[Qt-interest] boost types in methods called from QtScript

[Florian Vichot]

Hi RZ,

My guess is that, sadly, there is little you can do appart from changing
your prototype from "uint32" to "uint" or "quint32". This is because
when you call a method of your class from QtScript, Qt looks up the
method in its list of slots and methods marked Q_INVOKABLE, and tries to
find one with the same prototype. Problem is, when you have a method
with a prototype of :

SetStartParameters(uint32 a, uint16 b)

Qt knows nothing of "uint32" and "uint16", and thus when it does a
lookup, it doesn't know if the number it got from QtScript (here 'i')
can be converted into a 'uint32'. It knows it can convert to "quint16",
"quint32", "double", "uint", "int" and a bunch of others, but that's
because the conversion relationships are hardcoded into qvariant.cpp in
Qt's source code.

In your case, from Qt's point of view, "uint32" could be anything, even
a non POD type. So it doesn't take chances, and deems the types are
incompatible, hence the TypeError.

Florian


RZ a écrit :
> Hello all,
> 
> I managed to get my C++ (QObject derived) class invokable from QtScript. 
> So I can do in QtScript:
> 
> var myClass = new MyClass();
> 
> Unfortunately this C++ base class uses boost::uint32_t, boost::uint16_t, 
> ... (and then typedef boost::uint32_t uint32, ..). So a method inside my 
> class is:
> 
> SetStartParameters(uint32 a, uint16 b)
> 
> I can do
> 
> myClass.SetStartParameters(1, 2);
> 
> but whatever I try if I want to use var's instead like
> 
> var i = 2;
> myClass.SetStartParameters(1, i);
> 
> I always get a "TypeError" (because i is no uint16); interestingly it 
> works if I construct an overloaded method using Qt's types
> 
> SetStartParameters(quint32 a, quint16 b);
> 
> I tried things like Q_DECLARE_METATYPE(uint32), 
> qRegisterMetaType<uint32>("uint32"), qScriptRegisterMetaType (where I 
> don't know if I passed all parameters correctly).
> 
> Can anybody help what to do to get uint32 to work?
> 
> Thx,
> 
> RZ
> 
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