[Development] QML and JavaScript extensions

Alan Alpert 416365416c at gmail.com
Sat Nov 16 00:07:41 CET 2013

On Fri, Nov 15, 2013 at 1:58 PM, Richard Moore <rich at kde.org> wrote:
> On 15 November 2013 19:51, Alan Alpert <416365416c at gmail.com> wrote:
>> On Fri, Nov 15, 2013 at 2:00 AM, Kevin Krammer <kevin.krammer at kdab.com> wrote:
>>> On Thursday, 2013-11-14, 21:20:25, Topi Mäenpää wrote:
>>> I also wouldn't consider widgets to be deprecated, at least not yet. And
>>> nicely use QML with widgets as the UI elements, it is not replacing one with
>>> the other either (though you probably meant QtQuick when you wrote QML there).
>> Yeah, QML doesn't deprecate widgets - it deprecates .ui files because
>> now you can construct your widget UIs in QML :D . Long ago we
>> discussed deprecating widgets because Nokia wanted to reallocate those
>> development resources to QML/QtQuick, but thankfully open governance
>> swooped in and saved the day.
> The idea that QML deprecates ui files is frankly utter rubbish. UI
> files offer many advantages over QML - decent widgets, keyboard
> navigation, stability, faster coding for the common case in non-mobile
> applications (to name just a few of them).

You've lost me. I thought the set of widgets available in QML was the
same as in .ui files - all of them. I also didn't know that XML had
better keyboard navigation than QML, but maybe that's because I use
vim for both?

The .ui format is an XML based file format, QML is our own language
that's more readable than XML. When I say QML deprecates .ui files, I
mean that the QML-based format is better for defining your Qt GUIs
than the XML-based format and it's what our tools are starting to use.
Irrespective of whether you are using QtWidgets or QtQuick,
irrespective of whether you created it in designer/creator or by hand.

If you meant "QtQuick doesn't deprecate QtWidgets", then you're
correct (and we already covered that side more than enough). But
please be more careful with your terminology. QML, at least in Qt 5,
is conceptually distinct from QtQuick even though they make an awesome
pair. .ui files might also be miffed at being mixed up with the
widgets you typically use inside them ;) .

> There's nothing wrong with
> QML, there's also nothing wrong with UI files, they just serve
> different use cases.

QML was originally commissioned to replace .ui files. We over-reached
our mandate for sure, but we haven't lost sight of it ;) .

Alan Alpert

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