原生JS+ CSS3创建loading加载动画；

show = function(){
    //loading dom元素
    var Div = document.createElement("div");
    Div.setAttribute("class","ui-loading");
    var chidDiv = document.createElement("div");
    chidDiv.setAttribute("class","ui-loading-mask")
    Div.appendChild(chidDiv)
    document.body.appendChild(Div)
}

hide= function(){
    var Div = document.getElementsByClassName("ui-loading");
     while(Div[0].hasChildNodes()) //当div下还存在子节点时 循环继续 
    { 
        Div[0].removeChild(Div[0].firstChild); 
    } 
    var par = Div[0].parentNode;
    par.removeChild(Div[0])
}

/*
 *    loading加载动画样式
 */
.ui-loading{
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    z-index: 998;
    background-color: rgba(0,0,0,.4);
}
.ui-loading-mask{
    width: 6px;
    height: 6px;
    border-radius: 50%;
    -webkit-animation: typing 1s linear infinite alternate;
       -moz-animation: Typing 1s linear infinite alternate;
            animation: typing 1s linear infinite alternate;
    margin: 80% auto 0; /* Not necessary- its only for layouting*/  
    position: relative;
    left: -12px;
}
@-webkit-keyframes typing{
    0%{
        background-color: rgba(255,255,255, 1);
        box-shadow: 12px 0px 0px 0px rgba(255,255,255,0.2), 
                    24px 0px 0px 0px rgba(255,255,255,0.2);
      }
    25%{ 
        background-color: rgba(255,255,255, 0.4);
        box-shadow: 12px 0px 0px 0px rgba(255,255,255,2), 
                    24px 0px 0px 0px rgba(255,255,255,0.2);
    }
    75%{ background-color: rgba(255,255,255, 0.4);
        box-shadow: 12px 0px 0px 0px rgba(255,255,255,0.2), 
                    24px 0px 0px 0px rgba(255,255,255,1);
      }
}

@-moz-keyframes typing{
   0%{
        background-color: rgba(255,255,255, 1);
        box-shadow: 12px 0px 0px 0px rgba(255,255,255,0.2), 
                    24px 0px 0px 0px rgba(255,255,255,0.2);
      }
    25%{ 
        background-color: rgba(255,255,255, 0.4);
        box-shadow: 12px 0px 0px 0px rgba(255,255,255,2), 
                    24px 0px 0px 0px rgba(255,255,255,0.2);
    }
    75%{ background-color: rgba(255,255,255, 0.4);
        box-shadow: 12px 0px 0px 0px rgba(255,255,255,0.2), 
                    24px 0px 0px 0px rgba(255,255,255,1);
      }
}

@keyframes typing{
   0%{
        background-color: rgba(255,255,255, 1);
        box-shadow: 12px 0px 0px 0px rgba(255,255,255,0.2), 
                    24px 0px 0px 0px rgba(255,255,255,0.2);
      }
    25%{ 
        background-color: rgba(255,255,255, 0.6);
        box-shadow: 12px 0px 0px 0px rgba(255,255,255,2), 
                    24px 0px 0px 0px rgba(255,255,255,0.2);
    }
    75%{ background-color: rgba(255,255,255, 0.4);
        box-shadow: 12px 0px 0px 0px rgba(255,255,255,0.2), 
                    24px 0px 0px 0px rgba(255,255,255,1);
      }
      100%{ background-color: rgba(255,255,255, 0.1);
        box-shadow: 12px 0px 0px 0px rgba(255,255,255,0.2), 
                    24px 0px 0px 0px rgba(255,255,255,1);
      }
}