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// Copyright (c) 2013 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.
#include "ui/events/event_targeter.h"
#include "ui/events/event.h"
#include "ui/events/event_target.h"
#include "ui/events/event_target_iterator.h"
namespace ui {
EventTargeter::~EventTargeter() {
}
EventTarget* EventTargeter::FindTargetForEvent(EventTarget* root,
Event* event) {
if (event->IsMouseEvent() ||
event->IsScrollEvent() ||
event->IsTouchEvent() ||
event->IsGestureEvent()) {
return FindTargetForLocatedEvent(root,
static_cast<LocatedEvent*>(event));
}
return root;
}
EventTarget* EventTargeter::FindTargetForLocatedEvent(EventTarget* root,
LocatedEvent* event) {
scoped_ptr<EventTargetIterator> iter = root->GetChildIterator();
if (iter) {
EventTarget* target = root;
for (EventTarget* child = iter->GetNextTarget(); child;
child = iter->GetNextTarget()) {
EventTargeter* targeter = child->GetEventTargeter();
if (!targeter)
targeter = this;
if (!targeter->SubtreeShouldBeExploredForEvent(child, *event))
continue;
target->ConvertEventToTarget(child, event);
target = child;
EventTarget* child_target = targeter ?
targeter->FindTargetForLocatedEvent(child, event) :
FindTargetForLocatedEvent(child, event);
if (child_target)
return child_target;
}
target->ConvertEventToTarget(root, event);
}
return root->CanAcceptEvent(*event) ? root : NULL;
}
bool EventTargeter::SubtreeShouldBeExploredForEvent(EventTarget* target,
const LocatedEvent& event) {
return SubtreeCanAcceptEvent(target, event) &&
EventLocationInsideBounds(target, event);
}
EventTarget* EventTargeter::FindNextBestTarget(EventTarget* previous_target,
Event* event) {
return NULL;
}
bool EventTargeter::SubtreeCanAcceptEvent(EventTarget* target,
const LocatedEvent& event) const {
return true;
}
bool EventTargeter::EventLocationInsideBounds(EventTarget* target,
const LocatedEvent& event) const {
return true;
}
} // namespace ui
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