Revert "Delete the ViewManager and WindowManager services."

mojo/services/view_manager/cpp/view_observer.h

+// Copyright 2014 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 MOJO_SERVICES_VIEW_MANAGER_CPP_VIEW_OBSERVER_H_
+#define MOJO_SERVICES_VIEW_MANAGER_CPP_VIEW_OBSERVER_H_
+
+#include <vector>
+
+#include "input_events/interfaces/input_events.mojom.h"
+#include "view_manager/cpp/view.h"
+
+namespace mojo {
+
+class View;
+
+// A note on -ing and -ed suffixes:
+//
+// -ing methods are called before changes are applied to the local view model.
+// -ed methods are called after changes are applied to the local view model.
+//
+// If the change originated from another connection to the view manager, it's
+// possible that the change has already been applied to the service-side model
+// prior to being called, so for example in the case of OnViewDestroying(), it's
+// possible the view has already been destroyed on the service side.
+
+class ViewObserver {
+ public:
+  struct TreeChangeParams {
+    TreeChangeParams();
+    View* target;
+    View* old_parent;
+    View* new_parent;
+    View* receiver;
+  };
+
+  virtual void OnTreeChanging(const TreeChangeParams& params) {}
+  virtual void OnTreeChanged(const TreeChangeParams& params) {}
+
+  virtual void OnViewReordering(View* view,
+                                View* relative_view,
+                                OrderDirection direction) {}
+  virtual void OnViewReordered(View* view,
+                               View* relative_view,
+                               OrderDirection direction) {}
+
+  virtual void OnViewDestroying(View* view) {}
+  virtual void OnViewDestroyed(View* view) {}
+
+  virtual void OnViewBoundsChanging(View* view,
+                                    const Rect& old_bounds,
+                                    const Rect& new_bounds) {}
+  virtual void OnViewBoundsChanged(View* view,
+                                   const Rect& old_bounds,
+                                   const Rect& new_bounds) {}
+
+  virtual void OnViewViewportMetricsChanged(View* view,
+                                            const ViewportMetrics& old_bounds,
+                                            const ViewportMetrics& new_bounds) {
+  }
+
+  virtual void OnViewCaptureChanged(View* gained_capture, View* lost_capture) {}
+  virtual void OnViewFocusChanged(View* gained_focus, View* lost_focus) {}
+  virtual void OnViewActivationChanged(View* gained_active, View* lost_active) {
+  }
+
+  virtual void OnViewInputEvent(View* view, const EventPtr& event) {}
+
+  virtual void OnViewVisibilityChanging(View* view) {}
+  virtual void OnViewVisibilityChanged(View* view) {}
+
+  // Invoked when this View's shared properties have changed. This can either
+  // be caused by SetSharedProperty() being called locally, or by us receiving
+  // a mojo message that this property has changed. If this property has been
+  // added, |old_data| is null. If this property was removed, |new_data| is
+  // null.
+  virtual void OnViewSharedPropertyChanged(
+      View* view,
+      const std::string& name,
+      const std::vector<uint8_t>* old_data,
+      const std::vector<uint8_t>* new_data) {}
+
+  // Invoked when SetProperty() or ClearProperty() is called on the window.
+  // |key| is either a WindowProperty<T>* (SetProperty, ClearProperty). Either
+  // way, it can simply be compared for equality with the property
+  // constant. |old| is the old property value, which must be cast to the
+  // appropriate type before use.
+  virtual void OnViewLocalPropertyChanged(View* view,
+                                          const void* key,
+                                          intptr_t old) {}
+
+  virtual void OnViewEmbeddedAppDisconnected(View* view) {}
+
+  // Sent when the drawn state changes. This is only sent for the root nodes
+  // when embedded.
+  virtual void OnViewDrawnChanging(View* view) {}
+  virtual void OnViewDrawnChanged(View* view) {}
+
+ protected:
+  virtual ~ViewObserver() {}
+};
+
+}  // namespace mojo
+
+#endif  // MOJO_SERVICES_VIEW_MANAGER_CPP_VIEW_OBSERVER_H_