[PyKDE] context menu in QHeader

[Andrew Dalke]

Boudewijn: (from private email)
> have you tried using the event functions of QWidget? You can catch
> any mouse event anywhere using them, and then use a QPopupMenu.

A-ha, that works.

[now list email]
> QHeader inherits QWidget, which has a method, mousePressEvent(QEvent ev).
> You can find out which kind of press occurred, and also the location
> of the press. From there, it's easy to instantiate and populate a
> QPopupMenu.

I tried that, but mousePressEvent is a virtual method of the QWidget,
which (if I understand correctly) means I would need to derive from
QHeader to get that call.  I tried treating it as a signal, but PyQT
complained and wouldn't let me.

In a related question, I want the column headers to provide some
feedback during mouseover (eg, by having the background become a
lighter shade of grey).  I tried setting the options that seemed
even vaguely relevant, but none worked.

It seems I should be able to implement my own paint method to do
that, but it again requires that I be able to tell the QTable to use
my derived QHeader and not the default one.

> Keep in mind that signals/slots are meant for communication between
objects.
> Events are meant for the handling of user input -- key presses, mouse
stuff,
> things like that.

I (think) I understand.  Again, it's only been a couple of days.  But
since there was a 'contextMenuRequested' event for the cells I figured
there would also be a contextMenuRequested signal for the headers, and
it appears that there isn't.

> Have you seen
>
http://www.opendocspublishing.com/pyqt/index.lxp?lxpwrap=x2629%2ehtm#AEN2679
  ...
> where I discuss events?

Yes, I have.  Indeed, thank you for writing it because that publication
is one of the reasons I'm looking more into Qt, since I wouldn't have
wanted to figure this all on my own.

I think I follow how events work, it's just that I don't know what to
do when there isn't the event I'm looking for.  For example, I don't
recall anything in your book on event filters, nor any example close
enough to what I'm working on for me to tweak.

> As for the rest: QGrid isn't a widget, but a layout manager, actually. For
> your purpose, QTable should work best.

My mistake.  I just started with Qt a couple days ago and I'm still
lost in the maze of different names.  I meant to say QTable.

                        Andrew
                        dalke at dalkescientific.com