Fix QListWidget scrolling with keys when there are hidden items

If the selected item is scrolled with keyboard keys the selected item
will go outside the visible area. The scrolling did not take hidden
items into account when calculating the amount to be scrolled.

Task-number: QTBUG-21804
Change-Id: I63da0248cec43be464898f9dc8167e739f00ccd0
Reviewed-by: Stephen Kelly <stephen.kelly@kdab.com>

1 files changed, 11 insertions, 3 deletions

diff --git a/src/widgets/itemviews/qlistview.cpp b/src/widgets/itemviews/qlistview.cpp
index 14c6172869..11ef2430f8 100644
--- a/src/widgets/itemviews/qlistview.cpp
+++ b/src/widgets/itemviews/qlistview.cpp
@@ -2533,13 +2533,21 @@ int QListModeViewBase::perItemScrollToValue(int index, int scrollValue, int view
 {
     if (index < 0)
         return scrollValue;
+
+    QVector<int> visibleFlowPositions;
+    visibleFlowPositions.reserve(flowPositions.count() - 1);
+    for (int i = 0; i < flowPositions.count() - 1; i++) { // flowPositions count is +1 larger than actual row count
+        if (!isHidden(i))
+            visibleFlowPositions.append(flowPositions.at(i));
+    }
+
     if (!wrap) {
         int topIndex = index;
         const int bottomIndex = topIndex;
-        const int bottomCoordinate = flowPositions.at(index);
+        const int bottomCoordinate = visibleFlowPositions.at(index);
 
         while (topIndex > 0 &&
-            (bottomCoordinate - flowPositions.at(topIndex-1) + itemExtent) <= (viewportSize)) {
+               (bottomCoordinate - visibleFlowPositions.at(topIndex - 1) + itemExtent) <= (viewportSize)) {
             topIndex--;
         }
 
@@ -2559,7 +2567,7 @@ int QListModeViewBase::perItemScrollToValue(int index, int scrollValue, int view
                                            ? Qt::Horizontal : Qt::Vertical);
         if (flowOrientation == orientation) { // scrolling in the "flow" direction
             // ### wrapped scrolling in the flow direction
-            return flowPositions.at(index); // ### always pixel based for now
+            return visibleFlowPositions.at(index); // ### always pixel based for now
         } else if (!segmentStartRows.isEmpty()) { // we are scrolling in the "segment" direction
             int segment = qBinarySearch<int>(segmentStartRows, index, 0, segmentStartRows.count() - 1);
             int leftSegment = segment;