In KDialogBoxButton::addButton() what is the third argument?

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KPushButton *addButton (const KGuiItem &guiitem, ButtonRole role, QObject *receiver=0, const char *slot=0)

The QObject *receiver=0 part of it.

I'm trying to put in:

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KPushButton *nextButton = addButton(nextGuiItem, AcceptRole, 0, next());

But, I don't know what to put into the third argument.

The third argument is the object that will have the slot specified in argument 4 invoked upon it. I gather you have a slot called next() in the class you are currently in? If so, try the following:

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KPushButton *nextButton = addButton(nextGuiItem, AcceptRole, this, SLOT(next()));

The third argument expects a QObject*, but the class that the slot next() is in, is my custom class derived from KDialogButtonBox(), so I get an error about not having a matching function call.

I'm essentially passing in KReminder* const (when I type 'this' into the third argument), but it expects a QObject*. Is there anyway around this?

Is the object which is the parent to your KDialogButtonBox a QWidget? Usually this is subclassed as well, so you should be doing the setup there.

No, the parent is not an object at all. I have it setup as:

<main.cpp>

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...
KReminder *mainWindow = new KReminder(0);
//Maybe I should pass 'this' instead of 0?
mainWindow->show();
...

<kreminder.cpp>

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KReminder::KReminder(QWidget *parent) : KDialogButtonBox(parent)
{}

main constructs an instance of KReminder which is subclassed from KDialogButtonBox().

I see. KReminder looks like a KDE PIM class, so I suggest you contact the KDE PIM development team for assistance, as they will know how to best use that class. kde-pim@kde.org.

Hmmm, no not a PIM class.

KReminder is what I'm making myself from scratch. I'm making a program that reminds me of appointments (you know, like the other billion programs that do this.) I'm just using this to get my feet wet in KDE programming.

I'll try kde-devel, see what they have to say.

I think someone from kde-devel pinned it down to that fact that the error message says I'm trying to pass in a const.

error: no matching function for call to ‘KReminder::addButton(KGuiItem*&, QDialogButtonBox::ButtonRole, KReminder* const, const char*)’

note: candidates are:
<snip> <a Qt version of the addButton function>

KPushButton* KDialogButtonBox::addButton(const KGuiItem&, QDialogButtonBox::ButtonRole, QObject*, const char*)
<snip> <more Qt versions of the addButton function>

As I have not declared my class as const, we have no idea where it is coming from. Any suggestions?

It is probable the function you are currently in is declared, either at the Qt or KDE level as const.

What the hell is this?

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&*this

Obvious a bad hack, but this made my code compile. I'm dereferencing a pointer then getting its' memory address? How would this work?

I have a feeling that my program will explode if I try running it. Any ideas why this allows my code to compile?

It likely removes the const-ness from the pointer. You can also do this with "const_cast<YourType*>( this );"