applist-focus: Handle arrow key focus traversal in SearchResultPageView

Changes:
1. Handle arrow up/down in SearchResultTileItemListView, so that focus
   could traverse vertically.
2. Move focus to search box when it is moved outside
   SearchResultPageView during vertical focus traversal.

Design Doc: go/applist-focus

BUG=766810
TEST=AppListViewFocusTest.*

Change-Id: Idcd54e7d7c4f2cd6fe425e80218310581c7bcaaa
Reviewed-on: https://chromium-review.googlesource.com/701578
Commit-Queue: Weidong Guo <weidongg@chromium.org>
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#506849}

ui/app_list/views/app_list_view_unittest.cc

@@ -556,8 +556,8 @@ TEST_F(AppListViewFocusTest, LinearFocusTraversalInHalfState) {
   // fake search results.
   search_box_view()->search_box()->InsertText(base::UTF8ToUTF16("test"));
   EXPECT_EQ(app_list_view()->app_list_state(), AppListView::HALF);
-  const int kTileResults = 3;
-  const int kListResults = 2;
+  constexpr int kTileResults = 3;
+  constexpr int kListResults = 2;
   SetUpSearchResults(kTileResults, kListResults);
 
   std::vector<views::View*> forward_view_list;
@@ -705,6 +705,46 @@ TEST_F(AppListViewFocusTest, VerticalFocusTraversalInFullscreenAllAppsState) {
   TestFocusTraversal(backward_view_list, ui::VKEY_UP, false);
 }
 
+// Tests the vertical focus traversal in HALF state with opened search box.
+TEST_F(AppListViewFocusTest, VerticalFocusTraversalInHalfState) {
+  Show();
+
+  // Type something in search box to transition to HALF state and populate
+  // fake search results.
+  search_box_view()->search_box()->InsertText(base::UTF8ToUTF16("test"));
+  EXPECT_EQ(app_list_view()->app_list_state(), AppListView::HALF);
+  constexpr int kTileResults = 3;
+  constexpr int kListResults = 2;
+  SetUpSearchResults(kTileResults, kListResults);
+
+  std::vector<views::View*> forward_view_list;
+  forward_view_list.push_back(search_box_view()->search_box());
+  const std::vector<SearchResultTileItemView*>& tile_views =
+      contents_view()
+          ->search_result_tile_item_list_view_for_test()
+          ->tile_views_for_test();
+  forward_view_list.push_back(tile_views[0]);
+  views::View* results_container = contents_view()
+                                       ->search_result_list_view_for_test()
+                                       ->results_container_for_test();
+  for (int i = 0; i < kListResults; ++i)
+    forward_view_list.push_back(results_container->child_at(i));
+  forward_view_list.push_back(search_box_view()->search_box());
+
+  // Test traversal triggered by down.
+  TestFocusTraversal(forward_view_list, ui::VKEY_DOWN, false);
+
+  std::vector<views::View*> backward_view_list;
+  backward_view_list.push_back(search_box_view()->search_box());
+  for (int i = kListResults - 1; i >= 0; --i)
+    backward_view_list.push_back(results_container->child_at(i));
+  backward_view_list.push_back(tile_views[kTileResults - 1]);
+  backward_view_list.push_back(search_box_view()->search_box());
+
+  // Test traversal triggered by up.
+  TestFocusTraversal(backward_view_list, ui::VKEY_UP, false);
+}
+
 // Tests the vertical focus traversal in FULLSCREEN_ALL_APPS state within
 // folder.
 TEST_F(AppListViewFocusTest, VerticalFocusTraversalInFolder) {

ui/app_list/views/contents_view.cc

@@ -90,7 +90,8 @@ void ContentsView::Init(AppListModel* model) {
   }
 
   search_result_tile_item_list_view_ = new SearchResultTileItemListView(
-      GetSearchBoxView()->search_box(), view_delegate);
+      search_results_page_view_, GetSearchBoxView()->search_box(),
+      view_delegate);
   search_results_page_view_->AddSearchResultContainerView(
       results, search_result_tile_item_list_view_);
 

