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JMRI's web pages and help screens are written in a simple subset of HTML, the language that powers the web. The most important part of the content is the plain text that people will read, and the additional formatting information is kept very minimal. To update a JMRI web page, you edit these directly on GitHub web or on your computer with a plain text editor.
Using a word processing app like MS Word or Front Page to edit these .shtml documents is
not a good idea because they will probably add in their own proprietary formatting codes that
will mess things up, possibly even to the point of being unusable by JMRI. Also, don't rename
existing files, or make changes to the formatting information at the top or bottom.
So you may concentrate on making editorial changes to the text in the main body of a file, which is really what the readers are paying attention to anyway.
To get started, you can drill down inside your computer's JMRI program files to the folder
for the DecoderPro manual. On a Windows system, the location for this folder looks something
like this --
C:\ProgramFiles\JMRI\help\en\manual. In this folder is a file
index.shtml. Open that file with a text editor and look around. If you
change something, you can then open the page in the JMRI help system and see how it looks
(either keep a backup in case you want the original page back, or you can reinstall JMRI to
The most simple changes are just ones to the text itself: To add a sentence or fix a wording, you just do that with the editor. To add a break between paragraphs, e.g. to add a new paragraph, you insert a "tag" that tells JMRI or a browser to insert a paragraph break.
<Alt>key and the
<Print Screen>key at the same time. (Note: Depending on your keyboard, you might need to press the
<Function-Lock>key as well.) This puts the image on your "clipboard" and you can paste it into an image-editing program such as Window's Paint or Photoshop.
Print Screen>> and <
Alt + Print Screen> keys you can install KSnapshot or your favorite application to do your screen grabbing.
<Apple + Shift + 4>key. When you release them at the same time, the cursor becomes a plus sign, and you can drag it around the area you want. When you let go, you will have an image file on your desktop.
On macOS we nowadays often use Evernote Skitch to grab and touch
up screen shots. Here's an example of that style:
We also love IrFanView for screenshots, and it is free. With it, you can also include your mouse cursor in your snapshot. You can also take a series of shots easily, and even make a slideshow of them. You can tell it what file format you want the image files to be AND where you want them to be saved before you take the shot, and that makes it easier to work with them in a program like Paint or Photoshop.
If you understand this, you are ready to help us update the many JMRI documents that we use for both the JMRI website and for the Help files in a next software build.
When you submit your changes to be included in future JMRI releases, they are given a quick check and then merged into the previous content. The check is done by using GitHub tools to find the parts of the file that have been changed.