I have started you along this path and I hope you will find the exercise useful.
First question: are you using Windows/Linux/Mac?
My advice refers to Linux notation but the tools I refer to can be used across Window/Linux/Mac.
The reason I decided to adopt a toolchain integrated with Scribus was to develop a more agile workflow to accommodate frequent changes in documents to be published. As you know Scribus can be used as a dedicated content editor but it is not ideal since we have to dive into properties windows when significant changes are required. It was for this reason that I decided for my purposes to leverage Scribus as a layout engine and not as a content editor.
You have started by installing Atom. It is quite easy to install Atom packages which extend Atom's functionality. At current count there are over 7,800 packages to choose from.
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Now to first answer your immediate questions.
(1) Any markdown file should end with the extension *.md and not *.txt. You will see no effect with a text file.
(2) You need to install an Atom package - Markdown Preview Enhanced.
(3) Although you may have installed packages you will need to Toggle to see the Preview Window (WYSIWYG) in the right pane before it will be sent to Scribus.
(4) Note the advice below to run Window:Reload after installation of packages to refresh Atom, before the packages are seen in Packages menu. And packages need to be toggled to enable them.
(5) Be patient about the final stage pushing Atom content into Scribus. Learn the pre processing stages first. Further advice will follow on Atom -> Scribus link.
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Let us start by installing a few useful Atom packages.
In addition to Atom you are recommended to install Pandoc which is a generic document converter.
It is helpful if you start by installing the Atom package
Project Manager Project Viewer. This allows multiple project assets to be viewed in Atom left pane.
You can navigate through all Packages by going to Atom topbar > Packages and using the search facility.
And here ..
https://atom.io/packagesBut with the large number of packages available to choose from it is easier for a new user to narrow down the search options by a google search for a required feature. Use a google pattern in your browser .. some examples follow ...
Atom NEAR markdown .. you will also find a galaxy of tutorials
Atom NEAR footnote
Atom NEAR endnote
Atom NEAR snippets
If you navigate to topbar View > Toggle Tree View you can show/hide the left navigation panel.
Referring to my own history of installation commands I had installed
Project Manager Project Viewer by running this command ..
apm install project-managerapm install project-viewer
Late edit: Advice later in this thread was updated to install packages project-viewer and atom-material-ui
In the command terminal the installation is confirmed.
Now after installation of any package the Atom instance has to be reloaded before the installed package is seen in the topbar Packages menu.
In Linux we can reload by hitting the hot keys [Ctrl + Shift + P]
or in Atom .. topbar > Packages > Command Palette > Toggle
Either usage will bring up a package search window.
Now type in "Window" and choose the option Window:Reload
This will reload Atom and now the package
Project Manager Project Viewer will be seen to be added to the Packages menu.
The submenus are ..
List Projects
Save Project
Edit Project
Edit Projects
Update ProjectsIf you choose the submenu "Edit Projects" this opens a configuration file where paths to different projects can be defined. The path to this file is
/home/username/.atom/projects.csonThis gives you the project management framework to create folders and files for one or more projects.
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Next we add Packages for using markdown. We use the same procedure as above.
apm install markdown-preview-enhanced
apm install markdown-writer
apm install markdown-footnote
And after installation .. again .. Window:Reload (n.b. not Windows)
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You might create a new project folder named "test" to experiment with features.
In project folder "test" (seen in left navigation panel) you can create a new file .. example.md
At the top of every markdown file a metadata block is inserted. Follow the markdown syntax guide.
A basic block might be for starters ..
---
title: 'Integrate Atom with Scribus'
author: 'jack_cat'
date: '26th August 2018'
---
Now you can experiment with the basics of markdown syntax.
Refer to markdown guide.
The key package to enable (after you have installed it) is Markdown Preview Enhanced.
Look at topbar Packages > Markdown Preview Enhanced > Toggle
and you will see a content preview window in right pane.
Any content you insert into your markdown file will be seen in the Preview pane.
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To go to the completion, in the Preview window right click on the content and you will see
Open in Browser
HTML
Chrome (Puppeteer)
PhantomJS
PDF (prince)
eBook
Pandoc
Save as Markdown
Image Helper
Sync Source
You can start with “Open in Browser” but later you can try the advanced features available in Pandoc (more on that later). You can output to web or to Scribus. Pass over the other options while you are learning.
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To avoid composing large documents you can structure your document into a tree structure in Project Manager.
test >
merge.md (concatenating the assets below using @import)
sections>
section01.md
section02.md
section03.md
section04.md
images>
image01.jpeg
image02.jpeg
image03.jpeg
image04.jpeg
vectors>
image01.svg
image02.svg
image03.svg
image04.svg
Now in merge.md you can concatenate content (text and images) by using a series of @import commands embedded in merge.md.
@import "/sections/section01.md"
@import "/images/image01.jpeg"
@import "/sections/section02.md"
@import "/images/image02.jpeg"
Note that sections might also contain @import commands so you can build a tree structure of imports. In merge.md you can for test purposes also comment out entire blocks of @import commands (wrapped in HTML comments tags .. <!-- ... -->) so that they are not concatenated and reduce processing/memory load while previewing.
<!--
@import "/sections/section02.md"
@import "/images/image02.jpeg"
-->
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Turning now to the topic of this thread you wll have installed the package Markdown Footnote.
https://atom.io/packages/markdown-footnoteYou will find different approaches from different developers but this is a good start.
At any point in a section of the main markdown document apply the hotkeys [Ctrl + Shift + B] or use the package menu.
This inserts a footnote and the references are seen in the Preview page.
Note that link and notes are seen in same page. You require all footnotes to be concatenated at the end of your book but we will address that later.
This should give you enough to get started. The final stages will address pushing the previewed content into Scribus.