Make lastPosition() result consistent among GridView and ListView

lastPosition() returns the end position of the last item so it should
always include a -1 calculation for the last item (as
FxListItemSG::endPosition() and FxGridItemSG::endPosition() do) to get
the last edge pixel of the item. With this fix, both views now
calculate startPosition() and endPosition() in the same way.

This also fixes positioning of GridView items in TopToBottom+RightToLeft
layouts. Incorrect test values in positionViewAtIndex_rightToLeft()
test are fixed (the last edge of a 1-pixel border shouldn't be visible,
since the bottom edge of a 1-pixel border is actually drawn outside,
not inside, the Rectangle).

Change-Id: I253c3836f871c61e13c08f67007ebc75e09378d6
Reviewed-on: http://codereview.qt.nokia.com/1547
Reviewed-by: Bea Lam <bea.lam@nokia.com>
Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>

4 files changed, 24 insertions, 36 deletions

diff --git a/src/declarative/items/qsggridview.cpp b/src/declarative/items/qsggridview.cpp
index ab02dea33b..24fc70851c 100644
--- a/src/declarative/items/qsggridview.cpp
+++ b/src/declarative/items/qsggridview.cpp
@@ -147,13 +147,11 @@ public:
     virtual bool isContentFlowReversed() const;
     bool isRightToLeftTopToBottom() const;
 
-    virtual qreal startPosition() const;
     virtual qreal positionAt(int index) const;
-    virtual qreal endPosition() const;
     virtual qreal endPositionAt(int index) const;
+    virtual qreal originPosition() const;
     virtual qreal lastPosition() const;
 
-    qreal originPosition() const;
     int rowSize() const;
     int colSize() const;
     qreal colPosAt(int modelIndex) const;
@@ -255,27 +253,19 @@ qreal QSGGridViewPrivate::originPosition() const
 qreal QSGGridViewPrivate::lastPosition() const
 {
     qreal pos = 0;
-    if (model && model->count())
-        pos = rowPosAt(model->count() - 1) + rowSize();
+    if (model && model->count()) {
+        // get end position of last item
+        // endPosition() of items calculate -1 to get last edge pixel, so do that here as well
+        pos = (rowPosAt(model->count() - 1) + rowSize()) - 1;
+    }
     return pos;
 }
 
-qreal QSGGridViewPrivate::startPosition() const
-{
-    return isRightToLeftTopToBottom() ? -lastPosition()+1 : originPosition();
-}
-
 qreal QSGGridViewPrivate::positionAt(int index) const
 {
     return rowPosAt(index);
 }
 
-qreal QSGGridViewPrivate::endPosition() const
-{
-    return isRightToLeftTopToBottom() ? -originPosition()+1 : lastPosition();
-
-}
-
 qreal QSGGridViewPrivate::endPositionAt(int index) const
 {
     return rowPosAt(index) + rowSize();
@@ -524,8 +514,6 @@ bool QSGGridViewPrivate::removeNonVisibleItems(int bufferFrom, int bufferTo)
 
 void QSGGridViewPrivate::visibleItemsChanged()
 {
-    Q_Q(QSGGridView);
-
     updateHeader();
     updateFooter();
     updateViewport();
@@ -680,7 +668,7 @@ void QSGGridViewPrivate::updateFooter()
             colOffset = gridItem->item->width()-cellWidth;
     }
     if (visibleItems.count()) {
-        qreal endPos = lastPosition();
+        qreal endPos = lastPosition() + 1;
         if (findLastVisibleIndex() == model->count()-1) {
             gridItem->setPosition(colOffset, endPos + rowOffset);
         } else {
diff --git a/src/declarative/items/qsgitemview.cpp b/src/declarative/items/qsgitemview.cpp
index df242ac09d..e1788ca270 100644
--- a/src/declarative/items/qsgitemview.cpp
+++ b/src/declarative/items/qsgitemview.cpp
@@ -1012,6 +1012,16 @@ qreal QSGItemViewPrivate::size() const
     return layoutOrientation() == Qt::Vertical ? q->height() : q->width();
 }
 
+qreal QSGItemViewPrivate::startPosition() const
+{
+    return isContentFlowReversed() ? -lastPosition()-1 : originPosition();
+}
+
+qreal QSGItemViewPrivate::endPosition() const
+{
+    return isContentFlowReversed() ? -originPosition()-1 : lastPosition();
+}
+
 int QSGItemViewPrivate::findLastVisibleIndex(int defaultValue) const
 {
     if (visibleItems.count()) {
diff --git a/src/declarative/items/qsgitemview_p_p.h b/src/declarative/items/qsgitemview_p_p.h
index aa1d14d5be..78f0e149f0 100644
--- a/src/declarative/items/qsgitemview_p_p.h
+++ b/src/declarative/items/qsgitemview_p_p.h
@@ -85,6 +85,8 @@ public:
     bool isValid() const;
     qreal position() const;
     qreal size() const;
+    qreal startPosition() const;
+    qreal endPosition() const;
     int findLastVisibleIndex(int defaultValue = -1) const;
     FxViewItem *visibleItem(int modelIndex) const;
     FxViewItem *firstVisibleItem() const;
@@ -165,11 +167,10 @@ protected:
     virtual Qt::Orientation layoutOrientation() const = 0;
     virtual bool isContentFlowReversed() const = 0;
 
-    virtual qreal startPosition() const = 0;
     virtual qreal positionAt(int index) const = 0;
-    virtual qreal endPosition() const = 0;
     virtual qreal endPositionAt(int index) const = 0;
-    virtual qreal lastPosition() const  = 0;
+    virtual qreal originPosition() const = 0;
+    virtual qreal lastPosition() const = 0;
 
     virtual qreal headerSize() const = 0;
     virtual qreal footerSize() const = 0;
diff --git a/src/declarative/items/qsglistview.cpp b/src/declarative/items/qsglistview.cpp
index f190e178c8..e9a592299f 100644
--- a/src/declarative/items/qsglistview.cpp
+++ b/src/declarative/items/qsglistview.cpp
@@ -187,13 +187,11 @@ public:
     virtual bool isContentFlowReversed() const;
     bool isRightToLeft() const;
 
-    virtual qreal startPosition() const;
     virtual qreal positionAt(int index) const;
-    virtual qreal endPosition() const;
     virtual qreal endPositionAt(int index) const;
+    virtual qreal originPosition() const;
     virtual qreal lastPosition() const;
 
-    qreal originPosition() const;
     FxViewItem *nextVisibleItem() const;
     FxViewItem *itemBefore(int modelIndex) const;
     QString sectionAt(int modelIndex);
@@ -362,21 +360,12 @@ qreal QSGListViewPrivate::lastPosition() const
         }
         pos = (*(--visibleItems.constEnd()))->endPosition() + invisibleCount * (averageSize + spacing);
     } else if (model && model->count()) {
-        pos = model->count() * averageSize + (model->count()-1) * spacing;
+        // endPosition() of items calculate -1 to get last edge pixel, so do that here as well
+        pos = (model->count() * averageSize + (model->count()-1) * spacing) - 1;
     }
     return pos;
 }
 
-qreal QSGListViewPrivate::startPosition() const
-{
-    return isRightToLeft() ? -lastPosition()-1 : originPosition();
-}
-
-qreal QSGListViewPrivate::endPosition() const
-{
-    return isRightToLeft() ? -originPosition()-1 : lastPosition();
-}
-
 qreal QSGListViewPrivate::positionAt(int modelIndex) const
 {
     if (FxViewItem *item = visibleItem(modelIndex))