Django打造大型企业官网（六）

4.9.根据轮播图个数修改小圆点数量

src/js/index.js

function banner() {
    this.bannerwidth = 798;
}

banner.prototype.initbanner = function () {
    var self = this;
    this.bannerul.css({
        "width":self.bannerwidth*self.bannercount
    })
};

banner.prototype.initpagecontrol = function () {
  var self = this;
  var pagecontrol = $(".page-control");
  for (var i=0;i<self.bannercount;i++){
      var circle = $("<li></li>");
      pagecontrol.append(circle);
      if (i === 0){
          circle.addclass("active");
      }
  }
  pagecontrol.css({"width":self.bannercount*12+8*2+16*(self.bannercount-1)});
};

banner.prototype.run = function () {
    this.initbanner();
    this.initpagecontrol();
    this.loop();
    this.listenarrowclick();
};

4.10.小圆点点击事件和自动更新当前选中的小圆点

src/js/index.js

function banner() {
        this.pagecontrol = $(".page-control");
};

banner.prototype.animate = function () {
    var self = this;
    self.bannerul.animate({"left":-798*self.index},500);
    // 通过index获取到当前的li标签，添加active样式，兄弟li标签移除active样式
    self.pagecontrol.children('li').eq(self.index).addclass("active").siblings().removeclass("active");
};

banner.prototype.listenpagecontrol = function () {
    var self = this;
    self.pagecontrol.children("li").each(function (index,obj) {
        $(obj).click(function () {
            self.index = index;
            self.animate();
        });
    });
};

banner.prototype.run = function () {
    this.listenbannerhover();
};

src/css/scss.css

.header{
     z-index: 100;



.banner-group{

    overflow:hidden;
    z-index: 0;

4.11.实现自动循环无限轮播

src/js/index.js

function banner() {
    this.index = 1;
};

banner.prototype.initbanner = function () {
    var self = this;
    //实现无限轮播，原理：123-->>31231，在首尾克隆一张
    var firstbanner = self.lilist.eq(0).clone();
    var lastbanner = self.lilist.eq(self.bannercount-1).clone();
    self.bannerul.append(firstbanner);
    self.bannerul.prepend(lastbanner);
    self.bannerul.css({
        "width":self.bannerwidth*(self.bannercount+2),
        "left":-self.bannerwidth,
    });
};

banner.prototype.animate = function () {
    var self = this;
    self.bannerul.animate({"left":-798*self.index},500);
    //小圆点的active
    var index = self.index;
    if(index === 0){
        index = self.bannercount-1;
    }else if(index === self.bannercount+1){
        index = 0;
    }else{
        index = self.index - 1;
    }
    // 通过index获取到当前的li标签，添加active样式，兄弟li标签移除active样式
    self.pagecontrol.children('li').eq(index).addclass("active").siblings().removeclass("active");
};

banner.prototype.loop = function(){
    var self = this;
    this.timer = setinterval(function () {
        if(self.index >= self.bannercount+1){
            self.bannerul.css({
                "left":-self.bannerwidth,
            });
            self.index = 2;
        }else{
            self.index++;
        }
        self.animate();
    },2000);
};

4.12.左右牵头切换实现循环轮播

src/js/index.js

banner.prototype.listenarrowclick = function () {
    var self = this;
    self.leftarrow.click(function () {
       if(self.index === 0){
           self.bannerul.css({
              "left":-self.bannercount*self.bannerwidth,
           });
           self.index = self.bannercount - 1;
       }else{
           self.index --;
       }
       self.animate();
    });

    self.rightarrow.click(function () {
       if(self.index === self.bannercount + 1){
           self.bannerul.css({
              "left":-self.bannerwidth,
           });
           self.index = 2;
       }else{
           self.index ++;
       }
       self.animate();
    });
};