touch: Return an enum from OnTouchEvent.

views/view.h

 // Copyright (c) 2010 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 VIEWS_VIEW_H_
 #define VIEWS_VIEW_H_
 #pragma once
 
 #include "build/build_config.h"
 
@@ skipping 115 matching lines @@
 class View : public AcceleratorTarget {
  public:
   // Used in the versions of GetBounds() and x() that take a transformation
   // parameter in order to determine whether or not to take into account the
   // mirroring setting of the View when returning bounds positions.
   enum PositionMirroringSettings {
     IGNORE_MIRRORING_TRANSFORMATION = 0,
     APPLY_MIRRORING_TRANSFORMATION
   };
 
+#if defined(TOUCH_UI)
+  enum TouchStatus {
+    TOUCH_STATUS_UNKNOWN = 0,  // Unknown touch status. This is used to indicate
+                               // that the touch event was not handled.
+    TOUCH_STATUS_START,        // The touch event initiated a touch sequence.
+    TOUCH_STATUS_CONTINUE,     // The touch event is part of a previously
+                               // started touch sequence.
+    TOUCH_STATUS_END,          // The touch event ended the touch sequence.
+    TOUCH_STATUS_CANCEL        // The touch event was cancelled, but didn't
+                               // terminate the touch sequence.
+  };
+#endif
+
   // The view class name.
   static char kViewClassName[];
 
   View();
   virtual ~View();
 
   // Returns the amount of time between double clicks, in milliseconds.
   static int GetDoubleClickTimeMS();
 
   // Returns the amount of time to wait from hovering over a menu button until
@@ skipping 546 matching lines @@
   virtual void OnMouseEntered(const MouseEvent& event);
 
   // This method is invoked when the mouse exits this control
   // The provided event location is always (0, 0)
   // Default implementation does nothing. Override as needed.
   virtual void OnMouseExited(const MouseEvent& event);
 
 #if defined(TOUCH_UI)
   // This method is invoked for each touch event. Default implementation
   // does nothing. Override as needed.
-  virtual bool OnTouchEvent(const TouchEvent& event);
+  virtual TouchStatus OnTouchEvent(const TouchEvent& event);
 #endif
 
   // Set the MouseHandler for a drag session.
   //
   // A drag session is a stream of mouse events starting
   // with a MousePressed event, followed by several MouseDragged
   // events and finishing with a MouseReleased event.
   //
   // This method should be only invoked while processing a
   // MouseDragged or MousePressed event.
@@ skipping 439 matching lines @@
   virtual void PropagateLocaleChanged();
 
   // RootView invokes these. These in turn invoke the appropriate OnMouseXXX
   // method. If a drag is detected, DoDrag is invoked.
   bool ProcessMousePressed(const MouseEvent& e, DragInfo* drop_info);
   bool ProcessMouseDragged(const MouseEvent& e, DragInfo* drop_info);
   void ProcessMouseReleased(const MouseEvent& e, bool canceled);
 
 #if defined(TOUCH_UI)
   // RootView will invoke this with incoming TouchEvents. Returns the
-  // the result of OnTouchEvent: true if the event was handled by the
-  // callee.
-  bool ProcessTouchEvent(const TouchEvent& e);
+  // the result of OnTouchEvent.
+  TouchStatus ProcessTouchEvent(const TouchEvent& e);
 #endif
 
   // Starts a drag and drop operation originating from this view. This invokes
   // WriteDragData to write the data and GetDragOperations to determine the
   // supported drag operations. When done, OnDragDone is invoked.
   void DoDrag(const MouseEvent& e, const gfx::Point& press_pt);
 
   // Removes |view| from the hierarchy tree.  If |update_focus_cycle| is true,
   // the next and previous focusable views of views pointing to this view are
   // updated.  If |update_tool_tip| is true, the tooltip is updated.  If
@@ skipping 154 matching lines @@
   // The default value for how long to wait (in ms) before showing a menu
   // button on hover. This value is used if the OS doesn't supply one.
   static const int kShowFolderDropMenuDelay;
 
   DISALLOW_COPY_AND_ASSIGN(View);
 };
 
 }  // namespace views
 
 #endif  // VIEWS_VIEW_H_