Implement Dynamic Legend

[clhenrick]

The legend should change based on whether the user has selected "trend" or "compare".

Circles for "compare" should be displayed while lines for "trend" should be displayed.

To Consider:

• Should the compare legend update in response to the user toggling crash types? For example if fatalities aren't selected then should filled in circles for fatalities display?

• Should a user be able to deselect a geo from the legend when viewing "compare"? Might make sense to be consistent with that functionality between the trend and compare views.

[danrademacher]

Good question re legend items and filter.

My first thought is that this legend is short enough and clear enough that it's better to leave it static rather than filtering legend items based on applied filters. Having them all there makes the "system" immediately evident, even if someone sends you a link that's filtered.

Though in that case we need to be sure it's clear filters are active so you don't misread the chart as "no fatalities" if the fatalities are merely filtered out.

[clhenrick]

@danrademacher perhaps it then makes sense to remove the "deselect" option from the Trend View? Seems inconsistent to make the Legend interactive in one view but not the other.

[danrademacher]

Or maybe instead of element disappearing, it just grays out or otherwise shows as deselected?

[clhenrick]

Not sure I'm following.