[Interest] How to get instance of qml singleton on C++ side

[Pierre-Yves Siret]

You could do an usual c++ singleton

Foo& Foo::instance()
{
    static Foo foo;
    return foo;
}

And use that in c++ and also in the singleton provider for QML :

qmlRegisterSingletonType<Foo>("com.example", 1, 0, "Foo", &Foo::create);

QObject* Foo::create(QQmlEngine*, QJSEngine*)
{
    Foo* foo = &instance();
    QQmlEngine::setObjectOwnership(foo, QQmlEngine::CppOwnership);
  return foo;
}

2018-01-15 7:35 GMT+01:00 Лагнер, Сергей <developer at lagner.ru>:

> Hi
>
> It's exactly what I need.
> I thought about such solution but compile new component,
> create instance of it... seems like huge amount of extra work.
> And it is kind of tricky. I was hoping the other way exists.
>
> But thank you anyway.
>
> 2018-01-14 16:41 GMT+07:00 Ben Lau <xbenlau at gmail.com>:
>
>>
>> You may take this piece of code as an example:
>>
>> https://github.com/benlau/quickflux/blob/master/qfappdispatcher.cpp#L51
>>
>> On 14 January 2018 at 17:09, Лагнер, Сергей <developer at lagner.ru> wrote:
>>
>>> Hello all.
>>> I have two classes registered as qml singletons.
>>>
>>>
>>> QObject * First::create(QQmlEngine*, QJSEngine*) {
>>> return new First();
>>> }
>>>
>>> QObject * Second::create(QQmlEngine*, QJSEngine*) {
>>> return new Second();
>>> }
>>>
>>> qmlRegisterSingletonType<First>("com.example", 1, 0, "First",
>>> &First::create);
>>> qmlRegisterSingletonType<Second>("com.example", 1, 0, "Second",
>>> &Second::create);
>>>
>>>
>>>
>>> Now I'd like to have an access to one of them from another.
>>> For example
>>>
>>> void Second::method() {
>>> // I need First * instance here
>>> }
>>>
>>> Is there any way to get qml singleton instance on C++ side, from
>>> QQmlEngine or something?
>>>
>>> ---
>>> Have a nice day.
>>> Sergey
>>>
>>> _______________________________________________
>>> Interest mailing list
>>> Interest at qt-project.org
>>> http://lists.qt-project.org/mailman/listinfo/interest
>>>
>>>
>>
>
> _______________________________________________
> Interest mailing list
> Interest at qt-project.org
> http://lists.qt-project.org/mailman/listinfo/interest
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.qt-project.org/pipermail/interest/attachments/20180115/0ab18551/attachment.html>