[Issue N7298] [PATCH] QListBox ensureCurrentVisible() brokenness...

[qt-bugs at trolltech.com]

On Monday, 23 Sep 2002 20:05 Scott Wheeler wrote:
> Currently with QListBox, there are calls to ensureCurrentVisible() in
> a few
> problematic places.  Specifically it is called in resizeEvent() and
> refreshSlot() (which is called by triggerUpdate(true)).
>
> There are a few basic problems that this causes when you are using a
> QListBox
> that is larger than the view frame.  First, all calls to
> triggerUpdate() will
> artificially force the QListBox to scroll back to the selected item.
> This is
> where I initially noticed the bug, but when looking through the
> source, I
> noticed the same things happens with resizeEvent() and
> triggerUpdate(true) is
> also called by removeItem().   This affects Qt 3.0.6 and 3.1 Beta.
>

> Cheers,
>
> -Scott

Hi Scott

The following has been applied to Qt. Thanks for reporting this one.

==== //depot/qt/3.0/src/widgets/qlistbox.cpp#48 (text) ====

@@ -1590,8 +1590,11 @@

 void QListBox::removeItem( int index )
 {
+    bool wasVisible = itemVisible( currentItem() );
     delete item( index );
     triggerUpdate( TRUE );
+    if ( wasVisible )
+       ensureCurrentVisible();
 }


@@ -3646,8 +3649,10 @@
     if ( d->mustPaintAll ||
         d->layoutDirty ) {
        d->mustPaintAll = FALSE;
+       bool currentItemVisible = itemVisible( currentItem() );
        doLayout();
        if ( hasFocus() &&
+            currentItemVisible &&
             d->currentColumn >= 0 &&
             d->currentRow >= 0 &&
             ( d->columnPos[d->currentColumn] < contentsX() ||

best regards

Anders Bakken - Trolltech AS, W. Thranes gt. 98, N-0175 Oslo, Norway