Experimental app list: Added a current page indicator to the launcher.

Adds a current page indicator to the launcher when the experimental app launcher is enabled.

BUG=391642

Review URL: https://codereview.chromium.org/380613002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@282335 0039d316-1c4b-4281-b951-d872f2087c98

8 files changed, 114 insertions, 10 deletions

diff --git a/ui/app_list/app_list_constants.cc b/ui/app_list/app_list_constants.cc
index 46ce92e..94d196f 100644
--- a/ui/app_list/app_list_constants.cc
+++ b/ui/app_list/app_list_constants.cc
@@ -74,6 +74,10 @@ const int kExperimentalPreferredRows = 3;
 // Radius of the circle, in which if entered, show re-order preview.
 const int kReorderDroppingCircleRadius = 35;
 
+// Height of separator between the main view and contents switcher and of
+// the launcher page indicator.
+const int kContentsSwitcherSeparatorHeight = 1;
+
 // Max items allowed in a folder.
 size_t kMaxFolderItems = 16;
 
diff --git a/ui/app_list/app_list_constants.h b/ui/app_list/app_list_constants.h
index a1937d5..f6477ed 100644
--- a/ui/app_list/app_list_constants.h
+++ b/ui/app_list/app_list_constants.h
@@ -56,6 +56,8 @@ APP_LIST_EXPORT extern const int kExperimentalPreferredRows;
 
 APP_LIST_EXPORT extern const int kReorderDroppingCircleRadius;
 
+APP_LIST_EXPORT extern const int kContentsSwitcherSeparatorHeight;
+
 APP_LIST_EXPORT extern size_t kMaxFolderItems;
 APP_LIST_EXPORT extern const size_t kNumFolderTopItems;
 APP_LIST_EXPORT extern const size_t kMaxFolderNameChars;
diff --git a/ui/app_list/views/app_list_background.cc b/ui/app_list/views/app_list_background.cc
index 19085e6..aca3f75 100644
--- a/ui/app_list/views/app_list_background.cc
+++ b/ui/app_list/views/app_list_background.cc
@@ -88,7 +88,10 @@ void AppListBackground::Paint(gfx::Canvas* canvas,
       const gfx::Rect contents_view_view_bounds =
           contents_view->ConvertRectToWidget(contents_view->GetLocalBounds());
       gfx::Rect separator_rect(contents_rect);
-      separator_rect.set_y(contents_view_view_bounds.bottom());
+      // Extra kContentsSwitcherSeparatorHeight pixels so the launcher page
+      // indicator overlays the separator rect.
+      separator_rect.set_y(contents_view_view_bounds.bottom() +
+                           kContentsSwitcherSeparatorHeight);
       separator_rect.set_height(kBottomSeparatorSize);
       canvas->FillRect(separator_rect, kBottomSeparatorColor);
       int contents_switcher_top = separator_rect.bottom();
diff --git a/ui/app_list/views/app_list_main_view.cc b/ui/app_list/views/app_list_main_view.cc
index 06cbc6a..2cbe4f6 100644
--- a/ui/app_list/views/app_list_main_view.cc
+++ b/ui/app_list/views/app_list_main_view.cc
@@ -139,7 +139,7 @@ void AppListMainView::AddContentsViews() {
   contents_view_ = new ContentsView(this);
   if (app_list::switches::IsExperimentalAppListEnabled()) {
     contents_switcher_view_ = new ContentsSwitcherView(contents_view_);
-    contents_view_->set_contents_switcher_view(contents_switcher_view_);
+    contents_view_->SetContentsSwitcherView(contents_switcher_view_);
   }
   contents_view_->InitNamedPages(model_, delegate_);
   AddChildView(contents_view_);
diff --git a/ui/app_list/views/contents_switcher_view.cc b/ui/app_list/views/contents_switcher_view.cc
index 9566943..c975065 100644
--- a/ui/app_list/views/contents_switcher_view.cc
+++ b/ui/app_list/views/contents_switcher_view.cc
@@ -6,17 +6,35 @@
 
 #include "ui/app_list/app_list_constants.h"
 #include "ui/app_list/views/contents_view.h"
+#include "ui/views/background.h"
 #include "ui/views/controls/button/custom_button.h"
 #include "ui/views/controls/button/image_button.h"
 #include "ui/views/layout/box_layout.h"
+#include "ui/views/layout/fill_layout.h"
 
 namespace app_list {
 
 namespace {
 
-const int kPreferredHeight = 32;
+const int kButtonImageSize = 32;
+const int kPreferredHeight =
+    kButtonImageSize + kContentsSwitcherSeparatorHeight;
 const int kButtonSpacing = 4;
 
