Change color title of group container widget independently #2743

[Mathis-Hu]

Change color title of group container widget independently.
see issue #2743.

If this pull request is merged, I'll implement the same behavior in DBWR.

[kasemir]

For the group widget, you add a line color to support separate foreground, background and line colors.
Since there's also a change in how they are used for texts vs. lines, GroupWidget#configureFromXML handles the mapping from older versions that don't have the line color to the new one. The GroupRepresentation should then simply use those 3 colors: Line always uses the line color, text uses foreground and background.

Instead, the group widget now has another old_colors flag to tell the presentation how to use them? Can't you remove that by simply setting foreground, background and line colors as desired in configureFromXML?

There are some nonfunctional changes in the formula autocomplete that are unrelated...

[Mathis-Hu]

@kasemir I change the value of the colors directly in the GroupWidget#configureFromXML method as you asked (if I understand it well), I agree it's better that way. Thanks for your feedback. Do not hesitate to give more.

Sorry for the unrelated commit, I still have some struggle with GitHub for chosing some commits and not others.

[kasemir]

That looks good: Widget has new 'line color', and representation simply uses line color for line, fore/back colors for text.

The conversion from older versions is handled in configureFromXML, which sets the new line color from the old foreground, for "TITLE" mode the background becomes the foreground etc.

It's possible that this conversion needs to be tweaked as we open a bunch of older displays and find that we missed something, but that would then be a follow-up update.