From 63ed8207cef00eaec0d414131ce673d20ccdd003 Mon Sep 17 00:00:00 2001
From: Romain Goyet <romain.goyet@numworks.com>
Date: Tue, 14 Jun 2016 10:52:03 +0200
Subject: [PATCH] Escher: TableView reuses cells

Change-Id: Icdbfafba351057affc2bcb74f9c967971ffee667
---
 escher/include/escher/table_view.h |  7 ++++---
 escher/src/table_view.cpp          | 11 ++++++++---
 2 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/escher/include/escher/table_view.h b/escher/include/escher/table_view.h
index 70ac44d39..f911790ac 100644
--- a/escher/include/escher/table_view.h
+++ b/escher/include/escher/table_view.h
@@ -6,8 +6,8 @@
 class TableViewDataSource {
 public:
   virtual int numberOfCells() = 0;
-  virtual View * cellAtIndex(int index) = 0;
-  virtual void willDisplayCellAtIndex(int index) = 0;
+  virtual View * reusableCell(int index) = 0;
+  virtual void willDisplayCellForIndex(View * cell, int index) = 0;
   virtual KDCoordinate cellHeight() = 0;
 };
 
@@ -28,9 +28,10 @@ private:
     void layoutSubviews() override;
   protected:
 #if ESCHER_VIEW_LOGGING
-  const char * className() const override;
+    const char * className() const override;
 #endif
   private:
+    int numberOfDisplayableCells() const;
     int cellScrollingOffset();
     TableViewDataSource * m_dataSource;
   };
diff --git a/escher/src/table_view.cpp b/escher/src/table_view.cpp
index 3d25b672c..223bb822b 100644
--- a/escher/src/table_view.cpp
+++ b/escher/src/table_view.cpp
@@ -30,13 +30,14 @@ TableView::ContentView::ContentView(TableViewDataSource * dataSource) :
 }
 
 int TableView::ContentView::numberOfSubviews() const {
-  int numberOfDisplayableCells = m_frame.height / m_dataSource->cellHeight();
-  return MIN(m_dataSource->numberOfCells(), numberOfDisplayableCells);
+  return MIN(m_dataSource->numberOfCells(), numberOfDisplayableCells());
 }
 
 View * TableView::ContentView::subview(int index) {
   int offset = cellScrollingOffset();
-  return m_dataSource->cellAtIndex(offset+index);
+  View * cell = m_dataSource->reusableCell(index);
+  m_dataSource->willDisplayCellForIndex(cell, offset+index);
+  return cell;
 }
 
 void TableView::ContentView::storeSubviewAtIndex(View * view, int index) {
@@ -59,6 +60,10 @@ void TableView::ContentView::layoutSubviews() {
   }
 }
 
+int TableView::ContentView::numberOfDisplayableCells() const {
+  return m_frame.height / m_dataSource->cellHeight();
+}
+
 // Index of the topmost cell
 int TableView::ContentView::cellScrollingOffset() {
   /* Here, we want to translate the offset at which our superview is displaying