[Interest] What's the recommended way to put QObjects in smart pointers?

[Sean Harmer]

On Wednesday 04 May 2016 17:48:50 Nikos Chantziaras wrote:
> I've been removing every trance of 'new' and 'delete' from my code and
> switching to something like:
> 
>    auto obj = std::make_unique<Type>(ctor args);
> 
> (Or std::make_shared, depending on the situation.)
> 
> But for QObjects with a parent, that can go horribly wrong. So I have to
> do annoying stuff like:
> 
>    auto dialog = new QDialog(parent);
>    // work...
>    delete dialog;
> 
> Yes, 'parent' will eventually delete 'dialog', but that doesn't help
> much when 'parent' is a long lived object (like the main application
> window.)
> 
> Is there a Qt-specific idiom where I can manage QObjects that have a
> parent with a smart pointer and not have to worry about double-deletion?
> 
> Or, to phrase it in another way, is there a way to eliminate the 'new'
> keyword completely from my code-base when using QObjects with a parent?

Use smart pointers to only manage the root objects of your QObject hierarchies 
and rely upon QObject to manage the child objects.

Cheers,

Sean
-- 
Dr Sean Harmer | sean.harmer at kdab.com | Managing Director UK
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