[0.9.0b2] double-clic on list item crash

[chkube]

Hello,

When I double-clic on an item of a list, it crahes.
Not every time, but very often.

I don't know if it means anything to double-clic on an item, but I did it ;-)

Christian C.

[chkube (chcouvez)]

It was on Windows version.

[Gnurou (gnurou)]

This is weird, but I cannot seem to reproduce this. Which list is it, the results list or the hierarchical one? On which kind of item does it crash - casual entry or sub-list?

[chkube (chcouvez)]

It's on the hierarchical lists, for a casual entry.
(I simply created lists of vocabulary, with the content of search result)

It does not happen every time, but at least at third time I double-clic on an element of one list.
All application windows disapear, but I have no log, no message ...

Merry Chrismas !

[Gnurou (gnurou)]

Merry Christmas! Ho-ho-ho.

Anyway allowing the double-click on casual entries was a bug, there is
no reason the allow this since they cannot contain items themselves.
So this has been deactivated. If you do not have other cases where
this happens, I think we can close this bug.

[chkube (chcouvez)]

OK to deactivate double-click, and close this bug.

[chkube (chcouvez)]

I just add a comment,
because I discovered that it happens only after moving the scroll bar.

Even if you deactivated double-click, I found a precision about this bug,
that might help if it happens in other situations (see empty lists).

And it does not happen only for casual entries, but also for empty sub-list.

If you create two lists, the second is empty, if you double-click on th empty one,
there is no problem if the first one is not displayed or big enough (not tested)
(so, if you don't have to sroll down)
But if you had to scroll down to be able to double-click on it, it crashes !

[Gnurou (gnurou)]

Indeed, I can reproduce this. Investigation is on the way...

[Gnurou (gnurou)]

Fixed. This actually seems to be a bug in Qt. When the root of an QTreeView is changed, the QTreeView::scrollContentsBy method is called if the view has been scrolled down. And in the body of this method, we have the following line:

const int itemHeight = d->defaultItemHeight <= 0 ? sizeHintForRow(0) : d->defaultItemHeight;

sizeHintForRow(0) requests the size of row 0, which does not exist in the case of empty lists, triggering the crash.

The workaround consists in scrolling back to the top whenever the root item of the list view is changed.