ui/views/view_targeter.cc

   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 #include "ui/views/view_targeter.h"
   6
   7 #include "ui/events/event_target.h"
   8 #include "ui/views/focus/focus_manager.h"
   9 #include "ui/views/view.h"
  10 #include "ui/views/view_targeter_delegate.h"
  11
  12 namespace views {
  13
  14 ViewTargeter::ViewTargeter(ViewTargeterDelegate* delegate)
  15     : delegate_(delegate) {
  16   DCHECK(delegate_);
  17 }
  18
  19 ViewTargeter::~ViewTargeter() {}
  20
  21 bool ViewTargeter::DoesIntersectRect(const View* target,
  22                                      const gfx::Rect& rect) const {
  23   return delegate_->DoesIntersectRect(target, rect);
  24 }
  25
  26 View* ViewTargeter::TargetForRect(View* root, const gfx::Rect& rect) const {
  27   return delegate_->TargetForRect(root, rect);
  28 }
  29
  30 ui::EventTarget* ViewTargeter::FindTargetForEvent(ui::EventTarget* root,
  31                                                   ui::Event* event) {
  32   View* view = static_cast<View*>(root);
  33
  34   if (event->IsKeyEvent())
  35     return FindTargetForKeyEvent(view, *static_cast<ui::KeyEvent*>(event));
  36
  37   if (event->IsScrollEvent()) {
  38     return FindTargetForScrollEvent(view,
  39                                     *static_cast<ui::ScrollEvent*>(event));
  40   }
  41
  42   if (event->IsGestureEvent())
  43     return FindTargetForGestureEvent(view, *(event->AsGestureEvent()));
  44
  45   NOTREACHED() << "ViewTargeter does not yet support this event type.";
  46   return NULL;
  47 }
  48
  49 ui::EventTarget* ViewTargeter::FindNextBestTarget(
  50     ui::EventTarget* previous_target,
  51     ui::Event* event) {
  52   if (!previous_target)
  53     return NULL;
  54
  55   if (event->IsGestureEvent()) {
  56     return FindNextBestTargetForGestureEvent(previous_target,
  57                                              *(event->AsGestureEvent()));
  58   }
  59
  60   return previous_target->GetParentTarget();
  61 }
  62
  63 bool ViewTargeter::SubtreeCanAcceptEvent(
  64     ui::EventTarget* target,
  65     const ui::LocatedEvent& event) const {
  66   NOTREACHED();
  67   return false;
  68 }
  69
  70 bool ViewTargeter::EventLocationInsideBounds(
  71     ui::EventTarget* target,
  72     const ui::LocatedEvent& event) const {
  73   NOTREACHED();
  74   return false;
  75 }
  76
  77 View* ViewTargeter::FindTargetForKeyEvent(View* root, const ui::KeyEvent& key) {
  78   if (root->GetFocusManager())
  79     return root->GetFocusManager()->GetFocusedView();
  80   return NULL;
  81 }
  82
  83 View* ViewTargeter::FindTargetForScrollEvent(View* root,
  84                                              const ui::ScrollEvent& scroll) {
  85   gfx::Rect rect(scroll.location(), gfx::Size(1, 1));
  86   return root->GetEffectiveViewTargeter()->TargetForRect(root, rect);
  87 }
  88
  89 View* ViewTargeter::FindTargetForGestureEvent(View* root,
  90                                               const ui::GestureEvent& gesture) {
  91   // TODO(tdanderson): The only code path that performs targeting for gestures
  92   //                   uses the ViewTargeter installed on the RootView (i.e.,
  93   //                   a RootViewTargeter). Provide a default implementation
  94   //                   here if we need to be able to perform gesture targeting
  95   //                   starting at an arbitrary node in a Views tree.
  96   NOTREACHED();
  97   return NULL;
  98 }
  99
 100 ui::EventTarget* ViewTargeter::FindNextBestTargetForGestureEvent(
 101     ui::EventTarget* previous_target,
 102     const ui::GestureEvent& gesture) {
 103   NOTREACHED();
 104   return NULL;
 105 }
 106
 107 }  // namespace views