javascript tooltip

 转自http://sixrevisions.com/tutorials/javascript_tutorial/create_lightweight_javascript_tooltip/

 

 

 

var tooltip=function(){
 var id = 'tt';
 var top = 3;
 var left = 3;
 var maxw = 300;
 var speed = 10;
 var timer = 20;
 var endalpha = 95;
 var alpha = 0;
 var tt,t,c,b,h;
 var ie = document.all ? true : false;
 return{
  show:function(v,w){
   if(tt == null){
    tt = document.createElement('div');
    tt.setAttribute('id',id);
    t = document.createElement('div');
    t.setAttribute('id',id + 'top');
    c = document.createElement('div');
    c.setAttribute('id',id + 'cont');
    b = document.createElement('div');
    b.setAttribute('id',id + 'bot');
    tt.appendChild(t);
    tt.appendChild(c);
    tt.appendChild(b);
    document.body.appendChild(tt);
    tt.style.opacity = 0;
    tt.style.filter = 'alpha(opacity=0)';
    document.onmousemove = this.pos;
   }
   tt.style.display = 'block';
   c.innerHTML = v;
   tt.style.width = w ? w + 'px' : 'auto';
   if(!w && ie){
    t.style.display = 'none';
    b.style.display = 'none';
    tt.style.width = tt.offsetWidth;
    t.style.display = 'block';
    b.style.display = 'block';
   }
  if(tt.offsetWidth > maxw){tt.style.width = maxw + 'px'}
  h = parseInt(tt.offsetHeight) + top;
  clearInterval(tt.timer);
  tt.timer = setInterval(function(){tooltip.fade(1)},timer);
  },
  pos:function(e){
   var u = ie ? event.clientY + document.documentElement.scrollTop : e.pageY;
   var l = ie ? event.clientX + document.documentElement.scrollLeft : e.pageX;
   tt.style.top = (u - h) + 'px';
   tt.style.left = (l + left) + 'px';
  },
  fade:function(d){
   var a = alpha;
   if((a != endalpha && d == 1) || (a != 0 && d == -1)){
    var i = speed;
   if(endalpha - a < speed && d == 1){
    i = endalpha - a;
   }else if(alpha < speed && d == -1){
     i = a;
   }
   alpha = a + (i * d);
   tt.style.opacity = alpha * .01;
   tt.style.filter = 'alpha(opacity=' + alpha + ')';
  }else{
    clearInterval(tt.timer);
     if(d == -1){tt.style.display = 'none'}
  }
 },
 hide:function(){
  clearInterval(tt.timer);
   tt.timer = setInterval(function(){tooltip.fade(-1)},timer);
  }
 };
}();

 

 

 

 

#tt {
 position:absolute;
 display:block;
 background:url(images/tt_left.gif) top left no-repeat;
 }
 #tttop {
 display:block;
 height:5px;
 margin-left:5px;
 background:url(images/tt_top.gif) top right no-repeat;
 overflow:hidden;
 }
 #ttcont {
 display:block;
 padding:2px 12px 3px 7px;
 margin-left:5px;
 background:#666;
 color:#fff;
 }
#ttbot {
display:block;
height:5px;
margin-left:5px;
background:url(images/tt_bottom.gif) top right no-repeat;
overflow:hidden;
}

 

使用：

onmouseover="tooltip.show('Testing  123 ', 200);"
onmouseout="tooltip.hide();"