[escher] create a class selectable table view

Change-Id: I4e6372ed7d586d35b9b96f8cb1d29bf693713dda

escher/Makefile

@@ -10,6 +10,7 @@ objs += $(addprefix escher/src/,\
   invocation.o\
   input_view_controller.o\
   list_view.o\
+  list_view_cell.o\
   list_view_data_source.o\
   metric.o\
   palette.o\
@@ -17,6 +18,7 @@ objs += $(addprefix escher/src/,\
   responder.o\
   scroll_view.o\
   scroll_view_indicator.o\
+  selectable_table_view.o\
   simple_list_view_data_source.o\
   simple_table_view_data_source.o\
   solid_color_view.o\
@@ -29,7 +31,6 @@ objs += $(addprefix escher/src/,\
   tab_view_controller.o\
   table_view.o\
   table_view_cell.o\
-  list_view_cell.o\
   table_view_data_source.o\
   text_field.o\
   text_list_view_cell.o\

escher/include/escher.h

@@ -19,6 +19,7 @@
 #include <escher/responder.h>
 #include <escher/scroll_view.h>
 #include <escher/scroll_view_indicator.h>
+#include <escher/selectable_table_view.h>
 #include <escher/simple_table_view_data_source.h>
 #include <escher/simple_list_view_data_source.h>
 #include <escher/solid_color_view.h>

escher/include/escher/selectable_table_view.h

@@ -0,0 +1,30 @@
+#ifndef ESCHER_SELECTABLE_TABLE_VIEW_H
+#define ESCHER_SELECTABLE_TABLE_VIEW_H
+
+#include <escher/table_view.h>
+#include <escher/app.h>
+#include <escher/table_view_data_source.h>
+#include <escher/responder.h>
+
+/* SelectableTableView is a Table View that handles selection. To implement it,
+ * it needs a class which should be both data source and view controller. This
+ * takes the selectable table view as instance variable and makes it first
+ * responder. The selectable table view bubles up events when they do not
+ * concern selection. */
+
+class SelectableTableView : public TableView, public Responder {
+public:
+  SelectableTableView(Responder * parentResponder, TableViewDataSource * dataSource, KDCoordinate topMargin, 
+    KDCoordinate rightMargin, KDCoordinate bottomMargin, KDCoordinate leftMargin);
+  int selectedRow();
+  int selectedColumn();
+  virtual bool handleEvent(Ion::Events::Event event) override;
+  virtual void didBecomeFirstResponder() override;
+  void deselectTable();
+  bool setSelectedCellAtLocation(int i, int j);
+private:
+  int m_selectedCellX;
+  int m_selectedCellY;
+};
+
+#endif

escher/src/selectable_table_view.cpp

@@ -0,0 +1,66 @@
+#include <escher/selectable_table_view.h>
+
+SelectableTableView::SelectableTableView(Responder * parentResponder, TableViewDataSource * dataSource, 
+  KDCoordinate topMargin, KDCoordinate rightMargin, KDCoordinate bottomMargin, KDCoordinate leftMargin) :
+  TableView(dataSource, topMargin, rightMargin, bottomMargin, leftMargin),
+  Responder(parentResponder),
+  m_selectedCellX(0),
+  m_selectedCellY(-1)
+{
+}
+
+int SelectableTableView::selectedRow() {
+  return m_selectedCellY;
+}
+
+int SelectableTableView::selectedColumn() {
+  return m_selectedCellX;
+}
+
+void SelectableTableView::didBecomeFirstResponder() {
+  reloadData();
+}
+
+void SelectableTableView::deselectTable() {
+  TableViewCell * previousCell = cellAtLocation(m_selectedCellX, m_selectedCellY);
+  previousCell->setHighlighted(false);
+  m_selectedCellX = 0;
+  m_selectedCellY = -1;
+}
+
+bool SelectableTableView::setSelectedCellAtLocation(int i, int j) {
+  if (i < 0 || i >= dataSource()->numberOfColumns()) {
+    return false;
+  }
+  if (j < 0 || j >= dataSource()->numberOfRows()) {
+    return false;
+  }
+
+  if (m_selectedCellY >= 0) {
+    TableViewCell * previousCell = cellAtLocation(m_selectedCellX, m_selectedCellY);
+    previousCell->setHighlighted(false);
+  }
+  m_selectedCellX = i;
+  m_selectedCellY = j;
+  if (m_selectedCellY >= 0) {
+    scrollToCell(i, j);
+    TableViewCell * cell = cellAtLocation(i, j);
+    cell->setHighlighted(true);
+  }
+  return true;
+}
+
+bool SelectableTableView::handleEvent(Ion::Events::Event event) {
+  switch (event) {
+    case Ion::Events::Event::DOWN_ARROW:
+      return setSelectedCellAtLocation(m_selectedCellX, m_selectedCellY+1);
+    case Ion::Events::Event::UP_ARROW:
+      return setSelectedCellAtLocation(m_selectedCellX, m_selectedCellY-1);
+    case Ion::Events::Event::LEFT_ARROW:
+      return setSelectedCellAtLocation(m_selectedCellX-1, m_selectedCellY);
+    case Ion::Events::Event::RIGHT_ARROW:
+      return setSelectedCellAtLocation(m_selectedCellX+1, m_selectedCellY);
+    default:
+      return false;
+  }
+}