ui/events/event_source.cc

   1 // Copyright 2013 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 #include "ui/events/event_source.h"
   6
   7 #include <algorithm>
   8
   9 #include "ui/events/event_processor.h"
  10 #include "ui/events/event_rewriter.h"
  11
  12 namespace ui {
  13
  14 EventSource::EventSource() {}
  15
  16 EventSource::~EventSource() {}
  17
  18 void EventSource::AddEventRewriter(EventRewriter* rewriter) {
  19   DCHECK(rewriter);
  20   DCHECK(rewriter_list_.end() ==
  21          std::find(rewriter_list_.begin(), rewriter_list_.end(), rewriter));
  22   rewriter_list_.push_back(rewriter);
  23 }
  24
  25 void EventSource::RemoveEventRewriter(EventRewriter* rewriter) {
  26   EventRewriterList::iterator find =
  27       std::find(rewriter_list_.begin(), rewriter_list_.end(), rewriter);
  28   if (find != rewriter_list_.end())
  29     rewriter_list_.erase(find);
  30 }
  31
  32 EventDispatchDetails EventSource::SendEventToProcessor(Event* event) {
  33   scoped_ptr<Event> rewritten_event;
  34   EventRewriteStatus status = EVENT_REWRITE_CONTINUE;
  35   EventRewriterList::const_iterator it = rewriter_list_.begin(),
  36                                     end = rewriter_list_.end();
  37   for (; it != end; ++it) {
  38     status = (*it)->RewriteEvent(*event, &rewritten_event);
  39     if (status == EVENT_REWRITE_DISCARD) {
  40       CHECK(!rewritten_event);
  41       return EventDispatchDetails();
  42     }
  43     if (status == EVENT_REWRITE_CONTINUE) {
  44       CHECK(!rewritten_event);
  45       continue;
  46     }
  47     break;
  48   }
  49   CHECK((it == end && !rewritten_event) || rewritten_event);
  50   EventDispatchDetails details =
  51       DeliverEventToProcessor(rewritten_event ? rewritten_event.get() : event);
  52   if (details.dispatcher_destroyed)
  53     return details;
  54
  55   while (status == EVENT_REWRITE_DISPATCH_ANOTHER) {
  56     scoped_ptr<Event> new_event;
  57     status = (*it)->NextDispatchEvent(*rewritten_event, &new_event);
  58     if (status == EVENT_REWRITE_DISCARD)
  59       return EventDispatchDetails();
  60     CHECK_NE(EVENT_REWRITE_CONTINUE, status);
  61     CHECK(new_event);
  62     details = DeliverEventToProcessor(new_event.get());
  63     if (details.dispatcher_destroyed)
  64       return details;
  65     rewritten_event.reset(new_event.release());
  66   }
  67   return EventDispatchDetails();
  68 }
  69
  70 EventDispatchDetails EventSource::DeliverEventToProcessor(Event* event) {
  71   EventProcessor* processor = GetEventProcessor();
  72   CHECK(processor);
  73   return processor->OnEventFromSource(event);
  74 }
  75
  76 }  // namespace ui