Re: [platform-swt-dev] SWT enhancements

[Aleksandar Kurtakov <akurtako@xxxxxxxxxx>]

----- Original Message -----
> From: "Stefan Winkler" <stefan@xxxxxxxxxxxxxx>
> To: platform-swt-dev@xxxxxxxxxxx
> Sent: Sunday, August 3, 2014 3:13:12 PM
> Subject: [platform-swt-dev] SWT enhancements
> 
> Hi,

Hi, 
sorry for long wait time - traveling, vacations, etc. and mails get easily missed in this period.

> 
> for those, who don't know me: I am Stefan, you might have met me (or not ...)
> on a few EclipseCons in the past mainly talking about EMF.CDO stuff. A few
> months ago I dived a bit into Platform.UI, related to the dark theme and CSS
> engine.
> 
> Why I am actually writing this message: I'd like to see a few features in SWT
> which are not there, yet.
> 
> For example, to make the dark theme more usable, there is Platform Bug 440247
> which basically states that we should be able to set (override) the
> *org.eclipse.swt.SWT.COLOR_INFO_BACKGROUND* and
> *org.eclipse.swt.SWT.COLOR_INFO_FOREGROUND* constants from CSS.
> That however, seems impossible to me on Platform.UI level. What is needed is
> a Display.setSystemColor() method.

I have some concerns about allowing to set new values for things defined in the underlying toolkit theme. Thanks to improper usage of such values we end up with white on white or black on black cases with various themes (esp. with gtk the variety is way too big). But I'm always in favor of people coming with smth for them and reiterating on top of that to fix some of the constraints as usually we get better discussion when diving into the code.

> 
> Then, there are Bug 419377 and Bug 430208 which call for CSS support for
> transparency (or even semi-transparency) and a CSS 'inherit' property. Those
> are hard, or even impossible to implement in the CSS engine without suitable
> support in SWT.

It was mentioned in multiple discussions already that an API like setStyle(some_css) might be really nice addition to SWT at least from GTK POV it shouldn't be a big problem, it would even be the preferred way as the current way of setting colors/foreground/background is deprecated so exposing it even more instead of the preferred css-way seems wrong to me. But such a change will require dedicated person to look into the 3 supported UI toolkits - Cocoa, GTK and Win32 and check what's possible with all of them. There would be added benefit of not having platform.ui to understand the css as it can be delegated to the underlying toolkit.

> 
> So my question is: Can I open Bugs against SWT and just try to start
> contributing enhancements? Or should these be discussed here (or somewhere
> else) first? Or is SWT considered to be too 'finished' to add such features?

Always best to start a discussion with some proof of concept code in my eyes, things can always be bringed to mailing list or some other discussion if the change is too big or questionable or whatever else.

> 
> Also, if I start contributing, how do I do it? (I have read
> https://www.eclipse.org/swt/fixbugs.php and cloned the SWT repository, I
> know how to use Gerrit etc. but what else - more SWT-specific - is there to
> know?)
> As there is no declared (platform-independent) interface for SWT classes, I
> could pretty much break compatibility, if I don't add the same method to all
> platforms, right? Is there a test mechanism that validates and cross-checks
> the platform-dependent bundles for compatibility?

Good question, I never spent time checking that but honestly all active swt committers have their hands full with so many bugs that none of us seems to even have the time to think about adding new features.

Looking forward for your contributions,
Alexander Kurtakov
Red Hat Eclipse team

> 
> Best,
> Stefan
> 
> 
> _______________________________________________
> platform-swt-dev mailing list
> platform-swt-dev@xxxxxxxxxxx
> To change your delivery options, retrieve your password, or unsubscribe from
> this list, visit
> https://dev.eclipse.org/mailman/listinfo/platform-swt-dev