src/ui/aura/window_targeter.cc

   1 // Copyright (c) 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/aura/window_targeter.h"
   6
   7 #include "ui/aura/client/capture_client.h"
   8 #include "ui/aura/client/event_client.h"
   9 #include "ui/aura/client/focus_client.h"
  10 #include "ui/aura/window.h"
  11 #include "ui/aura/window_delegate.h"
  12 #include "ui/aura/window_event_dispatcher.h"
  13 #include "ui/aura/window_tree_host.h"
  14 #include "ui/events/event_target.h"
  15
  16 namespace aura {
  17
  18 namespace {
  19
  20 bool IsLocatedEvent(const ui::Event& event) {
  21   return event.IsMouseEvent() || event.IsTouchEvent() ||
  22          event.IsScrollEvent() || event.IsGestureEvent();
  23 }
  24
  25 }  // namespace
  26
  27 WindowTargeter::WindowTargeter() {}
  28 WindowTargeter::~WindowTargeter() {}
  29
  30 ui::EventTarget* WindowTargeter::FindTargetForEvent(ui::EventTarget* root,
  31                                                     ui::Event* event) {
  32   Window* window = static_cast<Window*>(root);
  33   Window* target = event->IsKeyEvent() ?
  34       FindTargetForKeyEvent(window, *static_cast<ui::KeyEvent*>(event)) :
  35       static_cast<Window*>(EventTargeter::FindTargetForEvent(root, event));
  36   if (target && !window->parent() && !window->Contains(target)) {
  37     // |window| is the root window, but |target| is not a descendent of
  38     // |window|. So do not allow dispatching from here. Instead, dispatch the
  39     // event through the WindowEventDispatcher that owns |target|.
  40     aura::Window* new_root = target->GetRootWindow();
  41     if (IsLocatedEvent(*event)) {
  42       // The event has been transformed to be in |target|'s coordinate system.
  43       // But dispatching the event through the EventProcessor requires the event
  44       // to be in the host's coordinate system. So, convert the event to be in
  45       // the root's coordinate space, and then to the host's coordinate space by
  46       // applying the host's transform.
  47       ui::LocatedEvent* located_event = static_cast<ui::LocatedEvent*>(event);
  48       located_event->ConvertLocationToTarget(target, new_root);
  49       located_event->UpdateForRootTransform(
  50           new_root->GetHost()->GetRootTransform());
  51     }
  52     ignore_result(
  53         new_root->GetHost()->event_processor()->OnEventFromSource(event));
  54
  55     target = NULL;
  56   }
  57   return target;
  58 }
  59
  60 bool WindowTargeter::SubtreeCanAcceptEvent(
  61     ui::EventTarget* target,
  62     const ui::LocatedEvent& event) const {
  63   aura::Window* window = static_cast<aura::Window*>(target);
  64   if (!window->IsVisible())
  65     return false;
  66   if (window->ignore_events())
  67     return false;
  68   client::EventClient* client = client::GetEventClient(window->GetRootWindow());
  69   if (client && !client->CanProcessEventsWithinSubtree(window))
  70     return false;
  71
  72   Window* parent = window->parent();
  73   if (parent && parent->delegate_ && !parent->delegate_->
  74       ShouldDescendIntoChildForEventHandling(window, event.location())) {
  75     return false;
  76   }
  77   return true;
  78 }
  79
  80 bool WindowTargeter::EventLocationInsideBounds(
  81     ui::EventTarget* target,
  82     const ui::LocatedEvent& event) const {
  83   aura::Window* window = static_cast<aura::Window*>(target);
  84   gfx::Point point = event.location();
  85   if (window->parent())
  86     aura::Window::ConvertPointToTarget(window->parent(), window, &point);
  87   return gfx::Rect(window->bounds().size()).Contains(point);
  88 }
  89
  90 ui::EventTarget* WindowTargeter::FindTargetForLocatedEvent(
  91     ui::EventTarget* root,
  92     ui::LocatedEvent* event) {
  93   Window* window = static_cast<Window*>(root);
  94   if (!window->parent()) {
  95     Window* target = FindTargetInRootWindow(window, *event);
  96     if (target) {
  97       window->ConvertEventToTarget(target, event);
  98       return target;
  99     }
 100   }
 101   return EventTargeter::FindTargetForLocatedEvent(root, event);
 102 }
 103
 104 Window* WindowTargeter::FindTargetForKeyEvent(Window* window,
 105                                               const ui::KeyEvent& key) {
 106   Window* root_window = window->GetRootWindow();
 107   client::FocusClient* focus_client = client::GetFocusClient(root_window);
 108   Window* focused_window = focus_client->GetFocusedWindow();
 109   if (!focused_window)
 110     return window;
 111
 112   client::EventClient* event_client = client::GetEventClient(root_window);
 113   if (event_client &&
 114       !event_client->CanProcessEventsWithinSubtree(focused_window)) {
 115     focus_client->FocusWindow(NULL);
 116     return NULL;
 117   }
 118   return focused_window ? focused_window : window;
 119 }
 120
 121 Window* WindowTargeter::FindTargetInRootWindow(Window* root_window,
 122                                                const ui::LocatedEvent& event) {
 123   DCHECK_EQ(root_window, root_window->GetRootWindow());
 124
 125   // Mouse events should be dispatched to the window that processed the
 126   // mouse-press events (if any).
 127   if (event.IsScrollEvent() || event.IsMouseEvent()) {
 128     WindowEventDispatcher* dispatcher = root_window->GetHost()->dispatcher();
 129     if (dispatcher->mouse_pressed_handler())
 130       return dispatcher->mouse_pressed_handler();
 131   }
 132
 133   // All events should be directed towards the capture window (if any).
 134   Window* capture_window = client::GetCaptureWindow(root_window);
 135   if (capture_window)
 136     return capture_window;
 137
 138   if (event.IsTouchEvent()) {
 139     // Query the gesture-recognizer to find targets for touch events.
 140     const ui::TouchEvent& touch = static_cast<const ui::TouchEvent&>(event);
 141     ui::GestureConsumer* consumer =
 142         ui::GestureRecognizer::Get()->GetTouchLockedTarget(touch);
 143     if (consumer)
 144       return static_cast<Window*>(consumer);
 145     consumer =
 146         ui::GestureRecognizer::Get()->GetTargetForLocation(
 147             event.location(), touch.source_device_id());
 148     if (consumer)
 149       return static_cast<Window*>(consumer);
 150
 151     // If the initial touch is outside the root window, target the root.
 152     if (!root_window->bounds().Contains(event.location()))
 153       return root_window;
 154   }
 155
 156   return NULL;
 157 }
 158
 159 }  // namespace aura