组件成果如下:
技术亮点:
1.封装分页组件,不须要在内部页面保护公共数据,只须要在公共数据局部保护该分页器实例自身即可2.所有的数据都在外部实现计算,存储, 多个分页器实例都是新的单例(工厂模式),都是独立的存在,不必放心分页器之间的数据粘连
开发思路:
次要用了setter getter以及事件侦听抛发机制,及时的实现数据视图的双向通信
内部应用示例:
留神点:
1.属性写在办法里面是ES7的写法,而webpack打包时,必须要装babel的plugin能力打包,否则出错。所以这里长期的解决方案是在构造函数内及init函数内创立类中须要调用的属性 2.如果有其余需要,则内部能够操作扭转pageSize,total,currentPage三个属性的扭转
组件代码如下:
export default class paginations extends EventTarget{ constructor(_eventType) {//初始化时须要申明自定义事件类型,指定数据抛发的指向对象 super(); this.elem = this.createElem();//放分页器的容器 this.elem.className="paganitionCon" this.elem.addEventListener("click", (e) => this.clickHandler(e)); this.eventType = _eventType; this.init();//初始化款式,没有数据 this.render(); this.hightlight(); } init() { this._pageSize = 3;//每页显示条目个数 this._total = 0;//总条目数 this._currentPage = 1;//当前页数 this.pageCount = Math.ceil(this.total / this.pageSize);//须要渲染的页数 } createElem(){ if(this.elem) return this.elem; let div=document.createElement("div"); return div; } appendTo(parent){ if(typeof parent==="string")parent=document.querySelector(parent); parent.appendChild(this.elem); } set total(value) {//当总条数扭转时,total扭转 this._total = value; this.pageCount = Math.ceil(this.total / this.pageSize); this.render(); this.hightlight(); } get total() { return this._total; } set pageSize(value) {//每页显示条目个数扭转时,触发扭转 this._pageSize = value; this.pageCount = Math.ceil(this.total / this.pageSize); this.render(); this.hightlight(); } get pageSize() { return this._pageSize; } set currentPage(value) { this._currentPage = value; this.render(); this.hightlight(); } get currentPage() { return this._currentPage; } render() { this.elem.innerHTML = ""; this.elem.innerHTML = ` <ul class="pagination pagination-sm no-margin pull-right" id="paginationModule"> <li><a href="javascript:;" class="left">«</a></li> ${(function (pageCount) { var arr = []; for (let i = 1; i <= pageCount; i++){ arr.push("<li><a href='javascript:void(0)'>" + i + "</a></li>"); } return arr.join(""); })(this.pageCount)} <li><a href="javascript:;" class="right">»</a></li> </ul>`; } clickHandler(e) { if (e.target.nodeName !== "A") return; switch (e.target.className) { case "": this.currentPage = Number(e.target.textContent); break; case "left": if (this.currentPage > 1) this.currentPage--; else this.currentPage = 1; break; case "right": if (this.currentPage < this.pageCount) this.currentPage++; else this.currentPage = this.pageCount; break; } this.dispatch(this.currentPage); } hightlight() { this.liArr = this.elem.querySelectorAll("li");//存储所有的页数对应的li if (this.prev) this.prev.className = "";//给prev设置为active,prev是指须要高亮的页数 if (this.currentPage) {//当数据全副删除完,则无高亮成果 this.prev = this.liArr[this.currentPage]; this.prev.className = "active"; } } dispatch(currentPage) { let evt = new Event(this.eventType); evt.data = { currentPage } this.dispatchEvent(evt); }}