ui/events/ozone/events_ozone.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef UI_EVENTS_OZONE_EVENTS_OZONE_H_
   6 #define UI_EVENTS_OZONE_EVENTS_OZONE_H_
   7
   8 #include "base/callback.h"
   9 #include "base/event_types.h"
  10 #include "ui/events/events_export.h"
  11
  12 namespace ui {
  13
  14 class Event;
  15
  16 // Wrap a "native" ui::Event in another ui::Event & dispatch it.
  17 //
  18 // This is really unfortunate, but exists for two reasons:
  19 //
  20 //   1. Some of the ui::Event constructors depend on global state that
  21 //   is only used when building from a "native" event. For example:
  22 //   last_click_event_ is used when constructing MouseEvent from
  23 //   NativeEvent to determine click count.
  24 //
  25 //   2. Events contain a reference to a "native event", which some code
  26 //   depends on. The ui::Event might get mutated during dispatch, but
  27 //   the native event won't. Some code depends on the fact that the
  28 //   "native" version of the event is unmodified.
  29 //
  30 // We are trying to fix both of these issues, but in the meantime we
  31 // define NativeEvent == ui::Event.
  32 //
  33 EVENTS_EXPORT void DispatchEventFromNativeUiEvent(
  34     const base::NativeEvent& native_event,
  35     base::Callback<void(ui::Event*)> callback);
  36
  37 }  // namespace ui
  38
  39 #endif  // UI_EVENTS_OZONE_EVENTS_OZONE_H_