ui/app_list/views/search_result_page_view.cc

@@ -23,6 +23,7 @@
 #include "ui/views/background.h"
 #include "ui/views/controls/scroll_view.h"
 #include "ui/views/controls/scrollbar/overlay_scroll_bar.h"
+#include "ui/views/controls/textfield/textfield.h"
 #include "ui/views/layout/box_layout.h"
 #include "ui/views/layout/fill_layout.h"
 #include "ui/views/shadow_border.h"
@@ -76,6 +77,15 @@ class ZeroWidthVerticalScrollBar : public views::OverlayScrollBar {
   // OverlayScrollBar overrides:
   int GetThickness() const override { return 0; }
 
+  bool OnKeyPressed(const ui::KeyEvent& event) override {
+    if (!features::IsAppListFocusEnabled())
+      return OverlayScrollBar::OnKeyPressed(event);
+
+    // Arrow keys should be handled by FocusManager to move focus. When a search
+    // result is focued, it will be set visible in scroll view.
+    return false;
+  }
+
  private:
   DISALLOW_COPY_AND_ASSIGN(ZeroWidthVerticalScrollBar);
 };
@@ -215,7 +225,28 @@ void SearchResultPageView::AddSearchResultContainerView(
 
 bool SearchResultPageView::OnKeyPressed(const ui::KeyEvent& event) {
   if (is_app_list_focus_enabled_) {
-    // TODO(weidongg/766810) Add handling of arrow up and down here.
+    views::View* next_focusable_view = nullptr;
+    if (event.key_code() == ui::VKEY_UP) {
+      next_focusable_view = GetFocusManager()->GetNextFocusableView(
+          GetFocusManager()->GetFocusedView(), GetWidget(), true, false);
+    } else if (event.key_code() == ui::VKEY_DOWN) {
+      next_focusable_view = GetFocusManager()->GetNextFocusableView(
+          GetFocusManager()->GetFocusedView(), GetWidget(), false, false);
+    }
+
+    if (next_focusable_view && !Contains(next_focusable_view)) {
+      // Hitting up key when focus is on first search result or hitting down
+      // key when focus is on last search result should move focus onto search
+      // box.
+      AppListPage::contents_view()
+          ->GetSearchBoxView()
+          ->search_box()
+          ->RequestFocus();
+      return true;
+    }
+
+    // Return false to let FocusManager to handle default focus move by key
+    // events.
     return false;
   }
   // TODO(weidongg/766807) Remove everything below when the flag is enabled by

ui/app_list/views/search_result_tile_item_list_view.cc

@@ -11,6 +11,7 @@
 #include "ui/app_list/app_list_features.h"
 #include "ui/app_list/app_list_view_delegate.h"
 #include "ui/app_list/search_result.h"
+#include "ui/app_list/views/search_result_page_view.h"
 #include "ui/app_list/views/search_result_tile_item_view.h"
 #include "ui/gfx/geometry/insets.h"
 #include "ui/views/background.h"
@@ -42,9 +43,11 @@ constexpr SkColor kSeparatorColor = SkColorSetARGBMacro(0x1F, 0x00, 0x00, 0x00);
 namespace app_list {
 
 SearchResultTileItemListView::SearchResultTileItemListView(
+    SearchResultPageView* search_result_page_view,
     views::Textfield* search_box,
     AppListViewDelegate* view_delegate)
-    : search_box_(search_box),
+    : search_result_page_view_(search_result_page_view),
+      search_box_(search_box),
       is_play_store_app_search_enabled_(
           features::IsPlayStoreAppSearchEnabled()),
       is_fullscreen_app_list_enabled_(features::IsFullscreenAppListEnabled()) {
@@ -191,10 +194,33 @@ void SearchResultTileItemListView::UpdateSelectedIndex(int old_selected,
 
