How can you change the colour of the R background for `exams2moodle` questions?

Question

I'm writing some quizzes for Moodle using R/exams' exams2moodle. The XML file is created fine and I can import the quiz to Moodle ok, however, any question that has R code as part of either the question or the solution has the R code on a dark background making it almost impossible to read. Is there an option somewhere that controls this?

I am using this code to create the XML:

exams2moodle(c("q1.Rmd", "q2b.Rmd", "q3.Rmd", "q4.Rmd", "q5.Rmd", "q6.Rmd"), 
             name = "GLM_prac1", 
             iname = FALSE,
             converter = "pandoc-mathjax",
             cloze = list(cloze_schoice_display = "MULTICHOICE_V"))

And this is an example of the issue:

Answer 1

The color of the R code displayed is not controlled through exams2moodle(), at least not explicitly. What exams2moodle() does, is to put verbatim code input and output into standard HTML tags for this <pre><code> ... </code></pre>. This stands for pre-formatted text with markup for typewriter code. (Actually, this is not even produced by exams2moodle() directly but by pandoc.)

The rendering of these standard HTML tags is then controlled through the CSS styles employed in your Moodle installation. In a vanilla Moodle installation you currently simply get a black font on the same light blueish background as for regular text. In previous versions the background was light gray. Given that you have light orange background for text and dark background for code, I guess that this is a setting in your Moodle installation. Hence I would recommend to reach out to the Moodle team at your university and ask them about this. This seems to be a poor setting that would likely affect others as well.

If you cannot get in touch with the Moodle team or they are unwilling to change their CSS, you can insert your own custom CSS code into your exercises. The advantage is that you have full control over the color then. The disadvantage is that you yourself have to include that style code into every exercise where it is needed. It is not hard but tedious. For example, you can include the following R code chunk in the exercise directly at the beginning of the question section:

Question
========

```{r, echo = FALSE, results = "asis"}
writeLines("<style>
pre {
  background: #FFFFFF00
}
</style>")
```

This simply inserts a short HTML snippet with CSS into your Rmd exercise:

<style>
pre {
  background: #FFFFFF00
}
</style>

This will instruct the browser to use the background color #FFFFFF00 (fully transparent white) for all <pre>-formatted chunks. Of course, you can also play around with this and use a different color, say #EEEEEE (light gray) or similar.