Makes MouseWatcher work while in metro mode

ui/views/mouse_watcher.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/mouse_watcher.h"
 
 #include "base/bind.h"
 #include "base/compiler_specific.h"
 #include "base/event_types.h"
 #include "base/memory/weak_ptr.h"
 #include "base/message_loop/message_loop.h"
 #include "ui/events/event_constants.h"
 #include "ui/events/event_utils.h"
 #include "ui/gfx/screen.h"
 
+#if defined(USE_AURA)
+#include "ui/aura/env.h"
+#include "ui/aura/window.h"
+#include "ui/events/event.h"
+#include "ui/events/event_handler.h"
+#endif
+
 namespace views {
 
 // Amount of time between when the mouse moves outside the Host's zone and when
 // the listener is notified.
 const int kNotifyListenerTimeMs = 300;
 
+#if defined(OS_WIN) && !defined(USE_AURA)

[sky, 2013/11/05 18:52:56]

I'm going with totally different ifdefs since hopefully soon we can nuke all the
non-aura code.

 class MouseWatcher::Observer : public base::MessageLoopForUI::Observer {
  public:
   explicit Observer(MouseWatcher* mouse_watcher)
       : mouse_watcher_(mouse_watcher),
         notify_listener_factory_(this) {
     base::MessageLoopForUI::current()->AddObserver(this);
   }
 
   virtual ~Observer() {
     base::MessageLoopForUI::current()->RemoveObserver(this);
   }
 
   // MessageLoop::Observer implementation:
-#if defined(OS_WIN)
   virtual base::EventStatus WillProcessEvent(
       const base::NativeEvent& event) OVERRIDE {
     return base::EVENT_CONTINUE;
   }
 
   virtual void DidProcessEvent(const base::NativeEvent& event) OVERRIDE {
     // We spy on three different Windows messages here to see if the mouse has
     // moved out of the bounds of the current view. The messages are:
     //
     // WM_MOUSEMOVE:
     //   For when the mouse moves from the view into the rest of the browser UI,
     //   i.e. within the bounds of the same windows HWND.
     // WM_MOUSELEAVE:
     //   For when the mouse moves out of the bounds of the view's HWND.
     // WM_NCMOUSELEAVE:
     //   For notification when the mouse leaves the _non-client_ area.
     //
     switch (event.message) {
       case WM_MOUSEMOVE:
         HandleGlobalMouseMoveEvent(MouseWatcherHost::MOUSE_MOVE);
         break;
       case WM_MOUSELEAVE:
       case WM_NCMOUSELEAVE:
         HandleGlobalMouseMoveEvent(MouseWatcherHost::MOUSE_EXIT);
         break;
     }
   }
-#elif defined(USE_AURA)
-  virtual base::EventStatus WillProcessEvent(
-      const base::NativeEvent& event) OVERRIDE {
-    return base::EVENT_CONTINUE;
-  }
-  virtual void DidProcessEvent(const base::NativeEvent& event) OVERRIDE {
-    switch (ui::EventTypeFromNative(event)) {
-      case ui::ET_MOUSE_MOVED:
-      case ui::ET_MOUSE_DRAGGED:
-        // DRAGGED is a special case of MOVED. See events_win.cc/events_x.cc.
-        HandleGlobalMouseMoveEvent(MouseWatcherHost::MOUSE_MOVE);
-        break;
-      case ui::ET_MOUSE_EXITED:
-        HandleGlobalMouseMoveEvent(MouseWatcherHost::MOUSE_EXIT);
-        break;
-      default:
-        break;
-    }
-  }
-#endif
 
  private:
   MouseWatcherHost* host() const { return mouse_watcher_->host_.get(); }
 
