySelector(\'.pullDownLabel\').innerHTML = \'Pull down to refresh...\';
            } else if (pullUpEl.className.match(\'loading\')) {
                pullUpEl.className = \'\';
                pullUpEl.querySelector(\'.pullUpLabel\').innerHTML = \'Pull up to load more...\';
            }
        },
        onScrollMove: function () {
            if (this.y > 5 && !pullDownEl.className.match(\'flip\')) {
                pullDownEl.className = \'flip\';
                pullDownEl.querySelector(\'.pullDownLabel\').innerHTML = \'Release to refresh...\';
                this.minScrollY = 0;
            } else if (this.y < 5 && pullDownEl.className.match(\'flip\')) {
                pullDownEl.className = \'\';
                pullDownEl.querySelector(\'.pullDownLabel\').innerHTML = \'Pull down to refresh...\';
                this.minScrollY = -pullDownOffset;
            } else if (this.y < (this.maxScrollY - 5) && !pullUpEl.className.match(\'flip\')) {
                pullUpEl.className = \'flip\';
                pullUpEl.querySelector(\'.pullUpLabel\').innerHTML = \'Release to refresh...\';
                this.maxScrollY = this.maxScrollY;
            } else if (this.y > (this.maxScrollY + 5) && pullUpEl.className.match(\'flip\')) {
                pullUpEl.className = \'\';
                pullUpEl.querySelector(\'.pullUpLabel\').innerHTML = \'Pull up to load more...\';
                this.maxScrollY = pullUpOffset;
            }
        },
        onScrollEnd: function () {
            if (pullDownEl.className.match(\'flip\')) {
                pullDownEl.className = \'loading\';
                pullDownEl.querySelector(\'.pullDownLabel\').innerHTML = \'Loading...\';                
                pullDownAction();    // Execute custom function (ajax call?)
            } else if (pullUpEl.className.match(\'flip\')) {
                pullUpEl.className = \'loading\';
                pullUpEl.querySelector(\'.pullUpLabel\').innerHTML = \'Loading...\';                
                pullUpAction();    // Execute custom function (ajax call?)
            }
        }
    });
    
    setTimeout(function () { document.getElementById(\'wrapper\').style.left = \'0\'; }, 800);
}

document.addEventListener(\'touchmove\', function (e) { e.preventDefault(); }, false);

document.addEventListener(\'DOMContentLoaded\', function () { setTimeout(loaded, 200); }, false);
</script>

<style type="text/css" media="all">
body,ul,li {
    padding:0;
    margin:0;
    border:0;
}

body {
    font-size:12px;
    -webkit-user-select:none;
    -webkit-text-size-adjust:none;
    font-family:helvetica;
}

#header {
    position:absolute; z-index:2;
    top:0; left:0;
    width:100%;
    height:45px;
    line-height:45px;
    background-color:#d51875;
    background-image:-webkit-gradient(linear, 0 0, 0 100%, color-stop(0, #fe96c9), color-stop(0.05, #d51875), color-stop(1, #7b0a2e));
    background-image:-moz-linear-gradient(top, #fe96c9, #d51875 5%, #7b0a2e);
    background-image:-o-linear-gradient(top, #fe96c9, #d51875 5%, #7b0a2e);
    padding:0;
    color:#eee;
    font-size:20px;
    text-align:center;
}

#header a {
    color:#f3f3f3;
    text-decoration:none;
    font-weight:bold;
    text-shadow:0 -1px 0 rgba(0,0,0,0.5);
}

#footer {
    position:absolute; z-index:2;
    bottom:0; left:0;
    width:100%;
    height:48px;
    background-color:#222;
    background-image:-webkit-gradient(linear, 0 0, 0 100%, color-stop(0, #999), color-stop(0.02, #666), color-stop(1, #222));
    background-image:-moz-linear-gradient(top, #999, #666 2%, #222);
    background-image:-o-linear-gradient(top, #999, #666 2%, #222);
    padding:0;
    border-top:1px solid #444;
}

#wrapper {
    position:absolute; z-index:1;
    top:45px; bottom:48px; left:-9999px;
    width:100%;
    background:#aaa;
    overflow:auto;
}

#scroller {
    position:absolute; z-index:1;
/*    -webkit-touch-callout:none;*/
    -webkit-tap-highlight-color:rgba(0,0,0,0);
    width:100%;
    padding:0;
}

