jquery floating fixed layer plug-in usage example at any position_jquery

The example in this article describes the usage of the jquery floating fixed layer plug-in at any position. Share it with everyone for your reference. The specific analysis is as follows:

Note: You can make the specified layer float to any position on the web page. When the scroll bar scrolls, it will remain at the current position and will not flicker

2009-06-10 modification: Re-modify the way the plug-in implements fixed floating layers, using a large fixed layer for positioning
2009-07-16 Modification: Fixed the problem of being unable to be fixed on top under IE6

09-11-5 modification: When customizing the absolute position of the layer, add the judgment when top is a null value
This time the method was stolen from Tianya’s new page
After many tests, there are basically no bugs~

Call:

1 Call without parameters: float in the lower right corner by default

$("#id").floatdiv();

2 Built-in fixed position float

//右下角  
$("#id").floatdiv("rightbottom");  
//左下角  
$("#id").floatdiv("leftbottom");  
//右下角  
$("#id").floatdiv("rightbottom");  
//左上角  
$("#id").floatdiv("lefttop");  
//右上角  
$("#id").floatdiv("righttop");  
//居中  
$("#id").floatdiv("middle");  

Added four new fixed position methods

middletop (centered at the top), middlebottom (centered at the bottom), leftmiddle, rightmiddle

3 Customized position float

$("#id").floatdiv({left:"10px",top:"10px"});
With the above parameters, set the floating layer at 10 pixels from the left and 10 pixels from the top

jQuery.fn.floatdiv=function(location){  
  //判断浏览器版本  
  var isIE6=false;  
  var Sys = {};  
  var ua = navigator.userAgent.toLowerCase();  
  var s;  
  (s = ua.match(/msie ([\d.]+)/)) ? Sys.ie = s[1] : 0;  
  if(Sys.ie && Sys.ie=="6.0"){  
    isIE6=true;  
  }  
  var windowWidth,windowHeight;//窗口的高和宽  
  //取得窗口的高和宽  
  if (self.innerHeight) {  
    windowWidth=self.innerWidth;  
    windowHeight=self.innerHeight;  
  }else if (document.documentElement&&document.documentElement.clientHeight) {
    windowWidth=document.documentElement.clientWidth;  
    windowHeight=document.documentElement.clientHeight;  
  } else if (document.body) {  
    windowWidth=document.body.clientWidth;  
    windowHeight=document.body.clientHeight;  
  }  
  return this.each(function(){  
    var loc;//层的绝对定位位置  
    var wrap=$("<div></div>");  
    var top=-1;  
    if(location==undefined || location.constructor == String){  
      switch(location){  
        case("rightbottom")://右下角  
          loc={right:"0px",bottom:"0px"};  
          break;  
        case("leftbottom")://左下角  
          loc={left:"0px",bottom:"0px"};  
          break;   
        case("lefttop")://左上角  
          loc={left:"0px",top:"0px"};  
          top=0;  
          break;  
        case("righttop")://右上角  
          loc={right:"0px",top:"0px"};  
          top=0;  
          break;  
        case("middletop")://居中置顶  
          loc={left:windowWidth/2-$(this).width()/2+"px",top:"0px"};  
          top=0;  
          break;  
        case("middlebottom")://居中置低  
          loc={left:windowWidth/2-$(this).width()/2+"px",bottom:"0px"};  
          break;  
        case("leftmiddle")://左边居中  
          loc={left:"0px",top:windowHeight/2-$(this).height()/2+"px"};  
          top=windowHeight/2-$(this).height()/2;  
          break;  
        case("rightmiddle")://右边居中  
          loc={right:"0px",top:windowHeight/2-$(this).height()/2+"px"};  
          top=windowHeight/2-$(this).height()/2;  
          break;  
        case("middle")://居中  
          var l=0;//居左  
          var t=0;//居上  
          l=windowWidth/2-$(this).width()/2;  
          t=windowHeight/2-$(this).height()/2;  
          top=t;  
          loc={left:l+"px",top:t+"px"};  
          break;  
        default://默认为右下角  
          location="rightbottom";  
          loc={right:"0px",bottom:"0px"};  
          break;  
      }  
    }else{  
      loc=location;  
      alert(loc.bottom);  
      var str=loc.top;  
      //09-11-5修改：加上top为空值时的判断  
      if (typeof(str)!= 'undefined'){  
        str=str.replace("px","");  
        top=str;  
      }  
    }  
    /*fied ie6 css hack*/  
    if(isIE6){  
      if (top>=0)  
      {  
        wrap=$("<div style=\"top:e&shy;xpression(documentElement.scrollTop+"+top+");\"></div>");  
      }else{  
        wrap=$("<div style=\"top:e&shy;xpression(documentElement.scrollTop+documentElement.clientHeight-this.offsetHeight);\"></div>");
      }  
    }  
    $("body").append(wrap);  
    wrap.css(loc).css({position:"fixed",z_index:"999"});  
    if (isIE6)  
    {  
      wrap.css("position","absolute");  
      //没有加这个的话，ie6使用表达式时就会发现跳动现象  
      //至于为什么要加这个，还有为什么要加nothing.txt这个，偶也不知道，希望知道的同学可以告诉我  
      $("body").css("background-attachment","fixed").css("background-image","url(n1othing.txt)");  
    }  
    //将要固定的层添加到固定层里  
    $(this).appendTo(wrap);  
  });  
};

Click here for the complete example codeDownload from this site.

I hope this article will be helpful to everyone’s jQuery programming.