原生JavaScript写出Tabs标签页的实例代码

Z时代
2024-01-10
分类：综合

最近在重新学习JavaScript，手写了一个tabs标签页。

话不多说，直接开始。

首先，是前端页面。

图1 tabs

先来把tabs分解一下：

图2 tabs分解

首先，一个大的框div，上面红色的框是导航栏nav，导航栏里是一个无序列表ul，里面三个li标签（黄色的框），li标签里两个绿色标签是两个span，一个用来放导航的名字，一个用来放导航关闭的icon，右边是一个button，用来添加新的导航栏及内容；下方是导航栏的内容section。

导航tabs.html代码如下：


<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<body>
  <main>
    <div class="tabsbox" id="tab">
      <!-- tab标签 -->
      <nav class="firstnav">
        <ul>
          <li class="liactive"><span>测试1</span><span class="icon-guanbi">X</span></li>
          <li><span>测试2</span><span class="icon-guanbi">X</span></li>
          <li><span>测试3</span><span class=" icon-guanbi">X</span></li>
        </ul>
        <div class="tabadd">
          <span>+</span>
        </div>
      </nav>
      <!-- tab内容 -->
      <div class="tabscon">
        <section class="conactive">测试内容1</section>
        <section>测试内容2</section>
        <section>测试内容3</section>
      </div>
    </div>
  </main>
  <script src="js/tabs.js"></script>
</body>
</html>
<style>
 * {
  margin: 0;
  padding: 0;
}
ul li {
  list-style: none;
}
main {
  width: 960px;
  height: 500px;
  border-radius: 10px;
  margin: 50px auto;
}
main h4 {
  height: 100px;
  line-height: 100px;
  text-align: center;
}
.tabsbox {
  width: 900px;
  margin: 0 auto;
  height: 400px;
  border: 1px solid lightsalmon;
  position: relative;
}
nav ul {
  overflow: hidden;
}
nav ul li {
  float: left;
  width: 100px;
  height: 50px;
  line-height: 50px;
  text-align: center;
  border-right: 1px solid #ccc;
  position: relative;
}
nav ul li.liactive {
  border-bottom: 2px solid #fff;
  z-index: 9;
}
#tab input {
  width: 80%;
  height: 60%;
}
nav ul li span:last-child {
  position: absolute;
  user-select: none;
  font-size: 12px;
  top: -18px;
  right: 0;
  display: inline-block;
  height: 20px;
}
.tabadd {
  position: absolute;
  /* width: 100px; */
  top: 0;
  right: 0;
}
.tabadd span {
  display: block;
  width: 20px;
  height: 20px;
  line-height: 20px;
  text-align: center;
  border: 1px solid #ccc;
  float: right;
  margin: 10px;
  user-select: none;
}
.tabscon {
  width: 100%;
  height: 300px;
  position: absolute;
  padding: 30px;
  top: 50px;
  left: 0px;
  box-sizing: border-box;
  border-top: 1px solid #ccc;
}
.tabscon section,
.tabscon section.conactive {
  display: none;
  width: 100%;
  height: 100%;
}
.tabscon section.conactive {
  display: block;
}
</style>

由于给导航栏增删查改的js代码很多，我单独用一个js文件写tabs.js，在tabs.html里引用就行。

实现的导航栏功能有：

　　1）导航栏的切换功能

2）增加导航栏的功能

3）删除导航栏的功能

tabs.js代码如下：


var that;
class Tab {
  constructor(id){
    that = this;
    //获取元素
    this.main = document.querySelector(id);
    this.add = this.main.querySelector('.tabadd');
    //li的父元素
    this.ul = this.main.querySelector('.firstnav ul:first-child');
    //section的父元素
    this.fsection = this.main.querySelector('.tabscon');
    this.init();
  }
  //初始化操作
  init(){
    this.updateNode();
    this.add.onclick = this.addTab;
    for(let i = 0;i<this.lis.length;i++){
      this.lis[i].index = i;
      this.lis[i].onclick = this.toggleTab;
      this.remove[i].onclick = this.removeTab;
      this.spans[i].ondblclick = this.editTab;
      this.sections[i].ondblclick = this.editTab;
    }
  }
  //获取li跟section
  updateNode(){
    this.lis = this.main.querySelectorAll('li');
    this.sections = this.main.querySelectorAll('section');
    this.remove = this.main.querySelectorAll('.icon-guanbi');
    this.spans = this.main.querySelectorAll('.firstnav li span:first-child')
  }
  //1.切换功能
  toggleTab(){
    that.clearClass();
    this.className = 'liactive';
    that.sections[this.index].className = 'conactive';
  }
  clearClass(){
    for(let i = 0;i<this.lis.length;i++){
      this.lis[i].className = '';
      this.sections[i].className = '';
    }
  }
  //2.添加功能
  addTab(){
    that.clearClass();
    //1)添加li元素和section
    var random = Math.random()
    var li = '<li class="liactive"><span>新选项卡</span><span class="iconfont icon-guanbi">X</span></li>';
    var section = '<section class="conactive">'+random+'</section>';
    //2）把两个元素添加到对应的父级元素中
    that.ul.insertAdjacentHTML('beforeend',li);
    that.fsection.insertAdjacentHTML('beforeend',section);
    that.init();
  }
  //3.删除功能
  removeTab(e){
    e.stopPropagation();
    var index = this.parentNode.index;
    console.log(index);
    //删除对应节点
    that.lis[index].remove();
    that.sections[index].remove();
    //删除后及时更新页面中的节点
    that.init();
    //如果当前页面有选中状态，就不用执行下面的步骤
    if(document.querySelector('.liactive')) return;
    //让index前一个处于选中状态
    index--;
    that.lis[index] && that.lis[index].click();
  }
  //4.修改功能
  editTab(){
    let str = this.innerHTML;
    // console.log(str);
    //禁止双击选中文字
    window.getSelection ? window.getSelection().removeAllRanges() : document.selection.empty();
    this.innerHTML='<input type="text">'
    let input = this.children[0];
    input.value = str;
    input.select();
    //input失去焦点后变回span
    input.onblur = function(){
      this.parentNode.innerHTML= this.value;
    }
    //按回车也能
    input.onkeyup = function(e){
      if(e.keyCode == 13){
         this.blur();//获得焦点
      }
    }
  }
}
 new Tab('#tab');
// tab.init();