button question

[high_flyer]

is there any widget that will do this, off the shelf?

Yes - QPushButton
Connect the clicked() signal to a slot, in that slot emit a QContextMenuEvent.

[jpn]

How about using QToolButton? It supports a menu with three different popup styles, out of the box.

[aegis]

also any guide on how to do this?

[high_flyer]

I gave you the 'guide', what more do you need?
1. create a slot
2. connect the clicked() signal to that slot
3. in the slot emit the event

[aegis]

I gave you the 'guide', what more do you need?
1. create a slot
2. connect the clicked() signal to that slot
3. in the slot emit the event

in the book c++ gui programming with qt4 i found another way{create an action, populate a menu, connect the menu with button}

oneAction= new QAction("do something!!", this);
connect(oneAction, SIGNAL(triggered()), this, SLOT(action()));
processMenu->addAction(oneAction);
menuButton->setMenu(&processMenu);

oneAction= new QAction("do something!!", this);
connect(oneAction, SIGNAL(triggered()), this, SLOT(action()));
processMenu->addAction(oneAction);
menuButton->setMenu(&processMenu);

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what is the difference? between these 2 ways?

[wysota]

That's exactly the same what Jpn suggested.

[high_flyer]

what is the difference? between these 2 ways?

The method from the book that Jpn suggested uses QActions and signals.
I find it also better, so use it.
The other method is using an event, which probably is what happens with the signal method behind the scenes.

[aegis]

Yes - QPushButton
Connect the clicked() signal to a slot, in that slot emit a QContextMenuEvent.

any guide on how to do this?