On Wednesday 12. March 2014 12.48.20 Olivier Goffart wrote: > On Monday 10 March 2014 17:43:35 Giuseppe D'Angelo wrote: > > Can you please explain what this feature is about, why do you think > > it's useful, how it's supposed to be used, etc.? > > > > On 10 March 2014 17:30, mikhail.svet...@gmail.com > > > > <mikhail.svet...@gmail.com> wrote: > > > Hello, I would like to clarify wherein the complexity > > > (https://codereview.qt-project.org/#change,80412)? > > > Ready to listen to any suggestions and implement them. > > This is a follow-up on the earlier discussion: > "About Q_PROPERTY in custom widget plugin for designer" > > Svetkin's first idea was to extend the READ and WRITE attributes to be more > complex expressions such as: > > Q_PROPERTY(QString label READ ui->customWidget->label > WRITE ui->customWidget->setLabel) > > And he even made a patch for it: (https://codereview.qt-project.org/77758) > There was small issues with the patch. Notably on how complex can the > expression be, and also on the fact that it would still be hard to have a > NOTIFY signal. > > I was also wondering if it would not be better to copy QML's idea of > property aliases: > > Q_PROPERTY(QString label ALIAS CustomWidget ui->customWidget->label) > > However, now that Svetkin proposed a patch, I feel that it is not so much of > a good idea. I think the syntax is not so nice especially the need to have > both the class name and the 'path' to the property. And also because the > notify signal is still not automatic. > > And overall, i find myself preferring the first idea better. Hence I would > like more opinions from the list. > > The other question is if we should have that at all. How common is it to > have property alias like this?
I'm also not sure if it's worth it. Perhaps using Q_PRIVATE_PROPERTY gets us close enough? My worry would be that it has to work together with QML, which requires an API to resolve aliases at run-time, in order to install bindings on the _real_ property and not the alias (and therefore also remove a previously installed binding). The alias implementation QML goes through quite some lengths to achieve that and the automatic connect to the notify signal. Simon _______________________________________________ Development mailing list Development@qt-project.org http://lists.qt-project.org/mailman/listinfo/development