#scroller ul {
    list-style:none;
    padding:0;
    margin:0;
    width:100%;
    text-align:left;
}

#scroller li {
    padding:0 10px;
    height:40px;
    line-height:40px;
    border-bottom:1px solid #ccc;
    border-top:1px solid #fff;
    background-color:#fafafa;
    font-size:14px;
}

#myFrame {
    position:absolute;
    top:0; left:0;
}



/**
 *
 * Pull down styles
 *
 */
#pullDown, #pullUp {
    background:#fff;
    height:40px;
    line-height:40px;
    padding:5px 10px;
    border-bottom:1px solid #ccc;
    font-weight:bold;
    font-size:14px;
    color:#888;
}
#pullDown .pullDownIcon, #pullUp .pullUpIcon  {
    display:block; float:left;
    width:40px; height:40px;
    background:url(pull-icon@2x.png) 0 0 no-repeat;
    -webkit-background-size:40px 80px; background-size:40px 80px;
    -webkit-transition-property:-webkit-transform;
    -webkit-transition-duration:250ms;    
}
#pullDown .pullDownIcon {
    -webkit-transform:rotate(0deg) translateZ(0);
}
#pullUp .pullUpIcon  {
    -webkit-transform:rotate(-180deg) translateZ(0);
}

#pullDown.flip .pullDownIcon {
    -webkit-transform:rotate(-180deg) translateZ(0);
}

#pullUp.flip .pullUpIcon {
    -webkit-transform:rotate(0deg) translateZ(0);
}

#pullDown.loading .pullDownIcon, #pullUp.loading .pullUpIcon {
    background-position:0 100%;
    -webkit-transform:rotate(0deg) translateZ(0);
    -webkit-transition-duration:0ms;

    -webkit-animation-name:loading;
    -webkit-animation-duration:2s;
    -webkit-animation-iteration-count:infinite;
    -webkit-animation-timing-function:linear;
}

@-webkit-keyframes loading {
    from { -webkit-transform:rotate(0deg) translateZ(0); }
    to { -webkit-transform:rotate(360deg) translateZ(0); }
}

</style>
</head>
<body>

<div id="header"><a href="http://cubiq.org/iscroll">iScroll</a></div>
<div id="wrapper">
    <div id="scroller">
        <div id="pullDown">
            <span class="pullDownIcon"></span><span class="pullDownLabel">Pull down to refresh...</span>
        </div>

        <ul id="thelist">
            <li>Pretty row 1</li>
            <li>Pretty row 2</li>
            <li>Pretty row 3</li>
            <li>Pretty row 4</li>
            <li>Pretty row 5</li>
            <li>Pretty row 6</li>
            <li>Pretty row 7</li>
            <li>Pretty row 8</li>
            <li>Pretty row 9</li>
            <li>Pretty row 10</li>
            <li>Pretty row 11</li>
            <li>Pretty row 12</li>
            <li>Pretty row 13</li>
            <li>Pretty row 14</li>
            <li>Pretty row 15</li>
            <li>Pretty row 16</li>
            <li>Pretty row 17</li>
            <li>Pretty row 18</li>
            <li>Pretty row 19</li>
            <li>Pretty row 20</li>
            <li>Pretty row 21</li>
            <li>Pretty row 22</li>
            <li>Pretty row 23</li>
            <li>Pretty row 24</li>
            <li>Pretty row 25</li>
            <li>Pretty row 26</li>
            <li>Pretty row 27</li>
            <li>Pretty row 28</li>
            <li>Pretty row 29</li>
            <li>Pretty row 30</li>
            <li>Pretty row 31</li>
            <li>Pretty row 32</li>
            <li>Pretty row 33</li>
            <li>Pretty row 34</li>
            <li>Pretty row 35</li>
            <li>Pretty row 36</li>
            <li>Pretty row 37</li>
            <li>Pretty row 38</li>
            <li>Pretty row 39</li>
            <li>Pretty row 40</li>
        </ul>
        <div id="pullUp">
            <span class="pullUpIcon"></span><span class="pullUpLabel">Pull up to refresh...</span>
        </div>
    </div>
</div>
<div id="footer"></div>

</body>
</html>

View Code

这个是官网的demo：地址view-source:http://cubiq.org/dropbox/iscroll4/examples/pull-to-refresh/

