Thank you for the answer above Bergi. Nice one! I will add the entire script modified as per the section. It of course is saved as the header.htm
file pointed to in the index.Rmd
yaml as described by another leader named Sébastien Rochette in his post linked in the question.
It seems that the toggle switch needed to be named as universal (i.e Show/Hide Code
) since the state of each "chapter" of the bookdown doc did not always jive with what the toggle button was displaying when it was hit when reviewing other "chapters"...
<script type="text/javascript">
// toggle visibility of R source blocks in R Markdown output
function toggle_R() {
var x = document.getElementsByClassName('r');
if (x.length == 0) return;
function toggle_vis(o) {
var d = o.style.display;
o.style.display = (d == 'block' || d == '') ? 'none':'block';
}
for (i = 0; i < x.length; i++) {
var y = x[i];
if (y.tagName.toLowerCase() === 'pre') toggle_vis(y);
}
var elem = document.getElementById("myButton1");
if (elem.value === "Show/Hide Code") elem.value = "Show/Hide Code";
else elem.value = "Show/Hide Code";
}
document.write('<input onclick="toggle_R();" type="button" value="Show/Hide Code" id="myButton1" style="position: absolute; top: 10%; right: 2%; z-index: 200"></input>')
document.addEventListener('DOMContentLoaded', toggle_R);
</script>