[Sketcher] Make constraint label smaller and styleable

[chennes]

As discussed in the FreeCAD forums, this PR exposes the Sketcher Constraint Status Label to user-configurable styling via both preferences (no GUI, just settable in user.cfg) and via the Qt stylesheet. This is accomplished by creating a new widget called StatefulLabel. This widget has a Q_PROPERTY called "state" which can be dynamically altered at runtime. When the state is changed, the user preferences are optionally scanned for an entry as specified by the label creation code, then the stylesheet is checked, and finally, the default values are used as a fallback.

This PR also significantly reduces the verbosity of the message, eliminates the possibility of multiple overlapping messages (e.g. "redundant" and also "partially redundant"), and moves the clickable portion of the label to its own UrlLabel (which can be styled, unlike an embedded <a> element).

[freecadci]

for feature branch PR_5091. Pipeline #383250984 was triggered at 4154bdd. All CI branch pipelines.

[freecadci]

for feature branch PR_5091. Pipeline #383771254 was triggered at 6858d93. All CI branch pipelines.

[freecadci]

for feature branch PR_5091. Pipeline #383431392 was triggered at 4154bdd. All CI branch pipelines.

[freecadci]

for feature branch PR_5091. Pipeline #383839759 was triggered at 6858d93. All CI branch pipelines.

[abdullahtahiriyo]

@chennes

It is conflicted, could you please resolve the conflict?

[chennes]

Yes, I caused the conflict 😄 -- I'll take care of it.

[freecadci]

for feature branch PR_5091. Pipeline #386440259 was triggered at 6bcda71. All CI branch pipelines.

[abdullahtahiriyo]

CI is complaining about an unused parameter:

../../../src/Gui/Widgets.cpp: In member function 'virtual void Gui::StatefulLabel::OnChange(Base::Subject<const char*>&, const char*)':
../../../src/Gui/Widgets.cpp:935:58: warning: unused parameter 'rCaller' [-Wunused-parameter]
  935 | void StatefulLabel::OnChange(Base::Subject<const char*>& rCaller, const char* rcReason)
      |                              ~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~
make[2]: *** [src/Gui/CMakeFiles/FreeCADGui.dir/build.make:4658: src/Gui/CMakeFiles/FreeCADGui.dir/Widgets.cpp.o] Error 1
make[1]: *** [CMakeFiles/Makefile2:6872: src/Gui/CMakeFiles/FreeCADGui.dir/all] Error 2
make: *** [Makefile:130: all] Error 2
Cleaning up project directory and file based variables
ERROR: Job failed: exit code 1

[berndhahnebach]

Just restared the job and it really fails on 6bcda71

[abdullahtahiriyo]

@chennes
No rush. Just making sure you get notified.

[chennes]

Thanks, @abdullahtahiriyo -- I think I have resolved the issue (this time I tested on Linux!). I've also added a commit to include basic styling of the label in all of our included stylesheets. I used the coloring you originally had in the code, except to switch black text to white on the dark styles, and to make the URL a lighter color on the dark styles. I figure folks like @turn211 will want to go back in and tweak those colors for better visibility, but this is a good starting place.

[abdullahtahiriyo]

@berndhahnebach
Do you know if we need to retrigger the gitlab pipeline somehow after the new commits?

If yes, if it is something we can do (without having to disturb you), please let us know how to do it. :)

[freecadci]

for feature branch PR_5091. Pipeline #387344400 was triggered at dc3583e. All CI branch pipelines.

[abdullahtahiriyo]

@chennes
For reasons I cannot understand the button "Rebase and Merge" is present but cannot be clicked. I tried login out and back in in GitHub.

I have clicked "update branch", although this is something that was never needed to do a "rebase and merge". This has triggered a new gitlab pipeline check.

I will try later on during the day. If I can not, I suggest you merge it, as I have reviewed the changes and tested it and I am satisfied.

[abdullahtahiriyo]

I am trying to unveil the reason why I cannot merge this PR. So I requested another review from myself, which I am approving now.

[abdullahtahiriyo]

@chennes

Very odd. I can rebase and merge my own PR:
#5109

which has not passed the tests (this is something we could do before, i.e. merge without passing the tests)

But I could not rebase and merge this one, when it had passed the tests (before hitting update)...

[abdullahtahiriyo]

@berndhahnebach

Sorry to disturb you again. I cannot make CI run the last commit in this thread.

In the GitLab UI I can re-trigger previous pipelines...

[abdullahtahiriyo]

At the end, the issue appears to be that the PR could not be "rebased and merged" (which is what I usually do to have cleaner history). I have now "created a merge commit". Thanks for your support.