[Interest] Pointers as Q_PPOPERTY

[Sandro Andrade]

On Sat, Nov 2, 2013 at 5:31 PM, Sandro Andrade <sandroandrade at kde.org> wrote:
> On Mon, Oct 28, 2013 at 8:13 AM, Stephen Kelly <stephen.kelly at kdab.com> wrote:
>> On Monday, October 07, 2013 09:55:53 Sandro Andrade wrote:
>>> On Wed, Oct 2, 2013 at 11:18 AM, Stephen Kelly <stephen.kelly at kdab.com>
>> wrote:
>>> > On Wednesday, October 02, 2013 19:02:54 Дмитрий Козлов wrote:
>>> >> Q_PROPERTY(Hull * hull READ hull)
>>> >> Q_PROPERTY(Reactor * reactor READ reactor)
>>> >> Q_PROPERTY(Shields * shields READ shields)
>>> >>
>>> >> This approach should work in your case.
>>> >
>>> > This will work with QML with Qt 5.2.
>>> >
>>> >  https://codereview.qt-project.org/#change,42703
>>> >
>>> > Before that, your Q_PROPERTY needs to be type QObject*.
>>>
>>> That's great. What about QList<NonQObject *> ? Do I still need to use
>>> QQmlListProperty in Qt 5.2 ?
>>
>> Did you try it?
>>
>> I suggest trying to use it with the QVariant API and the QML API.
>
> After digging a little bit about that I've realized that QList<QObject *>-typed
> Q_PROPERTIES are successfully available for use as QML models even in Qt 5.1.1.
>
> QList<QObject-derived *>-typed Q_PROPERTIES cannot be used as models, since
> they aren't automatically converted to a JavaScript array (are rather
> kept as QVariant(QList<QUmlProperty*>), for example).
>
> It seems qmlRegisterType<T> requires T be derived from QObject, so
> qmlRegister'ing QList<QUmlProperty*> isn't a solution.
>
> Luckily, I'm using QList<QObject *> properties but this'd prevent
> things working fine otherwise.
>
> Any hint ?

In addition,

1) QList<QObject *>-typed Q_PROPERTIES can be directly bound as QML models.
2) QList<QObject *>-typed Q_PROPERTIES can be successfully accessed in
QScriptEngine engine, provided qScriptRegister(Sequence)MetaType is
used to register them.
3) QList<QObject *>-typed Q_PROPERTIES cannot be accessed in QML's
JavaScript engine, since they are kept as QVariant(QList<QObject*>).

Since QQmlEngine inherits QJSEngine, which provides no counterpart for
qScriptRegisterMetaType, it is currently possible to register such
custom type in QML's JavaScript engine ? Is QJSEngine intended to
replace QScriptEngine in the future ?

Thanks in advance,
Sandro

>
> Thanks,
> Sandro
>
>>
>> Thanks,
>>
>> --
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>>
>> Stephen Kelly <stephen.kelly at kdab.com> | Software Engineer
>> KDAB (Deutschland) GmbH & Co.KG, a KDAB Group Company
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