Wires up PointerWatcherEventRouter for views aura-mus

ui/views/mus/pointer_watcher_event_router2.h

+// Copyright 2016 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 UI_VIEWS_MUS_POINTER_WATCHER_EVENT_ROUTER2_H_
+#define UI_VIEWS_MUS_POINTER_WATCHER_EVENT_ROUTER2_H_
+
+#include "base/compiler_specific.h"
+#include "base/macros.h"
+#include "base/observer_list.h"
+#include "ui/aura/client/capture_client_observer.h"
+#include "ui/aura/mus/window_tree_client_observer.h"
+#include "ui/views/mus/mus_export.h"
+
+namespace aura {
+class WindowTreeClient;
+namespace client {
+class CaptureClient;
+}
+}
+
+namespace ui {
+class PointerEvent;
+}
+
+namespace views {
+
+class PointerWatcher;
+class PointerWatcherEventRouter2Test;
+
+// PointerWatcherEventRouter2 is responsible for maintaining the list of
+// PointerWatchers and notifying appropriately. It is expected the owner of
+// PointerWatcherEventRouter2 is a WindowTreeClientDelegate and calls
+// OnPointerEventObserved().
+// TODO(sky): Nuke existing PointerWatcherEventRouter and rename this.
+class VIEWS_MUS_EXPORT PointerWatcherEventRouter2
+    : public aura::WindowTreeClientObserver,
+      public aura::client::CaptureClientObserver {
+ public:
+  // Public solely for tests.
+  enum EventTypes {
+    // No PointerWatchers have been added.
+    NONE,
+
+    // Used when the only PointerWatchers added do not want moves.
+    NON_MOVE_EVENTS,
+
+    // Used when at least one PointerWatcher has been added that wants moves.
+    MOVE_EVENTS,
+  };
+
+  explicit PointerWatcherEventRouter2(
+      aura::WindowTreeClient* window_tree_client);
+  ~PointerWatcherEventRouter2() override;
+
+  // Called by WindowTreeClientDelegate to notify PointerWatchers appropriately.
+  void OnPointerEventObserved(const ui::PointerEvent& event,
+                              aura::Window* target);
+
+  void AddPointerWatcher(PointerWatcher* watcher, bool wants_moves);
+  void RemovePointerWatcher(PointerWatcher* watcher);
+
+ private:
+  friend class PointerWatcherEventRouter2Test;
+
+  // Determines EventTypes based on the number and type of PointerWatchers.
+  EventTypes DetermineEventTypes();
+
+  // aura::WindowTreeClientObserver:
+  void OnDidDestroyClient(aura::WindowTreeClient* client) override;
+
+  // aura::client::CaptureClientObserver:
+  void OnCaptureChanged(aura::Window* lost_capture,
+                        aura::Window* gained_capture) override;
+
+  aura::WindowTreeClient* window_tree_client_;
+  // The true parameter to ObserverList indicates the list must be empty on
+  // destruction. Two sets of observers are maintained, one for observers not
+  // needing moves |non_move_watchers_| and |move_watchers_| for those
+  // observers wanting moves too.
+  base::ObserverList<views::PointerWatcher, true> non_move_watchers_;
+  base::ObserverList<views::PointerWatcher, true> move_watchers_;
+
+  EventTypes event_types_ = EventTypes::NONE;
+
+  DISALLOW_COPY_AND_ASSIGN(PointerWatcherEventRouter2);
+};
+
+}  // namespace views
+
+#endif  // UI_VIEWS_MUS_POINTER_WATCHER_EVENT_ROUTER2_H_