+class ContentsPageIndicatorView : public views::View {
+ public:
+  ContentsPageIndicatorView() {};
+  virtual ~ContentsPageIndicatorView() {};
+
+  // Overridden from views::View:
+  virtual gfx::Size GetPreferredSize() const OVERRIDE {
+    return gfx::Size(0, kContentsSwitcherSeparatorHeight);
+  };
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(ContentsPageIndicatorView);
+};
+
 }  // namespace
 
 ContentsSwitcherView::ContentsSwitcherView(ContentsView* contents_view)
@@ -31,13 +49,37 @@ ContentsSwitcherView::~ContentsSwitcherView() {}
 
 void ContentsSwitcherView::AddSwitcherButton(int resource_id, int page_index) {
   views::ImageButton* button = new views::ImageButton(this);
+  button->SetPreferredSize(gfx::Size(kButtonImageSize, kButtonImageSize));
   if (resource_id) {
     button->SetImage(
         views::CustomButton::STATE_NORMAL,
         ui::ResourceBundle::GetSharedInstance().GetImageSkiaNamed(resource_id));
   }
   button->set_tag(page_index);
-  buttons_->AddChildView(button);
+
+  // Add an indicator for the current launcher page.
+  app_list::ContentsPageIndicatorView* indicator =
+      new app_list::ContentsPageIndicatorView();
+  indicator->set_background(
+      views::Background::CreateSolidBackground(app_list::kPagerSelectedColor));
+  indicator->SetVisible(false);
+  page_active_indicators_.push_back(indicator);
+
+  // A container view that will consume space when its child is not visible.
+  // TODO(calamity): Remove this once BoxLayout supports space-consuming
+  // invisible views.
+  views::View* indicator_container = new views::View();
+  indicator_container->SetLayoutManager(new views::FillLayout());
+  indicator_container->AddChildView(indicator);
+
+  // View containing the indicator view and image button.
+  views::View* button_container = new views::View();
+  button_container->SetLayoutManager(
+      new views::BoxLayout(views::BoxLayout::kVertical, 0, 0, 0));
+  button_container->AddChildView(indicator_container);
+  button_container->AddChildView(button);
+
+  buttons_->AddChildView(button_container);
 }
 
 gfx::Size ContentsSwitcherView::GetPreferredSize() const {
@@ -61,4 +103,36 @@ void ContentsSwitcherView::ButtonPressed(views::Button* sender,
   contents_view_->SetActivePage(sender->tag());
 }
 
+void ContentsSwitcherView::TotalPagesChanged() {
+}
+
+void ContentsSwitcherView::SelectedPageChanged(int old_selected,
+                                               int new_selected) {
+  // Makes the indicator visible when it is first drawn and when the
+  // selected page is changed.
+  int num_indicators = static_cast<int>(page_active_indicators_.size());
+  if (old_selected >= 0 && old_selected < num_indicators)
+    page_active_indicators_[old_selected]->SetVisible(false);
+
+  if (new_selected >= 0 && new_selected < num_indicators)
+    page_active_indicators_[new_selected]->SetVisible(true);
+}
+
+void ContentsSwitcherView::TransitionStarted() {
+}
+
+void ContentsSwitcherView::TransitionChanged() {
+  // Change the indicator during a launcher page transition.
+  const PaginationModel& pm = contents_view_->pagination_model();
+  int old_selected = pm.selected_page();
+  int new_selected = pm.transition().target_page;
+  if (pm.IsRevertingCurrentTransition()) {
+    // Swap the direction if the transition is reversed.
+    old_selected = pm.transition().target_page;
+    new_selected = pm.selected_page();
+  }
+
+  SelectedPageChanged(old_selected, new_selected);
+}
+
 }  // namespace app_list
diff --git a/ui/app_list/views/contents_switcher_view.h b/ui/app_list/views/contents_switcher_view.h
index 3f1bbf4..38ba280 100644
--- a/ui/app_list/views/contents_switcher_view.h
+++ b/ui/app_list/views/contents_switcher_view.h
@@ -6,6 +6,7 @@
 #define UI_APP_LIST_VIEWS_CONTENTS_SWITCHER_VIEW_H_
 
 #include "base/basictypes.h"
+#include "ui/app_list/pagination_model_observer.h"
 #include "ui/views/controls/button/button.h"
 #include "ui/views/view.h"
 