   // Called from the message loop observer when a mouse movement has occurred.
   void HandleGlobalMouseMoveEvent(MouseWatcherHost::MouseEventType event_type) {
     bool contained = host()->Contains(
         // TODO(scottmg): Native is wrong http://crbug.com/133312
         gfx::Screen::GetNativeScreen()->GetCursorScreenPoint(),
         event_type);
     if (!contained) {
       // Mouse moved outside the host's zone, start a timer to notify the
       // listener.
       if (!notify_listener_factory_.HasWeakPtrs()) {
+        base::MessageLoop::current()->PostDelayedTask(
+            FROM_HERE,
+            base::Bind(&Observer::NotifyListener,
+                       notify_listener_factory_.GetWeakPtr()),
+            event_type == MouseWatcherHost::MOUSE_MOVE
+                ? base::TimeDelta::FromMilliseconds(kNotifyListenerTimeMs)
+                : mouse_watcher_->notify_on_exit_time_);
+      }
+    } else {
+      // Mouse moved quickly out of the host and then into it again, so cancel
+      // the timer.
+      notify_listener_factory_.InvalidateWeakPtrs();
+    }
+  }
+
+  void NotifyListener() {
+    mouse_watcher_->NotifyListener();
+    // WARNING: we've been deleted.
+  }
+
+ private:
+  MouseWatcher* mouse_watcher_;
+
+  // A factory that is used to construct a delayed callback to the listener.
+  base::WeakPtrFactory<Observer> notify_listener_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(Observer);
+};
+#else
+class MouseWatcher::Observer : public ui::EventHandler {
+ public:
+  explicit Observer(MouseWatcher* mouse_watcher)
+      : mouse_watcher_(mouse_watcher),
+        notify_listener_factory_(this) {
+    aura::Env::GetInstance()->AddPreTargetHandler(this);
+  }
+
+  virtual ~Observer() {
+    aura::Env::GetInstance()->RemovePreTargetHandler(this);
+  }
+
+  // ui::EventHandler implementation:
+  virtual void OnMouseEvent(ui::MouseEvent* event) OVERRIDE {
+    switch (event->type()) {
+      case ui::ET_MOUSE_MOVED:
+      case ui::ET_MOUSE_DRAGGED:
+        HandleMouseEvent(MouseWatcherHost::MOUSE_MOVE);
+        break;
+      case ui::ET_MOUSE_EXITED:
+        HandleMouseEvent(MouseWatcherHost::MOUSE_EXIT);
+        break;
+      default:
+        break;
+    }
+  }
+
+ private:
+  MouseWatcherHost* host() const { return mouse_watcher_->host_.get(); }
+
+  // Called when a mouse event we're interested is seen.
+  void HandleMouseEvent(MouseWatcherHost::MouseEventType event_type) {
+    // It's safe to use last_mouse_location() here as this function is invoked
+    // during event dispatching.
+    if (!host()->Contains(aura::Env::GetInstance()->last_mouse_location(),
+                          event_type)) {
+      // Mouse moved outside the host's zone, start a timer to notify the
+      // listener.
+      if (!notify_listener_factory_.HasWeakPtrs()) {
         base::MessageLoop::current()->PostDelayedTask(
             FROM_HERE,
             base::Bind(&Observer::NotifyListener,
                        notify_listener_factory_.GetWeakPtr()),
             event_type == MouseWatcherHost::MOUSE_MOVE
                 ? base::TimeDelta::FromMilliseconds(kNotifyListenerTimeMs)
                 : mouse_watcher_->notify_on_exit_time_);
       }
     } else {
       // Mouse moved quickly out of the host and then into it again, so cancel
       // the timer.
       notify_listener_factory_.InvalidateWeakPtrs();
     }
   }
 
   void NotifyListener() {
     mouse_watcher_->NotifyListener();
     // WARNING: we've been deleted.
   }
 
  private:
   MouseWatcher* mouse_watcher_;
 
   // A factory that is used to construct a delayed callback to the listener.
   base::WeakPtrFactory<Observer> notify_listener_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(Observer);
 };
+#endif
 
 MouseWatcherListener::~MouseWatcherListener() {
 }
 
 MouseWatcherHost::~MouseWatcherHost() {
 }
 
 MouseWatcher::MouseWatcher(MouseWatcherHost* host,
                            MouseWatcherListener* listener)
     : host_(host),
@@ skipping 13 matching lines @@
 void MouseWatcher::Stop() {
   observer_.reset(NULL);
 }
 
 void MouseWatcher::NotifyListener() {
   observer_.reset(NULL);
   listener_->MouseMovedOutOfHost();
 }
 
 }  // namespace views