TizenRefApp-8606 [Gallery] Implement ImageGrid autoscrolling in ScreenReader mode

Change-Id: I0cbad3fe97ed0bbdc76753f2c1aaaf0d8342a73f

2 files changed, 30 insertions, 11 deletions

diff --git a/inc/view/ImageGrid.h b/inc/view/ImageGrid.h
index af1a65b..399201b 100644
--- a/inc/view/ImageGrid.h
+++ b/inc/view/ImageGrid.h
@@ -135,6 +135,7 @@ namespace gallery {
 		void removeUnrealizeLock();
 
 		void handleItemEvent(int itemIndex, int event, int x, int y) const;
+		Elm_Interface_Atspi_Accessible *requestAtspi(int itemIndex);
 		Elm_Interface_Atspi_Accessible *getItemAtspi(int itemIndex);
 
 		// Selection mode hanling
diff --git a/src/view/ImageGrid.cpp b/src/view/ImageGrid.cpp
index 29cabf9..6c8e14c 100644
--- a/src/view/ImageGrid.cpp
+++ b/src/view/ImageGrid.cpp
@@ -140,8 +140,7 @@ namespace gallery {
 
 		virtual int calcMaxSlotCount(const int itemCount) const = 0;
 
-		virtual int calcExtraPaddingSize(const int slotSize,
-				const int itemCount) const
+		virtual int calcExtraPaddingSize(const int slotSize) const
 		{
 			return 0;
 		}
@@ -187,8 +186,8 @@ namespace gallery {
 			return ((itemCount + (totalLength - 1)) / totalLength * 2);
 		}
 
-		virtual int calcExtraPaddingSize(const int slotSize,
-				const int itemCount) const final override
+		virtual int calcExtraPaddingSize(
+				const int slotSize) const final override
 		{
 			return slotSize;
 		}
@@ -538,7 +537,7 @@ namespace gallery {
 							(m_realizeIndex + 1) :
 							(m_realizeIndex - 1));
 
-				auto relationObject = m_imageGrid.getItemAtspi(relationIndex);
+				auto relationObject = m_imageGrid.requestAtspi(relationIndex);
 				if (!relationObject) {
 					relationObject = m_btn.getEo();
 				}
@@ -1054,9 +1053,7 @@ namespace gallery {
 	Elm_Interface_Atspi_Accessible *ImageGrid::getAccessObject(
 			const bool isFlowsTo)
 	{
-		const int itemIndex = (isFlowsTo ? 0 : (m_itemCount - 1));
-		scrollToItem(itemIndex);
-		return getItemAtspi(itemIndex);
+		return getItemAtspi(isFlowsTo ? 0 : (m_itemCount - 1));
 	}
 
 	template <class FUNC>
@@ -1120,12 +1117,25 @@ namespace gallery {
 		return doWithCell(itemIndex,
 			[this, &showFunc](const int slotIndex, const int itemOffset)
 			{
-				const int scrollOffset = ((slotIndex / 2) * m_slotSize);
+				const int extraPadding = ((slotIndex & 1) ?
+						m_info.calcExtraPaddingSize(m_slotSize) : 0);
+
+				const int maxOffest = ((slotIndex / 2) * m_slotSize);
+				const int minOffset = (maxOffest + extraPadding -
+						((m_scrollerSize / m_slotSize) - 1) * m_slotSize);
+				if ((m_scrollOffset >= minOffset) &&
+						(m_scrollOffset <= maxOffest)) {
+					return RES_OK;
+				}
+
+				const int scrollOffset = ((m_scrollOffset > maxOffest) ?
+						maxOffest : minOffset);
 				if (m_info.isHorizontal) {
 					showFunc(*m_scroller, scrollOffset, 0, m_scrollerSize, 1);
 				} else {
 					showFunc(*m_scroller, 0, scrollOffset, 1, m_scrollerSize);
 				}
+
 				return RES_OK;
 			});
 	}
@@ -1186,7 +1196,7 @@ namespace gallery {
 		}
 	}
 
-	Elm_Interface_Atspi_Accessible *ImageGrid::getItemAtspi(const int itemIndex)
+	Elm_Interface_Atspi_Accessible *ImageGrid::requestAtspi(const int itemIndex)
 	{
 		if ((itemIndex < 0) || (itemIndex >= m_itemCount)) {
 			if (m_listener) {
@@ -1195,6 +1205,14 @@ namespace gallery {
 			}
 			return nullptr;
 		}
+		return getItemAtspi(itemIndex);
+	}
+
+	Elm_Interface_Atspi_Accessible *ImageGrid::getItemAtspi(
+			const int itemIndex)
+	{
+		FAIL_RETURN_VALUE(scrollToItem(itemIndex), nullptr,
+				"scrollToItem() failed!");
 
 		Elm_Interface_Atspi_Accessible *result = nullptr;
 
@@ -1391,7 +1409,7 @@ namespace gallery {
 
 		m_padSize1 = std::lround(spaceSize / 2.0);
 		m_padSize2 = (spaceSize - m_padSize1 +
-				m_info.calcExtraPaddingSize(m_slotSize, m_itemCount));
+				m_info.calcExtraPaddingSize(m_slotSize));
 	}
 
 	void ImageGrid::updateScrollBias()