Synchronizes the app_list state and the home card state.

- "all apps" from BOTTOM state should switch to CENTERED state
- switching to BOTTOM state should switch to the start page

BUG=425724, 425717
R=oshima@chromium.org
TEST=the new test covers

Export HomeCardView into a separate file.

HomeCardView gets fairly complicated and it's worth exporting into
a different file.

Review URL: https://codereview.chromium.org/712133002

Cr-Commit-Position: refs/heads/master@{#303593}

5 files changed, 76 insertions, 2 deletions

diff --git a/athena/home/home_card_impl.cc b/athena/home/home_card_impl.cc
index 2e7cdd1..da75954 100644
--- a/athena/home/home_card_impl.cc
+++ b/athena/home/home_card_impl.cc
@@ -134,6 +134,7 @@ HomeCardImpl::~HomeCardImpl() {
 
   // Reset the view delegate first as it access search provider during
   // shutdown.
+  view_delegate_->GetModel()->RemoveObserver(this);
   view_delegate_.reset();
   instance = nullptr;
 }
@@ -151,6 +152,7 @@ void HomeCardImpl::Init() {
   view_delegate_.reset(
       new AppListViewDelegate(model_builder_.get(), search_factory_.get()));
 
+  view_delegate_->GetModel()->AddObserver(this);
   home_card_view_ = new HomeCardView(view_delegate_.get(), this);
   home_card_widget_ = new views::Widget();
   views::Widget::InitParams widget_params(
@@ -305,6 +307,20 @@ void HomeCardImpl::OnSplitViewModeEnter() {
 void HomeCardImpl::OnSplitViewModeExit() {
 }
 
+void HomeCardImpl::OnAppListModelStateChanged(
+    app_list::AppListModel::State old_state,
+    app_list::AppListModel::State new_state) {
+  // State change should not happen in minimized mode.
+  DCHECK_NE(VISIBLE_MINIMIZED, state_);
+
+  if (state_ == VISIBLE_BOTTOM) {
+    if (old_state == app_list::AppListModel::STATE_START)
+      SetState(VISIBLE_CENTERED);
+    else
+      DCHECK_EQ(app_list::AppListModel::STATE_START, new_state);
+  }
+}
+
 // static
 HomeCard* HomeCard::Create(scoped_ptr<AppModelBuilder> model_builder,
                            scoped_ptr<SearchControllerFactory> search_factory) {
diff --git a/athena/home/home_card_impl.h b/athena/home/home_card_impl.h
index a35c31b5..08e56c5 100644
--- a/athena/home/home_card_impl.h
+++ b/athena/home/home_card_impl.h
@@ -11,6 +11,8 @@
 #include "athena/home/public/search_controller_factory.h"
 #include "athena/input/public/accelerator_manager.h"
 #include "athena/wm/public/window_manager_observer.h"
+#include "base/gtest_prod_util.h"
+#include "ui/app_list/app_list_model_observer.h"
 
 namespace app_list {
 class AppListViewDelegate;
@@ -40,7 +42,8 @@ class HomeCardView;
 class ATHENA_EXPORT HomeCardImpl : public HomeCard,
                                    public AcceleratorHandler,
                                    public HomeCardGestureManager::Delegate,
-                                   public WindowManagerObserver {
+                                   public WindowManagerObserver,
+                                   public app_list::AppListModelObserver {
  public:
   HomeCardImpl(scoped_ptr<AppModelBuilder> model_builder,
                scoped_ptr<SearchControllerFactory> search_factory);
@@ -51,6 +54,8 @@ class ATHENA_EXPORT HomeCardImpl : public HomeCard,
   aura::Window* GetHomeCardWindowForTest() const;
 
  private:
+  FRIEND_TEST_ALL_PREFIXES(HomeCardTest, AppListStates);
+
   enum Command {
     COMMAND_SHOW_HOME_CARD,
   };
@@ -80,6 +85,11 @@ class ATHENA_EXPORT HomeCardImpl : public HomeCard,
   void OnSplitViewModeEnter() override;
   void OnSplitViewModeExit() override;
 
+  // app_list::AppListModelObserver:
+  void OnAppListModelStateChanged(
+      app_list::AppListModel::State old_state,
+      app_list::AppListModel::State new_state) override;
+
   scoped_ptr<AppModelBuilder> model_builder_;
   scoped_ptr<SearchControllerFactory> search_factory_;
 
diff --git a/athena/home/home_card_unittest.cc b/athena/home/home_card_unittest.cc
index 8afa0ae..46ffccd 100644
--- a/athena/home/home_card_unittest.cc
+++ b/athena/home/home_card_unittest.cc
@@ -7,9 +7,14 @@
 #include "athena/activity/public/activity_factory.h"
 #include "athena/home/home_card_constants.h"
 #include "athena/home/home_card_impl.h"
+#include "athena/home/home_card_view.h"
 #include "athena/test/base/athena_test_base.h"
 #include "athena/test/base/test_windows.h"
 #include "athena/wm/public/window_manager.h"
+#include "ui/app_list/app_list_model.h"
+#include "ui/app_list/app_list_view_delegate.h"
+#include "ui/app_list/views/app_list_main_view.h"
+#include "ui/app_list/views/contents_view.h"
 #include "ui/aura/test/test_window_delegate.h"
 #include "ui/aura/window.h"
 #include "ui/events/test/event_generator.h"
@@ -281,4 +286,37 @@ TEST_F(HomeCardTest, DontMinimizeWithModalWindow) {
   EXPECT_TRUE(wm::IsActiveWindow(home_card));
 }
 