主要的js代码片段

var myScroll,
    pullDownEl, pullDownOffset,
    pullUpEl, pullUpOffset,
    generatedCount = 0;

function pullDownAction () {
    setTimeout(function () {    // <-- Simulate network congestion, remove setTimeout from production!
        var el, li, i;
        el = document.getElementById(\'thelist\');

        for (i=0; i<3; i++) {
            li = document.createElement(\'li\');
            li.innerText = \'Generated row \' + (++generatedCount);
            el.insertBefore(li, el.childNodes[0]);
        }
        
        myScroll.refresh();        // Remember to refresh when contents are loaded (ie: on ajax completion)
    }, 1000);    // <-- Simulate network congestion, remove setTimeout from production!
}

function pullUpAction () {
    setTimeout(function () {    // <-- Simulate network congestion, remove setTimeout from production!
        var el, li, i;
        el = document.getElementById(\'thelist\');

        for (i=0; i<3; i++) {
            li = document.createElement(\'li\');
            li.innerText = \'Generated row \' + (++generatedCount);
            el.appendChild(li, el.childNodes[0]);
        }
        
        myScroll.refresh();        // Remember to refresh when contents are loaded (ie: on ajax completion)
    }, 1000);    // <-- Simulate network congestion, remove setTimeout from production!
}

function loaded() {
    pullDownEl = document.getElementById(\'pullDown\');
    pullDownOffset = pullDownEl.offsetHeight;
    pullUpEl = document.getElementById(\'pullUp\');    
    pullUpOffset = pullUpEl.offsetHeight;
    
    myScroll = new iScroll(\'wrapper\', {
        useTransition: true,
        topOffset: pullDownOffset,
        onRefresh: function () {
            if (pullDownEl.className.match(\'loading\')) {
                pullDownEl.className = \'\';
                pullDownEl.querySelector(\'.pullDownLabel\').innerHTML = \'Pull down to refresh...\';
            } else if (pullUpEl.className.match(\'loading\')) {
                pullUpEl.className = \'\';
                pullUpEl.querySelector(\'.pullUpLabel\').innerHTML = \'Pull up to load more...\';
            }
        },
        onScrollMove: function () {
            if (this.y > 5 && !pullDownEl.className.match(\'flip\')) {
                pullDownEl.className = \'flip\';
                pullDownEl.querySelector(\'.pullDownLabel\').innerHTML = \'Release to refresh...\';
                this.minScrollY = 0;
            } else if (this.y < 5 && pullDownEl.className.match(\'flip\')) {
                pullDownEl.className = \'\';
                pullDownEl.querySelector(\'.pullDownLabel\').innerHTML = \'Pull down to refresh...\';
                this.minScrollY = -pullDownOffset;
            } else if (this.y < (this.maxScrollY - 5) && !pullUpEl.className.match(\'flip\')) {
                pullUpEl.className = \'flip\';
                pullUpEl.querySelector(\'.pullUpLabel\').innerHTML = \'Release to refresh...\';
                this.maxScrollY = this.maxScrollY;
            } else if (this.y > (this.maxScrollY + 5) && pullUpEl.className.match(\'flip\')) {
                pullUpEl.className = \'\';
                pullUpEl.querySelector(\'.pullUpLabel\').innerHTML = \'Pull up to load more...\';
                this.maxScrollY = pullUpOffset;
            }
        },
        onScrollEnd: function () {
            if (pullDownEl.className.match(\'flip\')) {
                pullDownEl.className = \'loading\';
                pullDownEl.querySelector(\'.pullDownLabel\').innerHTML = \'Loading...\';                
                pullDownAction();    // Execute custom function (ajax call?)
            } else if (pullUpEl.className.match(\'flip\')) {
                pullUpEl.className = \'loading\';
                pullUpEl.querySelector(\'.pullUpLabel\').innerHTML = \'Loading...\';                
                pullUpAction();    // Execute custom function (ajax call?)
            }
        }
    });
    
    setTimeout(function () { document.getElementById(\'wrapper\').style.left = \'0\'; }, 800);
}

document.addEventListener(\'touchmove\', function (e) { e.preventDefault(); }, false);

document.addEventListener(\'DOMContentLoaded\', function () { setTimeout(loaded, 200); }, false);

View Code

使用的时候注意

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