jquery - 如何完成一次为一个元素添加类(WayPoints)

Question

我有一个很好的 Waypoint.js 滚动列表，当您向下滚动并从目标(窗口)点击一定百分比时，它会更改字体样式并向列表项添加一个箭头。

现在，它在向下的过程中为每个元素添加箭头，并在向上的过程中从每个元素中移除箭头。

我想知道的是，是否有一种方法可以以某种方式说“一次一个”，这将允许元素更改，但一次只能更改一个(即:添加一个箭头(字体很棒)，一次更改一种字体)。

基本上，“不要一次将这个类添加到多个，只有在向下滚动时将它从前面的一个中删除时才添加它(我希望这是有道理的!)

我尝试将其更改为 toggleClass 并从 .siblings() 中删除类，这有点奏效，但因为这些是多个列表，所以它不起作用。每个 ul 中的最后一项保留箭头(我将在下面展示一个示例)。

在这个网站上，您可以看到它以正确的样式和箭头显示:如果您向下滚动此页面到我们的流程部分，您将看到我正在做的事情:slight_smile:

https://stable.stable-demos.com/what-we-do/

另请注意:我知道我可以使用 siblings() 来完成这项工作，除了这些列表必须分解为不同的 ul，因为我们需要它们正确地堆叠在一起以便移动。

感谢您的帮助!

jQuery(function($){

// WHAT WE DO - ACTIVATE LIST AS SCROLL BY CHANGE FONT
	var continuousElements = document.getElementsByClassName("waypoint")
		for (var i = 0; i < continuousElements.length; i++) {
			new Waypoint({
			element: continuousElements[i],
			handler: function(direction) {

					if (direction === "down") {

						console.log(this.element.innerHTML + "down");
						$(this.element).addClass("gray active");
						$(this.element).removeClass("black");

					} else if (direction === "up") { 

						console.log(this.element.innerHTML + "up");
						$(this.element).addClass("black");
						$(this.element).removeClass("gray active");

					}
				}, offset: "50%"
			});

		}

}); // End jQuery

/* What we do Highlight Text */
.black {
	color: black!important;
}
.gray {
	color: black!important;
}
.gray.active:before {
  font-family: "Font Awesome 5 Free";
	content: "\f061";
	padding-right: 10px;
}
.c-logo img {
	width: 80%;
}

.list-wrap div {
	text-transform: uppercase;
	padding: 8px 0;
	text-align: center;
	color: black;
	font-family: 'space_grotesksemibold';
}
.list-wrap div.active,
.list-wrap div:hover {
	color: black;
	font-family: 'gt_sectra_fineblack_italic';
	cursor: pointer;
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/waypoints/4.0.1/jquery.waypoints.min.js"></script>
<div style="min-height: 2000px;">
    <div id="listWrap" class="list-wrap">
    	<div class="continuous-true waypoint">We Think.</div>
    	<div class="continuous-true waypoint">We Research.</div>
    	<div class="continuous-true waypoint">We Involve.</div>
    </div>
    <div id="listWrap" class="list-wrap">
    	<div class="continuous-true waypoint">We Stragegize.</div>
    	<div class="continuous-true waypoint">We Plan.</div>
    	<div class="continuous-true waypoint">We Analyze.</div>
    </div> 
    <div id="listWrap" class="list-wrap">
    	<div class="continuous-true waypoint">We Ideate.</div>
    	<div class="continuous-true waypoint">We Design.</div>
    	<div class="continuous-true waypoint">We Create.</div>
    </div>
    <div id="listWrap" class="list-wrap">
    	<div class="continuous-true waypoint">We Test.</div>
    	<div class="continuous-true waypoint">We Adapt.</div>
    	<div class="continuous-true waypoint">We Execute.</div>
    </div>
    <div id="listWrap" class="list-wrap">
    	<div class="continuous-true waypoint">We Report.</div>
    	<div class="continuous-true waypoint">We Learn.</div>
    	<div class="continuous-true waypoint">We Improve.</div>
    </div>
</div>

与 sibling ():

jQuery(function($){

    // WHAT WE DO - ACTIVATE LIST AS SCROLL BY CHANGE FONT
    	var continuousElements = document.getElementsByClassName("waypoint")
    		for (var i = 0; i < continuousElements.length; i++) {
    			new Waypoint({
    			element: continuousElements[i],
    			handler: function(direction) {

    					if (direction === "down") {

    						console.log(this.element.innerHTML + "down");
    						$(this.element).addClass("gray active").siblings().removeClass('active');;
    						$(this.element).removeClass("black");