+TEST_F(HomeCardTest, AppListStates) {
+  app_list::AppListModel* model =
+      static_cast<HomeCardImpl*>(HomeCard::Get())->view_delegate_->GetModel();
+
+  WindowManager::Get()->EnterOverview();
+  ASSERT_EQ(HomeCard::VISIBLE_BOTTOM, HomeCard::Get()->GetState());
+  ASSERT_EQ(app_list::AppListModel::STATE_START, model->state());
+
+  // Changes the contents of the home card to "apps" view, which should change
+  // the home card state to VISIBLE_CENTERED.
+  app_list::ContentsView* contents_view =
+      static_cast<HomeCardImpl*>(HomeCard::Get())
+          ->home_card_view_->main_view_->contents_view();
+  contents_view->SetActivePage(
+      contents_view->GetPageIndexForState(app_list::AppListModel::STATE_APPS));
+  EXPECT_EQ(HomeCard::VISIBLE_CENTERED, HomeCard::Get()->GetState());
+  EXPECT_EQ(app_list::AppListModel::STATE_APPS, model->state());
+
+  // VISIBLE_BOTTOM state should always show the start page.
+  HomeCard::Get()->SetState(HomeCard::VISIBLE_BOTTOM);
+  EXPECT_EQ(app_list::AppListModel::STATE_START, model->state());
+
+  // VISIBLE_CENTERED with apps mode state to minimized -- and then back to
+  // VISIBLE_BOTTOM.
+  contents_view->SetActivePage(
+      contents_view->GetPageIndexForState(app_list::AppListModel::STATE_APPS));
+  EXPECT_EQ(app_list::AppListModel::STATE_APPS, model->state());
+  WindowManager::Get()->ExitOverview();
+  WindowManager::Get()->EnterOverview();
+  EXPECT_EQ(HomeCard::VISIBLE_BOTTOM, HomeCard::Get()->GetState());
+  EXPECT_EQ(app_list::AppListModel::STATE_START, model->state());
+}
+
 }  // namespace athena
diff --git a/athena/home/home_card_view.cc b/athena/home/home_card_view.cc
index 95ca508..120cb90 100644
--- a/athena/home/home_card_view.cc
+++ b/athena/home/home_card_view.cc
@@ -8,6 +8,7 @@
 #include "athena/wm/public/window_manager.h"
 #include "ui/app_list/app_list_view_delegate.h"
 #include "ui/app_list/views/app_list_main_view.h"
+#include "ui/app_list/views/contents_view.h"
 #include "ui/app_list/views/search_box_view.h"
 #include "ui/aura/window.h"
 #include "ui/compositor/closure_animation_observer.h"
@@ -179,6 +180,11 @@ void HomeCardView::SetStateWithAnimation(
   }
 
   main_view_->UpdateSearchBoxVisibility();
+  if (state == HomeCard::VISIBLE_BOTTOM) {
+    app_list::ContentsView* contents_view = main_view_->contents_view();
+    contents_view->SetActivePage(contents_view->GetPageIndexForState(
+        app_list::AppListModel::STATE_START));
+  }
 }
 
 void HomeCardView::ClearGesture() {
diff --git a/athena/home/home_card_view.h b/athena/home/home_card_view.h
index ffd8144..7504d2e 100644
--- a/athena/home/home_card_view.h
+++ b/athena/home/home_card_view.h
@@ -5,8 +5,10 @@
 #ifndef ATHENA_HOME_HOME_CARD_VIEW_H_
 #define ATHENA_HOME_HOME_CARD_VIEW_H_
 
+#include "athena/athena_export.h"
 #include "athena/home/home_card_gesture_manager.h"
 #include "base/callback_forward.h"
+#include "base/gtest_prod_util.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "ui/gfx/animation/tween.h"
@@ -29,7 +31,7 @@ class View;
 namespace athena {
 
 // The container view of home card contents.
-class HomeCardView : public views::WidgetDelegateView {
+class ATHENA_EXPORT HomeCardView : public views::WidgetDelegateView {
  public:
   HomeCardView(app_list::AppListViewDelegate* view_delegate,
                HomeCardGestureManager::Delegate* gesture_delegate);
@@ -53,6 +55,8 @@ class HomeCardView : public views::WidgetDelegateView {
   void Layout() override;
 
  private:
+  FRIEND_TEST_ALL_PREFIXES(HomeCardTest, AppListStates);
+
   gfx::Rect GetDragIndicatorBounds(HomeCard::State state);
 
   gfx::Rect GetMainViewBounds(HomeCard::State state);