@@ -15,7 +16,9 @@ class ContentsView;
 
 // A view that contains buttons to switch the displayed view in the given
 // ContentsView.
-class ContentsSwitcherView : public views::View, public views::ButtonListener {
+class ContentsSwitcherView : public views::View,
+                             public views::ButtonListener,
+                             public PaginationModelObserver {
  public:
   explicit ContentsSwitcherView(ContentsView* contents_view);
   virtual ~ContentsSwitcherView();
@@ -36,8 +39,16 @@ class ContentsSwitcherView : public views::View, public views::ButtonListener {
   virtual void ButtonPressed(views::Button* sender,
                              const ui::Event& event) OVERRIDE;
 
+  // Overridden from PaginationModelObserver:
+  virtual void TotalPagesChanged() OVERRIDE;
+  virtual void SelectedPageChanged(int old_selected, int new_selected) OVERRIDE;
+  virtual void TransitionStarted() OVERRIDE;
+  virtual void TransitionChanged() OVERRIDE;
+
   ContentsView* contents_view_;  // Owned by views hierarchy.
   views::View* buttons_;         // Owned by views hierarchy.
+  // Stores Views owned by views hierarchy.
+  std::vector<views::View*> page_active_indicators_;
 
   DISALLOW_COPY_AND_ASSIGN(ContentsSwitcherView);
 };
diff --git a/ui/app_list/views/contents_view.cc b/ui/app_list/views/contents_view.cc
index 452e4fd..01dccd9 100644
--- a/ui/app_list/views/contents_view.cc
+++ b/ui/app_list/views/contents_view.cc
@@ -46,6 +46,8 @@ ContentsView::ContentsView(AppListMainView* app_list_main_view)
 
 ContentsView::~ContentsView() {
   pagination_model_.RemoveObserver(this);
+  if (contents_switcher_view_)
+    pagination_model_.RemoveObserver(contents_switcher_view_);
 }
 
 void ContentsView::InitNamedPages(AppListModel* model,
@@ -97,6 +99,14 @@ void ContentsView::SetDragAndDropHostOfCurrentAppList(
   apps_container_view_->SetDragAndDropHostOfCurrentAppList(drag_and_drop_host);
 }
 
+void ContentsView::SetContentsSwitcherView(
+    ContentsSwitcherView* contents_switcher_view) {
+  DCHECK(!contents_switcher_view_);
+  contents_switcher_view_ = contents_switcher_view;
+  if (contents_switcher_view_)
+    pagination_model_.AddObserver(contents_switcher_view_);
+}
+
 void ContentsView::SetActivePage(int page_index) {
   if (GetActivePageIndex() == page_index)
     return;
@@ -244,9 +254,9 @@ int ContentsView::AddLauncherPage(views::View* view, int resource_id) {
   int page_index = view_model_->view_size();
   AddChildView(view);
   view_model_->Add(view, page_index);
-  pagination_model_.SetTotalPages(view_model_->view_size());
   if (contents_switcher_view_)
     contents_switcher_view_->AddSwitcherButton(resource_id, page_index);
+  pagination_model_.SetTotalPages(view_model_->view_size());
   return page_index;
 }
 
diff --git a/ui/app_list/views/contents_view.h b/ui/app_list/views/contents_view.h
index ed2abb3..e57a0d2 100644
--- a/ui/app_list/views/contents_view.h
+++ b/ui/app_list/views/contents_view.h
@@ -65,10 +65,7 @@ class APP_LIST_EXPORT ContentsView : public views::View,
   void SetDragAndDropHostOfCurrentAppList(
       ApplicationDragAndDropHost* drag_and_drop_host);
 
-  void set_contents_switcher_view(
-      ContentsSwitcherView* contents_switcher_view) {
-    contents_switcher_view_ = contents_switcher_view;
-  }
+  void SetContentsSwitcherView(ContentsSwitcherView* contents_switcher_view);
 
   void ShowSearchResults(bool show);
   void ShowFolderContent(AppListFolderItem* folder);
@@ -110,6 +107,9 @@ class APP_LIST_EXPORT ContentsView : public views::View,
   virtual void TransitionStarted() OVERRIDE;
   virtual void TransitionChanged() OVERRIDE;
 
+  // Returns the pagination model for the ContentsView.
+  const PaginationModel& pagination_model() { return pagination_model_; }
+
  private:
   // Sets the active launcher page, accounting for whether the change is for
   // search results.