Programming

Overview

This applet is a simple text scrolling applet. It is very configurable, and thus quite useful. It is written to use Java 1.1 to ensure it will run on the maximum number of web browsers. Here are a couple of demonstrations:

You need a Java-capable web browser to see the applet.

You need a Java-capable web browser to see the applet.

So, what makes TextScroll so much better than all the other scrolling applets out there? I’ve had a good look through Jars and Gamelan, and there’s been some impressive work done. Unfortunately, no one is giving away the good ones. Even the ones that are for sale don’t come with the source code. So, the first two advantages of TextScroll are that it’s free and it comes with source code. It supports features not even found in the commercial scrollers, including:

  • dynamic background colors
  • dynamic foreground colors
  • Multiple font faces, sizes, and styles (bold, italic)
  • Variable scroll speed
  • Optional automatic line wrapping
  • Ability to open URLs in the same or different frames/windows
  • “Refresh” ability (loads asynchronously)
  • Professional appearance
  • Optional “heading” panel on the left side

And more. Note that most configuration options can be changed on the fly, in the middle of a presentation by embedding commands right in the text file. The applet gets its data from a separate text file, so you don’t have to clutter up your HTML pages by putting the actual text in a bunch of <PARAM> tags. This also makes it much easier for multiple pages to display the same presentation.

Versions 2.1 and above include a feature called directives. See the complete directives’ documentation and the HOWTO for more information.

Note – You must note one thing if you are writing text content for this applet. It is very important that you realize that if you use the automatic line wrapping, you cannot specify a single newline. Blank lines (i.e., new paragraphs) will still be recognized and displayed, but you cannot force a single newline. If you want to specify where the lines wrap, that is, if you want the lines to wrap in the same places they wrap in the text file, then you must include the following <PARAM> tag in the HTML file:


<PARAM NAME="wraptext" value="false">

Source Code

The source code for this project is available for downloading. Version 2.6 has increased the number of classes. The project became too complex to keep contained in a single class. The entire applet now consists of 4 classes:

  • DataLoader.java
  • DirectiveManager.java
  • LineWrapManager.java
  • TextScroll.java

Please read the disclaimer at the top of the file before distributing this code.

Binary

I’ve had requests to make the binary for this applet available, since not everyone has the environment for compiling the .java file offered in the Source Code section. This applet has 4 binary .class files associated with it, and you will need them all:

  • DataLoader.class
  • DirectiveManager.class
  • LineWrapManager.class
  • TextScroll.class

Javadoc Documentation

You can also view the Javadoc generated documentation online:

  • DataLoader
  • DirectiveManager
  • LineWrapManager
  • TextScroll

Licensing

If you want to use this applet on your page(s), I am releasing it under an extremely slack license. All I ask is that you do not claim you wrote it. You can use it for personal use, educational use, or commercially, as long as you do not claim you wrote it. I would appreciate it if you would mention me somewhere on a credits page, but I don’t require it. I’m releasing this for people like me who want a nice tool for free. Enjoy.