[Escher] Implement a StackViewController

Change-Id: I1b4ecc996a1af2bef1b8ce6cfa71457d3345c00e

escher/src/stack_view_controller.cpp

@@ -0,0 +1,100 @@
+extern "C" {
+#include <assert.h>
+}
+#include <escher/stack_view_controller.h>
+#include <escher/app.h>
+
+StackViewController::ControllerView::ControllerView() :
+  View(),
+  m_contentView(nullptr),
+  m_numberOfStacks(0)
+{
+}
+
+void StackViewController::ControllerView::setContentView(View * view) {
+  m_contentView = view;
+  layoutSubviews();
+  markRectAsDirty(bounds());
+}
+
+void StackViewController::ControllerView::pushStack(const char * name) {
+  m_stackViews[m_numberOfStacks].setName(name);
+  m_numberOfStacks++;
+}
+
+void StackViewController::ControllerView::popStack() {
+  assert(m_numberOfStacks > 0);
+  m_numberOfStacks--;
+}
+
+void StackViewController::ControllerView::layoutSubviews() {
+  KDCoordinate stackHeight = 20;
+  KDCoordinate width = m_frame.width();
+  for (int i=0; i<m_numberOfStacks; i++) {
+    m_stackViews[i].setFrame(KDRect(0, stackHeight*i, width, stackHeight));
+  }
+  if (m_contentView) {
+    KDRect contentViewFrame = KDRect( 0, m_numberOfStacks*stackHeight,
+        width, m_frame.height() - m_numberOfStacks*stackHeight);
+    m_contentView->setFrame(contentViewFrame);
+  }
+}
+
+int StackViewController::ControllerView::numberOfSubviews() const {
+  return m_numberOfStacks + (m_contentView == nullptr ? 0 : 1);
+}
+
+View * StackViewController::ControllerView::subviewAtIndex(int index) {
+  if (index < m_numberOfStacks) {
+    assert(index >= 0);
+    return &m_stackViews[index];
+  } else {
+    assert(index == m_numberOfStacks);
+    return m_contentView;
+  }
+}
+
+#if ESCHER_VIEW_LOGGING
+const char * StackViewController::ControllerView::className() const {
+  return "StackViewController::ControllerView";
+}
+#endif
+
+StackViewController::StackViewController(Responder * parentResponder) :
+  ViewController(parentResponder),
+  m_numberOfChildren(0)
+{
+}
+
+void StackViewController::push(ViewController * vc) {
+  m_view.pushStack("name");
+  m_children[m_numberOfChildren++] = vc;
+  setupActiveViewController();
+}
+
+void StackViewController::pop() {
+  m_view.popStack();
+  assert(m_numberOfChildren > 0);
+  m_numberOfChildren--;
+  setupActiveViewController();
+}
+
+void StackViewController::setupActiveViewController() {
+  ViewController * vc = m_children[m_numberOfChildren-1];
+  //vc->setParentResponder(this);
+  m_view.setContentView(vc->view());
+  app()->focus(vc);
+}
+
+void StackViewController::handleKeyEvent(int key) {
+  // Switch tabs!
+}
+
+
+bool StackViewController::handleEvent(ion_event_t event) {
+  return false;
+}
+
+View * StackViewController::view() {
+  return &m_view;
+}