Completion calculations can return NaN when page content is optional

[chris-steele]

Subject of the issue/enhancement/features

If a page contains only optional content then calculatePercentageComplete will return NaN because it performs division by zero. This results in the PLP indicator appearing to show 100% completion due to the resulting style --adapt-pagelevelprogress-percentage: NaN%;

Your environment

• latest framework (vanilla theme)

Steps to reproduce

Use "_isOptional":true on all contents of the page (components, blocks and articles).

[oliverfoster]

Probs division by zero error.
Should be:
!total ? 0 : count / total
Rather than
count / total

[oliverfoster]

Both of these need correcting:

adapt-contrib-pageLevelProgress/js/PageLevelProgressIndicatorView.js

Line 60 in 643125b

return Math.round(visited.length / children.length * 100);

adapt-contrib-pageLevelProgress/js/completionCalculations.js

Line 135 in 643125b

const percentageComplete = Math.floor((completed / total) * 100);

Called from:

adapt-contrib-pageLevelProgress/js/PageLevelProgressIndicatorView.js

Lines 43 to 46 in 643125b

	const percentage = this.calculatePercentage();
	this.model.set('percentageComplete', percentage);
	this.$el.css({
	'--adapt-pagelevelprogress-percentage': percentage + '%'

[joe-replin]

Great, thank you. This takes care of the calculation issue. But from a visual standpoint, the progress bar on both menu and page remain empty. That doesn't really represent a fully optional page, would it? I'm open to suggestions but here are some ideas. For fully optional pages, should we....

• Hide the progress bar on the menu and on the navigational bar while within the topic?
• Show the progress bar full?
• Replace the progress bar with a symbol or the words 'Optional content' like we do within the drawer?
• Keep it as an empty progress bar?

[oliverfoster]

My preference is to add an "Optional" label and keep the progress bar. (At the time of implementation, with drawer, having both progress and an optional label appeared to take up too much space, however, I'm happy for that to be corrected.)

My rational is the optional/mandatory and completion-progress are different dimensions of the same object.

See adaptlearning/adapt_framework#3557

As can been seen from the above previous attempt at solving it, there has been no additional design input or acknowledgement around and of the essential elements as documented. My suggestion is to keep those indicator dimensions as clearly differentiated and uniform as possible, as they are all organic and distinct.

[github-actions]

🎉 This issue has been resolved in version 8.3.3 🎉

The release is available on GitHub release

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