我有下面的样本html,有一个DIV有100%的宽度。它包含了一些元素。在执行窗口调整大小时,内部元素可能会被重新定位,div的尺寸可能会改变。我在问是否有可能挂钩div的维度变化事件?以及如何做到这一点?我目前绑定回调函数到目标DIV上的jQuery调整大小事件,但是,没有输出控制台日志,如下所示:

<html>
<head>
    <script type="text/javascript" language="javascript" src="http://code.jquery.com/jquery-1.6.1.min.js"></script>
    <script type="text/javascript" language="javascript">
            $('#test_div').bind('resize', function(){
                console.log('resized');
            });
    </script>
</head>
<body>
    <div id="test_div" style="width: 100%; min-height: 30px; border: 1px dashed pink;">
        <input type="button" value="button 1" />
        <input type="button" value="button 2" />
        <input type="button" value="button 3" />
    </div>
</body>
</html>

当前回答

这几乎是顶部答案的精确副本,但不是链接,它只是重要的代码的一部分,翻译成IMO更易读,更容易理解。其他一些小的改变包括使用cloneNode(),和不把html放入js字符串。很小的东西,但是你可以复制粘贴它就可以了。

它的工作方式是让两个看不见的div填充你正在观看的元素,然后在每个div中设置一个触发器,并设置一个滚动位置,如果大小发生变化,将导致触发滚动变化。

所有真正的荣誉都属于Marc J,但如果你只是在寻找相关的代码,这里是:

    window.El = {}

    El.resizeSensorNode = undefined;
    El.initResizeNode = function() {
        var fillParent = "display: block; position: absolute; left: 0; top: 0; right: 0; bottom: 0; overflow: hidden; z-index: -1; visibility: hidden;";
        var triggerStyle = "position: absolute; left: 0; top: 0; transition: 0s;";

        var resizeSensor = El.resizeSensorNode = document.createElement("resizeSensor");
        resizeSensor.style = fillParent;

        var expandSensor = document.createElement("div");
        expandSensor.style = fillParent;
        resizeSensor.appendChild(expandSensor);

        var trigger = document.createElement("div");
        trigger.style = triggerStyle;
        expandSensor.appendChild(trigger);

        var shrinkSensor = expandSensor.cloneNode(true);
        shrinkSensor.firstChild.style = triggerStyle + " width: 200%; height: 200%";
        resizeSensor.appendChild(shrinkSensor);
    }


    El.onSizeChange = function(domNode, fn) {
        if (!domNode) return;
        if (domNode.resizeListeners) {
            domNode.resizeListeners.push(fn);
            return;
        }

        domNode.resizeListeners = [];
        domNode.resizeListeners.push(fn);

        if(El.resizeSensorNode == undefined)
            El.initResizeNode();

        domNode.resizeSensor = El.resizeSensorNode.cloneNode(true);
        domNode.appendChild(domNode.resizeSensor);

        var expand = domNode.resizeSensor.firstChild;
        var expandTrigger = expand.firstChild;
        var shrink = domNode.resizeSensor.childNodes[1];

        var reset = function() {
            expandTrigger.style.width = '100000px';
            expandTrigger.style.height = '100000px';

            expand.scrollLeft = 100000;
            expand.scrollTop = 100000;

            shrink.scrollLeft = 100000;
            shrink.scrollTop = 100000;
        };

        reset();

        var hasChanged, frameRequest, newWidth, newHeight;
        var lastWidth = domNode.offsetWidth;
        var lastHeight = domNode.offsetHeight;


        var onResized = function() {
            frameRequest = undefined;

            if (!hasChanged) return;

            lastWidth = newWidth;
            lastHeight = newHeight;

            var listeners = domNode.resizeListeners;
            for(var i = 0; listeners && i < listeners.length; i++) 
                listeners[i]();
        };

        var onScroll = function() {
            newWidth = domNode.offsetWidth;
            newHeight = domNode.offsetHeight;
            hasChanged = newWidth != lastWidth || newHeight != lastHeight;

            if (hasChanged && !frameRequest) {
                frameRequest = requestAnimationFrame(onResized);
            }

            reset();
        };


        expand.addEventListener("scroll", onScroll);
        shrink.addEventListener("scroll", onScroll);
    }

其他回答

使用Clay.js (https://github.com/zzarcon/clay),检测元素大小的变化非常简单:

var el = new Clay('.element');

el.on('resize', function(size) {
    console.log(size.height, size.width);
});

使用disconnect删除事件监听器:

import { Controller } from "@hotwired/stimulus"

export default class extends Controller {
  static targets = ["input", "context", "output"]

  connect() {
    this.inputObserver = new ResizeObserver(() => { this.resizeInput() })
    this.inputObserver.observe(this.inputTarget)
  }

  disconnect() {
    this.inputObserver.disconnect(this.inputTarget)
  }

  resizeInput() {
    const height = this.inputTarget.offsetHeight

    this.contextTarget.style.height = `${height}px`
    this.outputTarget.style.height = `${height}px`
  }
}

