// 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_QUIT_LOOP = 0x1, POST_DISPATCH_PERFORM_DEFAULT = 0x2, POST_DISPATCH_STOP_PROPAGATION = 0x4, }; // 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 a nested message-loop is active, then the dispatcher can signal // that the nested message-loop should be terminated by setting // POST_DISPATCH_QUIT_LOOP flag on 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_