Qt ActiveX dynamicCall: bad parameter count

Question

I am trying to use an ActiveX control in my program.

QAxWidget* mAX = new QAxWidget();
mAX->setControl("{XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX}");

I know that there is a function:

put_ChannelType(long newValue)

But when I try to execute it:

mAX->dynamicCall("put_ChannelType(long)",2);
mAX->dynamicCall("put_ChannelType(int)",2);
mAX->dynamicCall("put_ChannelType(long)",QVariant(2));
mAX->dynamicCall("put_ChannelType(int)",QVariant(2));

I get:

QAxBase: Error calling IDispatch member put_ChannelType: Bad parameter count

Any idea what is going wrong ?

EDIT:

Weird thing is if I call

mAX->dynamicCall("put_ChannelType()");

I do not get any error message...

EDIT 2:

This also fails (as Constantin suggested)

QList<QVariant> varlist;
varlist << (int)1;
mAX->dynamicCall("put_ChannelType(int)",varlist);

I got this error when calling events/slots from different threads incorrectly. Are you using QThreads? — Constantin, Feb 13 '13 at 18:06
http://qt-project.org/forums/viewthread/4842 Maybe, pass in a `QList vars` instead? — Constantin, Feb 13 '13 at 18:32

score 1 · Accepted Answer · answered Feb 14 '13 at 19:30

Got this solved using the generateDocumentation() function.

I was using this ActiveX control in another application, but an MFC one.

It seems the function names I was referring to (which were in a machine generated IDispatch wrapper class created by VS) were not the same as the ones Qt listed.

i.e. put_ChannelType is actually SetChannelType...

Maybe this is just a version issue ?

Anyways, important part is knowing that generateDocumentation() can list you all the functions you can call with dynamicCall.

score 0 · Answer 2 · answered Feb 15 '13 at 01:51

0

Is it OK? mAX->dynamicCall("put_ChannelType(const QVariant &)", (long)2);

answered Feb 15 '13 at 01:51

idobatter

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Qt ActiveX dynamicCall: bad parameter count

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