    					} else if (direction === "up") { 

    						console.log(this.element.innerHTML + "up");
    						$(this.element).addClass("black");
    						$(this.element).removeClass("gray active");

    					}
    				}, offset: "50%"
    			});

    		}

    }); // End jQuery

 /* What we do Highlight Text */

    .black {
    	color: black!important;
    }
    .gray {
    	color: black!important;
    }
    .gray.active:before {
      font-family: "Font Awesome 5 Free";
    	content: "\f061";
    	padding-right: 10px;
    }
    .c-logo img {
    	width: 80%;
    }

    .list-wrap div {
    	text-transform: uppercase;
    	padding: 8px 0;
    	text-align: center;
    	color: black;
    	font-family: 'space_grotesksemibold';
    }
    .list-wrap div.active,
    .list-wrap div:hover {
    	color: black;
    	font-family: 'gt_sectra_fineblack_italic';
    	cursor: pointer;
    }

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/waypoints/4.0.1/jquery.waypoints.min.js"></script>
<div style="min-height: 2000px;">
    <div id="listWrap" class="list-wrap">
    	<div class="continuous-true waypoint">We Think.</div>
    	<div class="continuous-true waypoint">We Research.</div>
    	<div class="continuous-true waypoint">We Involve.</div>
    </div>
    <div id="listWrap" class="list-wrap">
    	<div class="continuous-true waypoint">We Stragegize.</div>
    	<div class="continuous-true waypoint">We Plan.</div>
    	<div class="continuous-true waypoint">We Analyze.</div>
    </div> 
    <div id="listWrap" class="list-wrap">
    	<div class="continuous-true waypoint">We Ideate.</div>
    	<div class="continuous-true waypoint">We Design.</div>
    	<div class="continuous-true waypoint">We Create.</div>
    </div>
    <div id="listWrap" class="list-wrap">
    	<div class="continuous-true waypoint">We Test.</div>
    	<div class="continuous-true waypoint">We Adapt.</div>
    	<div class="continuous-true waypoint">We Execute.</div>
    </div>
    <div id="listWrap" class="list-wrap">
    	<div class="continuous-true waypoint">We Report.</div>
    	<div class="continuous-true waypoint">We Learn.</div>
    	<div class="continuous-true waypoint">We Improve.</div>
    </div>
</div>

Answer 1

首先，您有多个具有相同 Id(listWrap) 的元素，您可以将其删除，然后将类名添加到您的父 div(.list-wrap-container)。

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/waypoints/4.0.1/jquery.waypoints.min.js"></script>
<div style="min-height: 2000px;" class='list-wrap-container'>
    <div class="list-wrap">
        <div class="continuous-true waypoint">We Think.</div>
        <div class="continuous-true waypoint">We Research.</div>
        <div class="continuous-true waypoint">We Involve.</div>
    </div>
    <div class="list-wrap">
        <div class="continuous-true waypoint">We Stragegize.</div>
        <div class="continuous-true waypoint">We Plan.</div>
        <div class="continuous-true waypoint">We Analyze.</div>
    </div> 
    <div class="list-wrap">
        <div class="continuous-true waypoint">We Ideate.</div>
        <div class="continuous-true waypoint">We Design.</div>
        <div class="continuous-true waypoint">We Create.</div>
    </div>
    <div class="list-wrap">
        <div class="continuous-true waypoint">We Test.</div>
        <div class="continuous-true waypoint">We Adapt.</div>
        <div class="continuous-true waypoint">We Execute.</div>
    </div>
    <div class="list-wrap">
        <div class="continuous-true waypoint">We Report.</div>
        <div class="continuous-true waypoint">We Learn.</div>
        <div class="continuous-true waypoint">We Improve.</div>
    </div>
</div>

//js代码

jQuery(function($){

    // WHAT WE DO - ACTIVATE LIST AS SCROLL BY CHANGE FONT
        var continuousElements = document.getElementsByClassName("waypoint")
            for (var i = 0; i < continuousElements.length; i++) {
                new Waypoint({
                element: continuousElements[i],
                handler: function(direction) {
                        // select the parent container
                        $(this.element).parent('.list-wrap-container').find('.gray.active').removeClass('gray active');

                        if (direction === "down") {

                            console.log(this.element.innerHTML + "down");
                            $(this.element).addClass("gray active").siblings().removeClass('active');;
                            $(this.element).removeClass("black");

                        } else if (direction === "up") { 

                            console.log(this.element.innerHTML + "up");
                            $(this.element).addClass("black");
                            $(this.element).removeClass("gray active");

                        }
                    }, offset: "50%"
                });

            }

    }); // End jQuery

//希望对你有帮助