您可以尝试以下代码片段中的代码,它使用纯javascript满足您的需求。(如果您想测试div,则运行代码片段并单击整页链接以触发div调整大小的警报。)

基于这是一个100毫秒的setInterval的事实,我敢说我的PC没有发现它太多的CPU饥饿。(0.1%的CPU被用作测试时Chrome中所有打开的选项卡的总和。)但这只是一个div,如果你想为大量的元素这样做,那么是的,它可能是非常CPU饥饿。 无论如何,您总是可以使用单击事件来停止div-resize嗅探。

var width = 0; var interval = setInterval(function(){ if(width <= 0){ width = document.getElementById("test_div").clientWidth; } if(document.getElementById("test_div").clientWidth!==width) { alert('resized div'); width = document.getElementById("test_div").clientWidth; } }, 100); <div id="test_div" style="width: 100%; min-height: 30px; border: 1px dashed pink;"> <input type="button" value="button 1" /> <input type="button" value="button 2" /> <input type="button" value="button 3" /> </div>

你也可以检查一下小提琴

更新

var width = 0; function myInterval() { var interval = setInterval(function(){ if(width <= 0){ width = document.getElementById("test_div").clientWidth; } if(document.getElementById("test_div").clientWidth!==width) { alert('resized'); width = document.getElementById("test_div").clientWidth; } }, 100); return interval; } var interval = myInterval(); document.getElementById("clickMe").addEventListener( "click" , function() { if(typeof interval!=="undefined") { clearInterval(interval); alert("stopped div-resize sniffing"); } }); document.getElementById("clickMeToo").addEventListener( "click" , function() { myInterval(); alert("started div-resize sniffing"); }); <div id="test_div" style="width: 100%; min-height: 30px; border: 1px dashed pink;"> <input type="button" value="button 1" id="clickMe" /> <input type="button" value="button 2" id="clickMeToo" /> <input type="button" value="button 3" /> </div>

更新的小提琴

通过@gman扩展这个答案,这里有一个允许每个元素多次回调的函数,将宽度和高度分解为一个准事件对象。请参阅关于堆栈溢出的嵌入式演示(您可能需要彻底调整主浏览器的大小以触发它)

function elementResizeWatcher(element, callback) { var resolve=function(element) { return (typeof element==='string' ? document[ ['.','#'].indexOf(element.charAt(0)) < 0 ? "getElementById" : "querySelector" ] (element) : element); }, observer, watched = [], checkForElementChanges = function (data) { var w=data.el.offsetWidth,h=data.el.offsetHeight; if ( data.offsetWidth !== w || data.offsetHeight !== h ) { data.offsetWidth = w; data.offsetHeight = h; data.cb({ target : data.el, width : w, height : h }); } }, checkForChanges=function(){ watched.forEach(checkForElementChanges); }, started=false, self = { start: function () { if (!started) { // Listen to the window resize event window.addEventListener("resize", checkForChanges); // Listen to the element being checked for width and height changes observer = new MutationObserver(checkForChanges); observer.observe(document.body, { attributes: true, childList: true, characterData: true, subtree: true }); started=true; } }, stop : function ( ) { if (started) { window.removeEventListener('resize', checkForChanges); observer.disconnect(); started = false; } }, addListener : function (element,callback) { if (typeof callback!=='function') return; var el = resolve(element); if (typeof el==='object') { watched.push({ el : el, offsetWidth : el.offsetWidth, offsetHeight : el.offsetHeight, cb : callback }); } }, removeListener : function (element,callback) { var el = resolve(element); watched = watched.filter(function(data){ return !((data.el===el) && (data.cb===callback)); }); } }; self.addListener(element,callback); self.start(); return self; } var watcher = elementResizeWatcher("#resize_me_on_stack_overflow", function(e){ e.target.innerHTML="i am "+e.width+"px&nbsp;x&nbsp;"+e.height+"px"; }); watcher.addListener(".resize_metoo",function(e) { e.target.innerHTML="and i am "+e.width+"px&nbsp;x&nbsp;"+e.height+"px"; }); var mainsize_info = document.getElementById("mainsize"); watcher.addListener(document.body,function(e) { mainsize_info.innerHTML=e.width+"px&nbsp;x&nbsp;"+e.height+"px"; }); #resize_me_on_stack_overflow{ background-color:lime; } .resize_metoo { background-color:yellow; font-size:36pt; width:50%; } <p> resize the main browser window! <span id="mainsize"><span> </p> <p id="resize_me_on_stack_overflow"> hey, resize me. </p> <p class="resize_metoo"> resize me too. </p>

只有窗口对象生成“调整大小”事件。我所知道的唯一方法是运行一个间隔计时器,定期检查大小。