How to invoke method by function pointer?

Question

Invoking a method

Normal way :

QMetaObject::invokeMethod(obj, "function");

But instead of using string.This is what I want :

QMetaObject::invokeMethod(obj, function());
// or any macro like SLOT
QMetaObject::invokeMethod(obj, FUNC_NAME(function()));

Why using `QMetaObject::invokeMethod` istead of directly call the method by `obj.func()`? — putu, Jun 14 '17 at 04:26
Specifically, in [this answer](https://stackoverflow.com/a/21653558/1329652) look for the "TL;DR for methods/slots" — Kuba hasn't forgotten Monica, Jun 14 '17 at 13:50

score 0 · Answer 1 · answered Jun 14 '17 at 07:06

0

I strongly recommend you to use the normal way, i.e. using QMetaObject::invokeMethod(obj, "function"). However, if you want you can use the following stringify macro:

#define FUNC_NAME(a)         (QString(#a).remove(QRegExp("\\((.*)\\)")).trimmed().toLatin1().constData())

//usage
QMetaObject::invokeMethod(obj, FUNC_NAME(function()));

The above macro convert argument to string then remove method/function arguments between (...).

answered Jun 14 '17 at 07:06

putu

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The stringify macro provides no compile-time protection against a change in the function signature, unlike the Qt 5.10 function pointer syntax overloads which result in compiler errors if the function name does not exist. – pixelgrease Nov 03 '18 at 20:19

How to invoke method by function pointer?

1 Answers1