Prevent the context menu from showing when long pressing the window controls

ui/views/widget/root_view.cc

 // 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.
 
 #include "ui/views/widget/root_view.h"
 
 #include <algorithm>
 
 #include "base/logging.h"
 #include "base/message_loop/message_loop.h"
 #include "ui/accessibility/ax_view_state.h"
 #include "ui/base/cursor/cursor.h"
 #include "ui/base/dragdrop/drag_drop_types.h"
+#include "ui/base/ui_base_switches_util.h"
 #include "ui/compositor/layer.h"
 #include "ui/events/event.h"
 #include "ui/events/keycodes/keyboard_codes.h"
 #include "ui/gfx/canvas.h"
+#include "ui/views/drag_controller.h"
 #include "ui/views/focus/view_storage.h"
 #include "ui/views/layout/fill_layout.h"
 #include "ui/views/view_targeter.h"
 #include "ui/views/views_switches.h"
 #include "ui/views/widget/widget.h"
 #include "ui/views/widget/widget_delegate.h"
 
 typedef ui::EventDispatchDetails DispatchDetails;
 
 namespace views {
@@ skipping 57 matching lines @@
       v->ShowContextMenu(location, ui::MENU_SOURCE_KEYBOARD);
       event->StopPropagation();
     }
   }
 
   View* owner_;
 
   DISALLOW_COPY_AND_ASSIGN(PreEventDispatchHandler);
 };
 
+// This event handler receives events in the post-target phase and takes care of
+// the following:
+//   - Generates context menu, or initiates drag-and-drop, from gesture events.
+class PostEventDispatchHandler : public ui::EventHandler {
+ public:
+  PostEventDispatchHandler()
+      : touch_dnd_enabled_(::switches::IsTouchDragDropEnabled()) {
+  }
+  virtual ~PostEventDispatchHandler() {}
+
+ private:
+  // Overridden from ui::EventHandler:
+  virtual void OnGestureEvent(ui::GestureEvent* event) OVERRIDE {
+    DCHECK_EQ(ui::EP_POSTTARGET, event->phase());
+    if (event->handled())
+      return;
+
+    View* target = static_cast<View*>(event->target());
+    gfx::Point location = event->location();
+    if (touch_dnd_enabled_ &&
+        event->type() == ui::ET_GESTURE_LONG_PRESS &&
+        (!target->drag_controller() ||
+         target->drag_controller()->CanStartDragForView(
+             target, location, location))) {
+      if (target->DoDrag(*event, location,
+          ui::DragDropTypes::DRAG_EVENT_SOURCE_TOUCH)) {
+        event->StopPropagation();
+        return;
+      }
+    }
+
+    if (target->context_menu_controller() &&
+        (event->type() == ui::ET_GESTURE_LONG_PRESS ||
+         event->type() == ui::ET_GESTURE_LONG_TAP ||
+         event->type() == ui::ET_GESTURE_TWO_FINGER_TAP)) {
+      gfx::Point screen_location(location);
+      View::ConvertPointToScreen(target, &screen_location);
+      target->ShowContextMenu(screen_location, ui::MENU_SOURCE_TOUCH);
+      event->StopPropagation();
+    }
+  }
+
+  bool touch_dnd_enabled_;
+
+  DISALLOW_COPY_AND_ASSIGN(PostEventDispatchHandler);
+};
+
 // static
 const char RootView::kViewClassName[] = "RootView";
 
 ////////////////////////////////////////////////////////////////////////////////
 // RootView, public:
 
 // Creation and lifetime -------------------------------------------------------
 
 RootView::RootView(Widget* widget)
     : widget_(widget),
       mouse_pressed_handler_(NULL),
       mouse_move_handler_(NULL),
       last_click_handler_(NULL),
       explicit_mouse_handler_(false),
       last_mouse_event_flags_(0),
       last_mouse_event_x_(-1),
       last_mouse_event_y_(-1),
       gesture_handler_(NULL),
       scroll_gesture_handler_(NULL),
       pre_dispatch_handler_(new internal::PreEventDispatchHandler(this)),
+      post_dispatch_handler_(new internal::PostEventDispatchHandler),
       focus_search_(this, false, false),
       focus_traversable_parent_(NULL),
       focus_traversable_parent_view_(NULL),
       event_dispatch_target_(NULL),
       old_dispatch_target_(NULL) {
   AddPreTargetHandler(pre_dispatch_handler_.get());
+  AddPostTargetHandler(post_dispatch_handler_.get());
   SetEventTargeter(scoped_ptr<ui::EventTargeter>(new ViewTargeter()));
 }
 
 RootView::~RootView() {
   // If we have children remove them explicitly so to make sure a remove
   // notification is sent for each one of them.
   if (has_children())
     RemoveAllChildViews(true);
 }
 
@@ skipping 626 matching lines @@
 
 #ifndef NDEBUG
   DCHECK(!event_dispatch_target_ || Contains(event_dispatch_target_));
 #endif
 
   return details;
 }
 
 }  // namespace internal
 }  // namespace views