The following function may be used to resize the IFRAME dynamically.

IFrameBox.prototype.Resize = function(wdth)
{
      if( IFrameBox.IsBrowserIE() )
      {
            var div = frames[this.id].document.getElementById(this.DivID);
            if(!wdth)
                  this.IFrame.style.width = div.offsetWidth;
            else
                  this.IFrame.style.width = wdth;
            this.IFrame.style.height = div.offsetHeight;
      }
      else
      {
            this.IFrame.style.width = this.Width;
            this.IFrame.style.height = this.Height;
      }
}

The following function may be used to place an IFRAME at required positions on the web page:

IFrameBox.prototype.PlaceAt = function(x, y)
{
            this.IFrame.style.position = "absolute";
            this.IFrame.style.left = x;
            this.IFrame.style.top = y;
}

The following function tests whether the current IFRAME is in the visible state or not:

IFrameBox.prototype.IsVisible = function()
{
      var ifrm = document.getElementById(this.id);     

      if( ifrm.style.visibility == "visible" && ifrm.style.width > 0 )
            return true;
      else
            return false;
}

The following function makes an IFRAME visible (make sure that it uses some of the functions defined above).

IFrameBox.prototype.Show = function(evt, msg, wdth)
{
      if( this.IsVisible() )
            return;                

      var div = frames[this.id].document.getElementById(this.DivID);
      div.innerHTML=msg;
      this.Resize(wdth);     

      if(evt)
      {
            this.PlaceAt((evt.x +10),(evt.y +10));
      }           

      this.IFrame.style.visibility = "visible";
      this.IFrame.style.zIndex = "999999";
}

Hiding an IFRAME is the simplest of all. You can define the function as follows:

IFrameBox.prototype.Hide = function()
{     
      this.IFrame.style.visibility = "hidden";
      this.IFrame.style.width = 0;
      this.IFrame.style.height = 0;
}

I leave it to the programmers to further extend the library to suit their needs.  The above set of functions is very suitable for presenting eye-catching tool tips on your web page.  As the tool tips are based on IFRAME, they are naturally displayed ahead of any windowed controls (like dropdown lists and so on).