QScrollArea: fix off-by-one error in ensureWidgetVisible

If focusRect was 5 pixels past the right side of the viewport, then the
scroll area would need to be scrolled by 5 pixels. The error arises
because of this:

focusRect.right() - d->viewport->width() == 4

focusRect.right() is still inside the rectangle but width is not.
So one has to be added. Likewise for focusRect.bottom() and height.

Change-Id: Ice47a7758d136b2e4bdcbe25a33a015b37f500c1
Fixes: QTBUG-80093
Reviewed-by: Richard Moe Gustavsen <richard.gustavsen@qt.io>

1 files changed, 2 insertions, 2 deletions

diff --git a/src/widgets/widgets/qscrollarea.cpp b/src/widgets/widgets/qscrollarea.cpp
index 68aa545082..c36ec98f9a 100644
--- a/src/widgets/widgets/qscrollarea.cpp
+++ b/src/widgets/widgets/qscrollarea.cpp
@@ -490,14 +490,14 @@ void QScrollArea::ensureWidgetVisible(QWidget *childWidget, int xmargin, int yma
     if (focusRect.width() > visibleRect.width())
         d->hbar->setValue(focusRect.center().x() - d->viewport->width() / 2);
     else if (focusRect.right() > visibleRect.right())
-        d->hbar->setValue(focusRect.right() - d->viewport->width());
+        d->hbar->setValue(focusRect.right() - d->viewport->width() + 1);
     else if (focusRect.left() < visibleRect.left())
         d->hbar->setValue(focusRect.left());
 
     if (focusRect.height() > visibleRect.height())
         d->vbar->setValue(focusRect.center().y() - d->viewport->height() / 2);
     else if (focusRect.bottom() > visibleRect.bottom())
-        d->vbar->setValue(focusRect.bottom() - d->viewport->height());
+        d->vbar->setValue(focusRect.bottom() - d->viewport->height() + 1);
     else if (focusRect.top() < visibleRect.top())
         d->vbar->setValue(focusRect.top());
 }