[Chrome OS MD] Draw a 1px separator between 2 tray items

ash/common/system/tray/tray_background_view.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef ASH_COMMON_SYSTEM_TRAY_TRAY_BACKGROUND_VIEW_H_
 #define ASH_COMMON_SYSTEM_TRAY_TRAY_BACKGROUND_VIEW_H_
 
 #include <memory>
 
 #include "ash/ash_export.h"
 #include "ash/common/shelf/shelf_background_animator_observer.h"
 #include "ash/common/shelf/shelf_types.h"
 #include "ash/common/system/tray/actionable_view.h"
 #include "base/macros.h"
 #include "ui/compositor/layer_animation_observer.h"
 #include "ui/views/bubble/tray_bubble_view.h"
 
 namespace ash {
 class ShelfLayoutManager;
 class TrayEventFilter;
 class TrayBackground;
 class WmShelf;
+class WmShelfObserver;
 
 // Base class for children of StatusAreaWidget: SystemTray, WebNotificationTray,
 // LogoutButtonTray, OverviewButtonTray.
 // This class handles setting and animating the background when the Launcher
-// his shown/hidden. It also inherits from ActionableView so that the tray
+// is shown/hidden. It also inherits from ActionableView so that the tray
 // items can override PerformAction when clicked on.
 class ASH_EXPORT TrayBackgroundView : public ActionableView,
                                       public ui::ImplicitAnimationObserver,
                                       public ShelfBackgroundAnimatorObserver {
  public:
   static const char kViewClassName[];
 
   // Base class for tray containers. Sets the border and layout. The container
   // auto-resizes the widget when necessary.
   class TrayContainer : public views::View {
@@ skipping 17 matching lines @@
 
    private:
     void UpdateLayout();
 
     ShelfAlignment alignment_;
     gfx::Size size_;
 
     DISALLOW_COPY_AND_ASSIGN(TrayContainer);
   };
 
-  explicit TrayBackgroundView(WmShelf* wm_shelf);
+  // Creates a TrayBackgroundView and adds a |tray_background_view_observer| to
+  // observe when this tray visibility changes, so that the separator visibility
+  // can be updated accordingly.
+  explicit TrayBackgroundView(WmShelf* wm_shelf,

[James Cook, 2016/08/09 00:25:18]

no explicit

[yiyix, 2016/08/11 01:23:20]

Done.

+                              WmShelfObserver* wm_shelf_observer);
   ~TrayBackgroundView() override;
 
   // Called after the tray has been added to the widget containing it.
   virtual void Initialize();
 
   // Initializes animations for the bubble.
   static void InitializeBubbleAnimations(views::Widget* bubble_widget);
 
   // views::View:
   void SetVisible(bool visible) override;
   const char* GetClassName() const override;
   void ChildPreferredSizeChanged(views::View* child) override;
   void GetAccessibleState(ui::AXViewState* state) override;
   void AboutToRequestFocusFromTabTraversal(bool reverse) override;
+  void OnPaint(gfx::Canvas* canvas) override;
 
   // ActionableView:
   bool PerformAction(const ui::Event& event) override;
   gfx::Rect GetFocusBounds() override;
   void OnGestureEvent(ui::GestureEvent* event) override;
 
   // Called whenever the shelf alignment changes.
   virtual void SetShelfAlignment(ShelfAlignment alignment);
 
   // Called when the anchor (tray or bubble) may have moved or changed.
@@ skipping 38 matching lines @@
   ShelfAlignment shelf_alignment() const { return shelf_alignment_; }
   TrayEventFilter* tray_event_filter() { return tray_event_filter_.get(); }
   WmShelf* shelf() { return wm_shelf_; }
 
   // Updates the arrow visibility based on the launcher visibility.
   void UpdateBubbleViewArrow(views::TrayBubbleView* bubble_view);
 
   // ShelfBackgroundAnimatorObserver:
   void UpdateShelfItemBackground(int alpha) override;
 
+  // Updates the visibility of this tray's separator.
+  void SetSeparatorVisibility(bool is_show);
+
+ protected:
+  // In the given |canvas|, draws a 1px wide and 32dp tall separator line to the
+  // right of this TrayBackgeoundView item.

[James Cook, 2016/08/09 00:25:18]

nit: TrayBackgroundView, or just say "item"

[yiyix, 2016/08/11 01:23:20]

Done.

+  void DrawSeparator(gfx::Canvas* canvas);
+
  private:
   class TrayWidgetObserver;
 
-  // Called from Initialize after all status area trays have been created.
-  // Sets the border based on the position of the view.
-  void SetTrayBorder();
-
   // ui::ImplicitAnimationObserver:
   void OnImplicitAnimationsCompleted() override;
   bool RequiresNotificationWhenAnimatorDestroyed() const override;
 
   // Applies transformations to the |layer()| to animate the view when
   // SetVisible(false) is called.
   void HideTransformation();
 
+  // For Material Design, extra padding is added to tray items so there is
+  // enough places to draw separator between this tray and the tray to the left
+  // (if horizontally aligned) or to the bottom (if vertically aligned) if a
+  // separator is needed. No border is set for non-MD.
+  void CalculateAndSetTrayContainerBorder();
+
   // The shelf containing the system tray for this view.
   WmShelf* wm_shelf_;
 
   // Convenience pointer to the contents view.
   TrayContainer* tray_container_;
 
   // Shelf alignment.
   // TODO(jamescook): Don't cache this, get it from WmShelf.
   ShelfAlignment shelf_alignment_;
 
   // Owned by the view passed to SetContents().
   TrayBackground* background_;
 
   // This variable stores the activation override which will tint the background
   // differently if set to true.
   bool draw_background_as_active_;
 
+  WmShelfObserver* wm_shelf_observer_;
+  bool is_separator_visible_;
   std::unique_ptr<TrayWidgetObserver> widget_observer_;
   std::unique_ptr<TrayEventFilter> tray_event_filter_;
 
   DISALLOW_COPY_AND_ASSIGN(TrayBackgroundView);
 };
 
 }  // namespace ash
 
 #endif  // ASH_COMMON_SYSTEM_TRAY_TRAY_BACKGROUND_VIEW_H_