| // 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 UI_EVENTS_PLATFORM_PLATFORM_EVENT_DISPATCHER_H_ |
| #define UI_EVENTS_PLATFORM_PLATFORM_EVENT_DISPATCHER_H_ |
| |
| #include "base/basictypes.h" |
| #include "ui/events/events_export.h" |
| #include "ui/events/platform/platform_event_types.h" |
| |
| namespace ui { |
| |
| // See documentation for |PlatformEventDispatcher::DispatchEvent()| for |
| // explanation of the meaning of the flags. |
| enum PostDispatchAction { |
| POST_DISPATCH_NONE = 0x0, |
| POST_DISPATCH_PERFORM_DEFAULT = 0x1, |
| POST_DISPATCH_STOP_PROPAGATION = 0x2, |
| }; |
| |
| // PlatformEventDispatcher receives events from a PlatformEventSource and |
| // dispatches them. |
| class EVENTS_EXPORT PlatformEventDispatcher { |
| public: |
| // Returns whether this dispatcher wants to dispatch |event|. |
| virtual bool CanDispatchEvent(const PlatformEvent& event) = 0; |
| |
| // Dispatches |event|. If this is not the default dispatcher, then the |
| // dispatcher can request that the default dispatcher gets a chance to |
| // dispatch the event by setting POST_DISPATCH_PERFORM_DEFAULT to the return |
| // value. If the dispatcher has processed the event, and no other dispatcher |
| // should be allowed to dispatch the event, then the dispatcher should set |
| // POST_DISPATCH_STOP_PROPAGATION flag on the return value. |
| virtual uint32_t DispatchEvent(const PlatformEvent& event) = 0; |
| |
| protected: |
| virtual ~PlatformEventDispatcher() {} |
| }; |
| |
| } // namespace ui |
| |
| #endif // UI_EVENTS_PLATFORM_PLATFORM_EVENT_DISPATCHER_H_ |