Using constructor with WrapperFactory

[Sergey]

Hello!
I master PythonQt by means of examples, use Qt SDK 1.1 for Windows, PythonQt 2.0.1.
I can not force to work Wrapper Factory in example PyCPPWrapperExample. At execution of a script examle.py the error stands out:

py> 
alternative 1 : CustomObject wrapped by decorators
CustomObject (C++ Object 0x09B92F20)
['__dict__', '__doc__', '__init__', '__module__', '__weakref__', 'className', 'delete', 'firstName', 'help', 'lastName', 'setFirstName', 'setLastName']
Mike Michels
alternative 2 : CustomObject2 wrapped by factory
CustomObject2 (C++ Object 0x09B92FA0)
['__dict__', '__doc__', '__init__', '__module__', '__weakref__', 'className', 'delete', 'help']
Traceback (most recent call last):
  File ":example.py", line 35, in <module>
AttributeError: CustomObject2 has no attribute named 'setFirstName'
py>

If the object is created not by the constructor, and with the slot of auxiliary object, for example, how is made in a test example PythonQtTestSlotCalling::testCppFactory():

  QVERIFY(_helper->runScript("if obj.createPQCppObject(12).getHeight()==12: obj.setPassed();\n"));
  QVERIFY(_helper->runScript("if obj.createPQCppObject(12).getH()==12: obj.setPassed();\n"));
  QVERIFY(_helper->runScript("pq1 = obj.createPQCppObject(12);\n"
    "pq2 = obj.createPQCppObject(13);\n"
    "pq3 = obj.getPQCppObject(pq1);\n"
    "pq4 = obj.getPQCppObject(pq2);\n"
    "if pq3.getHeight()==12 and pq4.getHeight()==13: obj.setPassed();\n"
    ));

it works. But all the same, the object created by the constructor, doesn't use WrapperFactory.
What do I don't understand?

Yours faithfully,
Sergey.

[Florian Link]

Hi Sergey,

the wrapper factory approach is quite old and nowadays we typically use decorators.
I updated to examples shortly after the 2.0.1 release, maybe testing the SVN trunk version fixes the problem?

On the otherhand, I am not sure if constructors ever worked together with wrapper factories, I would use decorator classes instead! Another workaround is to use a factory method instead of a constructor (just a slot that returns the new object, this can even be a static decorator, so that it is a factory method on the class)

regards,
Florian

regards,
Florian

[Sergey]

Hello, Florian!
Thanks for the help! I will try your councils, of course.

I will explain, why I use the Factory approach. I need to wrap up mine C++ classes which have been not QObject derived. Thus I want to use Qt properties that in python scripts to write so: obj.attr = value. And even so: obj.subobj.attr = value.
The slots of decorators need to pass a pointer to the wrapped object as the first argument. Hence, in the decorators I can not realize property Qt. Or I am mistaken?

Yours faithfully,
Sergey.

[Florian Link]

Hi Sergey,

that is true. But you can emulate properties in the decorators like this:

public slots:
  void py_set_yourProperty(YourClass* cpp, YourTypeOrQVariant value) { … }
  YourTypeOrQVariant py_get_yourProperty(YourClass* cpp) { … }

This will add a python property named yourProperty to your wrapped C++ class.
You can either use concrete types or QVariant for the value of the property.

regards,
Florian

[Sergey]

Many thanks! I will try.

Yours faithfully,
Sergey.

[Sergey]

It works! It is documentary feature?
Yours faithfully,
Sergey.

[Florian Link]

No, I actually forgot to document it, since I added it mainly for QStyleOption public member wrapping done by the code generator.

[Sergey]

In my opinion, it is very useful feature. It saves the whole line of a code on each property! It is necessary to document it, that there was a confidence that in the future it will be supported.
Thanks for library! Successes!
Yours faithfully,
Sergey.