Allow setBackgroundColor() to change the alpha-level.
Currently, setting an alpha-level with
setBackgroundColor() does not have any effect.
For instance, the following code:
container->decorationStyle().setBackgroundColor(Wt::WColor(255, 0, 0, 128));
Produces a container with its color defined in
rgb() instead of
<div id="o3knw4h" style="background-color:rgb(255,0,0);"></div>
This isn't really a bug since this has always been the case.
It is possible to change the alpha-level using CSS, and I guess that's what most people have been using.
Forum topic related to the issue: Can't set alpha-level of WContainerWidget