 bool SearchResultTileItemListView::OnKeyPressed(const ui::KeyEvent& event) {
   if (features::IsAppListFocusEnabled()) {
-    // TODO(weidongg/766807) Remove this function when the flag is enabled by
-    // default.
+    views::View* next_focusable_view = nullptr;
+
+    // Since search result tile item views have horizontal layout, hitting
+    // up/down when one of them is focused moves focus to the previous/next
+    // search result container.
+    if (event.key_code() == ui::VKEY_UP) {
+      next_focusable_view = GetFocusManager()->GetNextFocusableView(
+          tile_views_.front(), GetWidget(), true, false);
+      if (!search_result_page_view_->Contains(next_focusable_view)) {
+        // Focus should be moved to search box when it is moved outside search
+        // result page view.
+        search_box_->RequestFocus();
+        return true;
+      }
+    } else if (event.key_code() == ui::VKEY_DOWN) {
+      next_focusable_view = GetFocusManager()->GetNextFocusableView(
+          tile_views_.back(), GetWidget(), false, false);
+    }
+
+    if (next_focusable_view) {
+      next_focusable_view->RequestFocus();
+      return true;
+    }
     return false;
   }
+  // TODO(weidongg/766807) Remove everything below when the flag is enabled by
+  // default.
   int selection_index = selected_index();
   // Also count the separator when Play Store app search feature is enabled.
   const int child_index = is_play_store_app_search_enabled_

ui/app_list/views/search_result_tile_item_list_view.h

@@ -18,14 +18,16 @@ class Separator;
 namespace app_list {
 
 class AppListViewDelegate;
+class SearchResultPageView;
 class SearchResultTileItemView;
 
 // Displays a list of SearchResultTileItemView.
 class APP_LIST_EXPORT SearchResultTileItemListView
     : public SearchResultContainerView {
  public:
-  explicit SearchResultTileItemListView(views::Textfield* search_box,
-                                        AppListViewDelegate* view_delegate);
+  SearchResultTileItemListView(SearchResultPageView* search_result_page_view,
+                               views::Textfield* search_box,
+                               AppListViewDelegate* view_delegate);
   ~SearchResultTileItemListView() override;
 
   // Overridden from SearchResultContainerView:
@@ -52,7 +54,9 @@ class APP_LIST_EXPORT SearchResultTileItemListView
 
   std::vector<views::Separator*> separator_views_;
 
-  views::Textfield* search_box_;  // Owned by the views hierarchy.
+  // Owned by the views hierarchy.
+  SearchResultPageView* const search_result_page_view_;
+  views::Textfield* search_box_;
 
   const bool is_play_store_app_search_enabled_;
 

ui/app_list/views/search_result_tile_item_list_view_unittest.cc

@@ -56,8 +56,8 @@ class SearchResultTileItemListViewTest
 
     // Sets up the views.
     textfield_ = base::MakeUnique<views::Textfield>();
-    view_ = base::MakeUnique<SearchResultTileItemListView>(textfield_.get(),
-                                                           &view_delegate_);
+    view_ = base::MakeUnique<SearchResultTileItemListView>(
+        nullptr, textfield_.get(), &view_delegate_);
     view_->SetResults(view_delegate_.GetModel()->results());
   }
 

ui/app_list/views/search_result_tile_item_view.cc

@@ -234,6 +234,8 @@ void SearchResultTileItemView::OnFocus() {
       view_delegate_->GetModel()->state() == AppListModel::STATE_APPS) {
     // Go back to first page when app in suggestions container is focused.
     pagination_model_->SelectPage(0, false);
+  } else if (!is_recommendation()) {
+    ScrollRectToVisible(GetLocalBounds());
   }
   TileItemView::OnFocus();
 }

ui/app_list/views/search_result_view.cc

@@ -186,6 +186,11 @@ void SearchResultView::SetSelected(bool selected) {
   if (selected_ == selected)
     return;
   selected_ = selected;
+
+  if (features::IsAppListFocusEnabled() && selected_) {
+    ScrollRectToVisible(GetLocalBounds());
+    NotifyAccessibilityEvent(ui::AX_EVENT_SELECTION, true);
+  }
   SchedulePaint();
 }