Tablet WM : Swiping on system tray bubble.

ash/system/tray/system_tray.h

Index: ash/system/tray/system_tray.h
diff --git a/ash/system/tray/system_tray.h b/ash/system/tray/system_tray.h
index fa16c53f74067aaee8e1eacaccff91add8d1d17d..2d821b4db00ad80c7b7521b65a4a7736ed19314f 100644
--- a/ash/system/tray/system_tray.h
+++ b/ash/system/tray/system_tray.h
@@ -10,6 +10,7 @@
 #include <vector>
 
 #include "ash/ash_export.h"
+#include "ash/shell_observer.h"
 #include "ash/system/tray/system_tray_bubble.h"
 #include "ash/system/tray/tray_background_view.h"
 #include "base/macros.h"
@@ -38,6 +39,10 @@ class TrayTiles;
 class TrayUpdate;
 class WebNotificationTray;
 
+namespace test {
+class SystemTrayTest;
+}
+
 // There are different methods for creating bubble views.
 enum BubbleCreationType {
   BUBBLE_CREATE_NEW,    // Closes any existing bubble and creates a new one.
@@ -45,7 +50,8 @@ enum BubbleCreationType {
 };
 
 class ASH_EXPORT SystemTray : public TrayBackgroundView,
-                              public views::TrayBubbleView::Delegate {
+                              public views::TrayBubbleView::Delegate,
+                              public ShellObserver {
  public:
   explicit SystemTray(Shelf* shelf);
   ~SystemTray() override;
@@ -136,14 +142,23 @@ class ASH_EXPORT SystemTray : public TrayBackgroundView,
   base::string16 GetAccessibleNameForBubble() override;
   void HideBubble(const views::TrayBubbleView* bubble_view) override;
 
+  // ShellObserver:
+  void OnMaximizeModeStarted() override;
+  void OnMaximizeModeEnded() override;
+
   ScreenTrayItem* GetScreenShareItem() { return screen_share_tray_item_; }
   ScreenTrayItem* GetScreenCaptureItem() { return screen_capture_tray_item_; }
 
   // Activates the system tray bubble.
   void ActivateBubble();
 
+  gfx::Rect GetWorkAreaBoundsInScreen() const;
+
+  bool in_maximize_mode() { return in_maximize_mode_; }
+
  private:
   friend class SystemTrayTestApi;
+  friend class test::SystemTrayTest;

[xiyuan, 2017/06/16 17:33:42]

Can you extend SystemTrayTestApi to allow setting |in_maximize_mode_| instead of
adding new friends?

[minch1, 2017/06/16 22:11:51]

Done.

   class ActivationObserver;
 
   // Closes the bubble. Used to bind as a KeyEventWatcher::KeyEventCallback.
@@ -193,6 +208,42 @@ class ASH_EXPORT SystemTray : public TrayBackgroundView,
   // Overridden from ActionableView.
   bool PerformAction(const ui::Event& event) override;
 
+  // Overridden from ui::EventHandler:
+  void OnGestureEvent(ui::GestureEvent* event) override;
+
+  // Gesture related functions:
+  bool ProcessGestureEvent(const ui::GestureEvent& event);
+  bool StartGestureDrag(const ui::GestureEvent& gesture);
+  void UpdateGestureDrag(const ui::GestureEvent& gesture);
+  void CompleteGestureDrag(const ui::GestureEvent& gesture);
+
+  // Returns true if swiping down triggered on the system tray area on the
+  // shelf.
+  bool IsSwipingDownOnShelf(const ui::GestureEvent& gesture);
+
+  // Update the bounds of the system tray bubble according to the location of
+  // the gesture.
+  void UpdateBoundsOnGesture(const ui::GestureEvent& gesture);
+
+  // Rules for showing / closing the system bubble for swiping.
+  // |ET_GESTURE_SCROLL_END| considers only the position of the dragging.
+  // |ET_SCROLL_FLING_START| should consider both position and velocity of the
+  // dragging.

[xiyuan, 2017/06/16 17:33:42]

This comment seems to be just for ShouldShowSystemBubbleForSwiping. Move it
there and document ShouldShowSystemBubbleBasedOnPosition properly.

[minch1, 2017/06/16 22:11:51]

Done.

+  bool ShouldShowSystemBubbleBasedOnPosition();

[xiyuan, 2017/06/16 17:33:42]

nit: ShouldShowSystemBubbleBasedOnPosition ->
ShouldShowSystemBubbleBasedOnDragAmount

[minch1, 2017/06/16 22:11:51]

Done.

+  bool ShouldShowSystemBubbleForSwiping(const ui::GestureEvent& gesture);
+
+  // Shelf the system tray is in.
+  Shelf* const shelf_;
+
+  // Swiping of the system tray bubble is only for maximize mode.
+  bool in_maximize_mode_ = false;
+
+  // The original bounds of the system tray bubble.
+  gfx::Rect system_tray_bubble_bounds_ = gfx::Rect();
+
+  // Tracks the amount of the drag.
+  float gesture_drag_amount_ = 0.f;
+
   // The web notification tray view that appears adjacent to this view.
   WebNotificationTray* web_notification_tray_ = nullptr;