Thiago, can you please elaborate how you see this? For a simple TreeItem a pair of std::unique_ptr/std::observer_ptr should be enough (with a bunch of convenience methods to insert children):
struct TreeItem { observer_ptr<TreeItem> parent; vector<unique_ptr<TreeItem>> children; }; Yes, the code becomes a bit verbose, but the ownership transfer is now visible with those (ugly) std::moves. I can think of an alternative of using shared pointers (since we already have a QPointer aka WeakPointer<QObject>) but I think it gives too much overhead just to support corner cases. If QLayout::addWidget() will return an observer_ptr*, you can just do auto button = layout->addWidget(make_unique<QPushButton>(«RIGHT»)); button->setFlat(true); * ok, you need a template version of addWidget for that, but since c++ is all about templates these days it doesn’t really a disadvantage > 3 мая 2019 г., в 20:24, Thiago Macieira <thiago.macie...@intel.com> > написал(а): > > On Friday, 3 May 2019 10:22:20 PDT Daniel Teske wrote: >> std::unique_ptr<QPushButton> rightButton = >> std::make_unique<QPushButton>("RIGHT"); >> layout->addWidget(std::move(rightButton)); > > The problem in this particular example is that once you've added the widget, > the rightButton smart pointer no longer has a pointer. You can't continue to > set up your push button. In most cases, this is just a matter of moving the > set up before the addition / reparenting, or using the other idiom where the > object is never in a smart pointer in the first place. > > So this begs the question of whether std::unique_ptr is the best smart > pointer > for this scenario. Would it make sense to create one that understands parent- > child relationship? > > -- > Thiago Macieira - thiago.macieira (AT) intel.com > Software Architect - Intel System Software Products > > > > _______________________________________________ > Development mailing list > Development@qt-project.org > https://lists.qt-project.org/listinfo/development _______________________________________________ Development mailing list Development@qt-project.org https://lists.qt-project.org/listinfo/development