Sqitch GUI development

I’m experimenting with a project to make a GUI for the excellent Sqitch database change management application. I started the project some time ago, and because lately it got some attention from the author of Sqitch - David E. Wheeler, I was stimulated to continue working on it.

Sqitch was first written in Perl Moose as initially was my Sqitch GUI interface, but it was rewritten in Moo lately.

David suggested that I should also use Moo, so now as I write this, all the GUI parts use Moo already (in the devel branch), and works quite nicely with the exception of the wxPerl Menu component.

The translation to Moo was quite easy because Moo and Moose are compatible, but involved heavy usage of my Emacs editor. One of the tricky parts was with the type system, but that was already solved by David and I could easily adapt the Type module from Sqitch. The other tricky part was making Moo and wxPerl understand each other. For the Moose version I used the MooseX::NonMoose::InsideOut module and while switching to Moo I experimented with the MooX::InsideOut module.

All was working well until I was rewriting a bigger part of the application when I started getting errors like:

Can't use string (""menu_app"") as a SCALAR ref while "strict refs" in use at .../lib/Method/Generate/Accessor/Role/InsideOut.pm line 21.

While looking on the Net for a solutions it turned out that it doesn’t even need the MooX::InsideOut module, Moo already has a FOREIGNBUILDARGS method, thanks to tobyink for the enlightening response on stackowerflow.

After removing the module, the error changed to:

Can't locate object method "menu_app" via package "Wx::MenuBar" at lib/App/Sqitch/GUI/View/MenuBar.pm line 66.

This looks more familiar, but there is a menu_app method in the App::Sqitch::GUI::View::MenuBar package, what’s going on? I managed to reproduce the error with a script, but it took some time until I realized where is the problem, the via package should be App::Sqitch::GUI::View::MenuBar not Wx::MenuBar. The solution of the problem was, again, unexpected, there is no real need to subclass Wx::MenuBar. See my question and the answers on PerlMonks, for details, if interested.

Here is a screen-shot of the application with it’s current look:


  • Simplified projects dialog;
  • Add syntax highlighting to the log widget;
  • Started switching to Moo;
  • Hopefully an improved API;