February 14, 2000 - Creating A Banner | WebReference

February 14, 2000 - Creating A Banner

Yehuda Shiran February 14, 2000
Creating A Banner
Tips: February 2000

Yehuda Shiran, Ph.D.
Doc JavaScript

Creating a banner in Netscape Navigator is very tricky. We have already showed in our tip from January 30, 2000 how to write into a banner container. But this is only one of the difficulties. There are several other items that you need to pay attention to:

SPAN element must be placed in absolute positions. Notice the STYLE attribute of our SPAN element: 
<SPAN ID="banner" STYLE="position: absolute;"><I>the banner is loading</I></SPAN>

  • Timing. You have to load the banner only after the page completes its loading. You do it by specifying the event handler: 
    onload = start;

    where

    • start() is the following function: 
    function start() {
  display("banner", "Navigator behaves totally differently from Explorer");
}

  • Open and Close Document. You can't just write to the banner. You have to open it, write to it, and close it: 
    with (document[id].document) {
      open();
      write(str);
      close();
    }

    • Again, I cannot stress enough how much the above topics are impoartant. Here is a banner script. Try to omit some features and observe its consequences. 

    <HTML>
<HEAD>
<TITLE>Title Here</TITLE>
<SCRIPT LANGUAGE="JavaScript1.2">
<!--
var NS4 = (document.layers) ? 1 : 0;
var IE4 = (document.all) ? 1 : 0;
onload = start;
function start() {
  display("banner", "Navigator behaves totally differently from Explorer");
}
function display(id, str) {
  if (NS4) {
    with (document[id].document) {
      open();
      write(str);
      close();
    }
  } else {
    document.all[id].innerHTML = str;
  }
}
// -->
</SCRIPT>
</HEAD>
<BODY>
<SPAN ID="banner" STYLE="position: absolute;"><I>the banner is loading</I></SPAN><BR><BR>
</BODY>
</HTML>

    Learn more about text banners in Column 3, Rotating Text Banners.