[PyQt] QT4/QTabWidget tab add/remove/

[David Boddie]

On Sun Jun 10 00:18:35 BST 2007, S James S Stapleton wrote:

> On Friday 08 June 2007 20:23, S James S Stapleton wrote:

> > I have a tabwidget in an application where tabs are being added/removed at
> > runtime, according to loaded data and user commands. The problem is, that
> > when tabs are added, they appear in the background of the current tab, as
> > an underlay. If I cycle through the loaded tabs they dissapear. but that's
> > tedious to do every run while debugging.
> 
> The files are located here:
> http://www.thestapletons.org/jim/varapp.tbz
> 
> If you load up the "creatures.fls" file, using the file->load features
> option, you'll see the graphical glitches I was talking about.

There are two types of graphical glitch here: the first is due to the
delays in processing the data used for each tab; the second is a result of
the way you've created widgets for use with the tab widget.

There's not much that can be done about the delays you see when the data
is loaded unless you ensure that the event loop is periodically run. This
isn't causing the problems you see, so we won't look at this now.

The underlay problem is caused when widgets are created with certain
parents then reparented later. In this case, you create a feature_box
widget and put it inside a QWidget ("tmp") before passing it (not the widget)
to addTab().

Ideally, you should pass the feature_box itself to addTab() but, if each
feature_box is designed to have a parent widget, you should pass the "tmp"
QWidget instead. If you do this, you might want to remove the resize handling
code in feature_box and just place each instance of this class in a layout.
Even if you just pass "tmp" to addTab(), this will solve the underlay effect
you reported.

I also noticed that you create various widgets, and call show() and hide()
on them at various times. This might be the cause of the blank areas that
temporarily appear in the main window.

If you change line 398 of ig_moduleapp.py to

            offset = tabber.addTab(tmp, name)

does this fix some of the problems you were seeing?

David