Cannot flick to the end of a horizontal ListView with LayoutMirroring

Forward port of fix for QTBUG-21756.
minXExtent calculated the offset due to highlight range incorrectly
(reversed) when mirroring enabled.  Also us same algorithm for fixup()
in GridView and ListView uses.

For QtQuick 2, this change also reverses the beginning and end highlight
range, as it should be, i.e. the preferredHighlightBegin is from the
right side in RightToLeft mode.  Also added snapping tests.

Task-number: QTBUG-21756
Change-Id: Ica0ba4ab5db0ce9c77f2da75e9f8293550bd37d1
Reviewed-by: Martin Jones <martin.jones@nokia.com>

2 files changed, 10 insertions, 15 deletions

diff --git a/src/qtquick1/graphicsitems/qdeclarativegridview.cpp b/src/qtquick1/graphicsitems/qdeclarativegridview.cpp
index feabbf0387..2ed1ca1782 100644
--- a/src/qtquick1/graphicsitems/qdeclarativegridview.cpp
+++ b/src/qtquick1/graphicsitems/qdeclarativegridview.cpp
@@ -1095,23 +1095,17 @@ void QDeclarative1GridViewPrivate::fixup(AxisData &data, qreal minExtent, qreal
             bottomItem = currentItem;
         }
         qreal pos;
-        if (topItem && bottomItem && strictHighlightRange) {
-            qreal topPos = qMin(topItem->rowPos() - highlightStart, -maxExtent);
-            qreal bottomPos = qMax(bottomItem->rowPos() - highlightEnd, -minExtent);
-            pos = qAbs(data.move + topPos) < qAbs(data.move + bottomPos) ? topPos : bottomPos;
-        } else if (topItem) {
-            qreal headerPos = 0;
-            if (header)
-                headerPos = isRightToLeftTopToBottom() ? header->rowPos() + cellWidth - headerSize() : header->rowPos();
-            if (topItem->index == 0 && header && tempPosition+highlightStart < headerPos+headerSize()/2 && !strictHighlightRange) {
-                pos = isRightToLeftTopToBottom() ? - headerPos + highlightStart - size() : headerPos - highlightStart;
+        bool isInBounds = -position() > maxExtent && -position() <= minExtent;
+        if (topItem && (isInBounds || strictHighlightRange)) {
+            if (topItem->index == 0 && header && tempPosition+highlightStart < header->rowPos()+headerSize()/2 && !strictHighlightRange) {
+                pos = isRightToLeftTopToBottom() ? - header->rowPos() + highlightStart - size() : header->rowPos() - highlightStart;
             } else {
                 if (isRightToLeftTopToBottom())
                     pos = qMax(qMin(-topItem->rowPos() + highlightStart - size(), -maxExtent), -minExtent);
                 else
                     pos = qMax(qMin(topItem->rowPos() - highlightStart, -maxExtent), -minExtent);
             }
-        } else if (bottomItem) {
+        } else if (bottomItem && isInBounds) {
             if (isRightToLeftTopToBottom())
                 pos = qMax(qMin(-bottomItem->rowPos() + highlightEnd - size(), -maxExtent), -minExtent);
             else
@@ -2267,9 +2261,10 @@ qreal QDeclarative1GridView::minXExtent() const
     qreal extent = -d->startPosition();
     qreal highlightStart;
     qreal highlightEnd;
-    qreal endPositionFirstItem;
+    qreal endPositionFirstItem = 0;
     if (d->isRightToLeftTopToBottom()) {
-        endPositionFirstItem = d->rowPosAt(d->model->count()-1);
+        if (d->model && d->model->count())
+            endPositionFirstItem = d->rowPosAt(d->model->count()-1);
         highlightStart = d->highlightRangeStartValid
                 ? d->highlightRangeStart - (d->lastPosition()-endPositionFirstItem)
                 : d->size() - (d->lastPosition()-endPositionFirstItem);
@@ -2284,7 +2279,7 @@ qreal QDeclarative1GridView::minXExtent() const
             extent += d->header->item->width();
     }
     if (d->haveHighlightRange && d->highlightRange == StrictlyEnforceRange) {
-        extent += highlightStart;
+        extent += d->isRightToLeftTopToBottom() ? -highlightStart : highlightStart;
         extent = qMax(extent, -(endPositionFirstItem - highlightEnd));
     }
     return extent;
diff --git a/src/qtquick1/graphicsitems/qdeclarativelistview.cpp b/src/qtquick1/graphicsitems/qdeclarativelistview.cpp
index 7b9cb12e90..6430f6a071 100644
--- a/src/qtquick1/graphicsitems/qdeclarativelistview.cpp
+++ b/src/qtquick1/graphicsitems/qdeclarativelistview.cpp
@@ -2773,7 +2773,7 @@ qreal QDeclarative1ListView::minXExtent() const
                 d->minExtent += d->header->size();
         }
         if (d->haveHighlightRange && d->highlightRange == StrictlyEnforceRange) {
-            d->minExtent += highlightStart;
+            d->minExtent += d->isRightToLeft() ? -highlightStart : highlightStart;
             d->minExtent = qMax(d->minExtent, -(endPositionFirstItem - highlightEnd + 1));
         }
         d->minExtentDirty = false;