[Interest] moveToThread used in constructor to move "this"

[André Somers]

Op 24/02/2016 om 09:39 schreef Lorenz Haas:
> Hi,
>
> keep calm, it is not about moveToThread(this) :)
>
> One canonical way to use QObjects and QThreads is this
>
> void SomeClass::init() {
>      // m_thread is a member of SomeClass
>      Foo *foo = new Foo; // Foo inherits QObject
>      foo->moveToThread(&m_thread);
> }
>
> So in my case I want that an instance of Foo is always moved to a
> (single) thread. In order to take this knowledge/requirement - as well
> as the boilerplate code - from the caller (here SomeClass::init) I am
> curious if this is would be a valid substitution:
>
> Foo::Foo() : QObject(nullptr) {
>      // m_thread is now a member of Foo
>      moveToThread(&m_thread);
> }
>
> void SomeClass::init() {
>      Foo *foo = new Foo;
> }
>
>
> I guess that in the constructor of Foo the base class QObject is
> already instantiated and since moveToThread only has implications on
> QObject it should be right.
> Can any one with deeper QThread insight confirm that using
> moveToThread in a constructor like above is safe?
>
That should work just fine, with the exception of using &m_thread as a 
member. If you want to use the class as you write it above, then there 
is no way to set that member. You will probably need to use some form of 
a static here, either inside the class itself if you don't need control 
over the actual thread creation itself, or externally, perhaps wrapped 
in some kind of singleton.

André