HTML5 五彩圆环Loading加载动画实现教程

HTML代码：

<div id=”hold”></div>

CSS代码：

@-webkit-keyframes spin {
  from {
    -webkit-transform: rotate(360deg);
    transform: rotate(360deg);
  }

  to {
    -webkit-transform: rotate(0deg);
    transform: rotate(0deg);
  }
}

@keyframes spin {
  from {
    -webkit-transform: rotate(360deg);
    transform: rotate(360deg);
  }

  to {
    -webkit-transform: rotate(0deg);
    transform: rotate(0deg);
  }
}
@-webkit-keyframes osc {
  0% {
    -webkit-transform: scale(0.5);
    transform: scale(0.5);
    opacity: 0;
  }

  50% {
    -webkit-transform: scale(1.5);
    transform: scale(1.5);
    opacity: 1;
  }

  100% {
    -webkit-transform: scale(0.5);
    transform: scale(0.5);
    opacity: 0;
  }
}
@keyframes osc {
  0% {
    -webkit-transform: scale(0.5);
    transform: scale(0.5);
    opacity: 0;
  }

  50% {
    -webkit-transform: scale(1.5);
    transform: scale(1.5);
    opacity: 1;
  }

  100% {
    -webkit-transform: scale(0.5);
    transform: scale(0.5);
    opacity: 0;
  }
}
@-webkit-keyframes rainbow {
  0% {
    background: #df2020;
  }

  25% {
    background: #80df20;
  }

  50% {
    background: #20dfdf;
  }

  75% {
    background: #7f20df;
  }

  100% {
    background: #df2020;
  }
}
@keyframes rainbow {
  0% {
    background: #df2020;
  }

  25% {
    background: #80df20;
  }

  50% {
    background: #20dfdf;
  }

  75% {
    background: #7f20df;
  }

  100% {
    background: #df2020;
  }
}

JS代码如下：

var num = 7,
    ang = 360/num,
    rad = num*5;

function setup(){
  for(var i=0; i<num; i++){
    var button = document.createElement('div');
    button.className = "dot"+i+" dot";
    button.style.top = rad*Math.cos(ang*i*Math.PI/180)-10+"px";
    button.style.left = rad*Math.sin(ang*i*Math.PI/180)-10+"px";
    button.style.backgroundColor = "hsla("+ang*i+", 50%, 50%, 1)";

    button.style.webkitAnimation = 
      "osc 2s ease-in-out infinite "+i/(num/2)+"s, rainbow 8s infinite "+i/(num/2)+"s";
    button.style.animation = 
      "osc 2s ease-in-out infinite "+i/(num/2)+"s, rainbow 8s infinite "+i/(num/2)+"s, spin 1s infinite";

    document.getElementById("hold").appendChild(button);
  }
}