javascript - 单击时在 div 处切换 z-index

Question

我正在尝试遍历绝对定位并具有 z 索引的子级 div。单击按钮时，我希望 z-index 增加，因此它几乎像一个循环一样工作。所以在每次点击时，我希望当前可见的 div 具有较低的 z 索引，因此一次只有一个 div 可见。

$(function() {
    $('button').click(function(){
        //.three sholed take the place of .one and .two should jump up one step. i want this to be repeatable.
    });
});

body {
    margin:0;
    padding:0;
}
.holder {
    width: 100px;
    height:100px;
    border:1px solid #000000;
}

.holder div {
    width: 100px;
    height: 100px;
    position:absolute;
    top:0;
    left:0;
}

.one {
    background:red;
    z-index:1;
}
.two {
    background:green;
    z-index:2;
}
.three {
    background: blue;
    z-index:3;
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.0/jquery.min.js"></script>
<div class="holder">
    <div class="one">1</div>
    <div class="two">2</div>
    <div class="three">3</div>
</div>
<button>click</button>

Answer 1

使用 jquery 将一个类添加到应具有所需索引/在单击时可见的元素

$("button").click(function(){
  $(".current").removeClass("current").next().addClass("current")
});

body {
    margin:0;
    padding:0;
}
.holder {
    width: 100px;
    height:100px;
    border:1px solid #000000;
}

.holder div {
    width: 100px;
    height: 100px;
    position:absolute;
    top:0;
    left:0;
    z-index:0; /*init z-index*/
}
.holder div.current{z-index:1;} /*only this DIV will be visible*/
.one {
    background:red;
}
.two {
    background:green;
}
.three {
    background: blue;
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="holder">
    <div class="one current">1</div>
    <div class="two">2</div>
    <div class="three">3</div>
</div>
<button>click</button>

如果要循环播放

$("button").click(function(){
  if($(".holder >div:last-child").hasClass("current")){
     $(".holder >div:last-child").removeClass("current");
     $(".holder >div:first-child").addClass("current");
  }else{
     $(".current").removeClass("current").next().addClass("current");
  }
});

body {
    margin:0;
    padding:0;
}
.holder {
    width: 100px;
    height:100px;
    border:1px solid #000000;
}

.holder div {
    width: 100px;
    height: 100px;
    position:absolute;
    top:0;
    left:0;
    z-index:0; /*init z-index*/
}
.holder div.current{z-index:1;} /*only this DIV will be visible*/
.one {
    background:red;
}
.two {
    background:green;
}
.three {
    background: blue;
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="holder">
    <div class="one current">1</div>
    <div class="two">2</div>
    <div class="three">3</div>
</div>
<button>click</button>