ash/drag_drop/drag_drop_tracker.cc

   1 // Copyright (c) 2012 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 "ash/drag_drop/drag_drop_tracker.h"
   6
   7 #include "ash/shell.h"
   8 #include "ash/shell_window_ids.h"
   9 #include "ash/wm/coordinate_conversion.h"
  10 #include "ui/aura/client/window_tree_client.h"
  11 #include "ui/aura/window.h"
  12 #include "ui/aura/window_event_dispatcher.h"
  13 #include "ui/events/event.h"
  14 #include "ui/gfx/screen.h"
  15 #include "ui/wm/core/coordinate_conversion.h"
  16 #include "ui/wm/public/activation_delegate.h"
  17
  18 namespace ash {
  19 namespace {
  20
  21 // An activation delegate which disables activating the drag and drop window.
  22 class CaptureWindowActivationDelegate
  23     : public aura::client::ActivationDelegate {
  24  public:
  25   CaptureWindowActivationDelegate() {}
  26   virtual ~CaptureWindowActivationDelegate() {}
  27
  28   // aura::client::ActivationDelegate overrides:
  29   virtual bool ShouldActivate() const OVERRIDE {
  30     return false;
  31   }
  32
  33  private:
  34
  35   DISALLOW_COPY_AND_ASSIGN(CaptureWindowActivationDelegate);
  36 };
  37
  38 // Creates a window for capturing drag events.
  39 aura::Window* CreateCaptureWindow(aura::Window* context_root,
  40                                   aura::WindowDelegate* delegate) {
  41   static CaptureWindowActivationDelegate* activation_delegate_instance = NULL;
  42   if (!activation_delegate_instance)
  43     activation_delegate_instance = new CaptureWindowActivationDelegate;
  44   aura::Window* window = new aura::Window(delegate);
  45   // Set type of window as popup to prevent different window manager codes
  46   // trying to manage this window.
  47   window->SetType(ui::wm::WINDOW_TYPE_POPUP);
  48   window->Init(aura::WINDOW_LAYER_NOT_DRAWN);
  49   aura::client::ParentWindowWithContext(window, context_root, gfx::Rect());
  50   aura::client::SetActivationDelegate(window, activation_delegate_instance);
  51   window->Show();
  52   DCHECK(window->bounds().size().IsEmpty());
  53   return window;
  54 }
  55
  56 }  // namespace
  57
  58 DragDropTracker::DragDropTracker(aura::Window* context_root,
  59                                  aura::WindowDelegate* delegate)
  60     : capture_window_(CreateCaptureWindow(context_root, delegate)) {
  61 }
  62
  63 DragDropTracker::~DragDropTracker()  {
  64   capture_window_->ReleaseCapture();
  65 }
  66
  67 void DragDropTracker::TakeCapture() {
  68   capture_window_->SetCapture();
  69 }
  70
  71 aura::Window* DragDropTracker::GetTarget(const ui::LocatedEvent& event) {
  72   DCHECK(capture_window_.get());
  73   gfx::Point location_in_screen = event.location();
  74   ::wm::ConvertPointToScreen(capture_window_.get(), &location_in_screen);
  75   aura::Window* root_window_at_point =
  76       wm::GetRootWindowAt(location_in_screen);
  77   gfx::Point location_in_root = location_in_screen;
  78   ::wm::ConvertPointFromScreen(root_window_at_point, &location_in_root);
  79   return root_window_at_point->GetEventHandlerForPoint(location_in_root);
  80 }
  81
  82 ui::LocatedEvent* DragDropTracker::ConvertEvent(
  83     aura::Window* target,
  84     const ui::LocatedEvent& event) {
  85   DCHECK(capture_window_.get());
  86   gfx::Point target_location = event.location();
  87   aura::Window::ConvertPointToTarget(capture_window_.get(), target,
  88                                      &target_location);
  89   gfx::Point location_in_screen = event.location();
  90   ::wm::ConvertPointToScreen(capture_window_.get(), &location_in_screen);
  91   gfx::Point target_root_location = event.root_location();
  92   aura::Window::ConvertPointToTarget(
  93       capture_window_->GetRootWindow(),
  94       ash::wm::GetRootWindowAt(location_in_screen),
  95       &target_root_location);
  96   return new ui::MouseEvent(event.type(),
  97                             target_location,
  98                             target_root_location,
  99                             event.flags(),
 100                             static_cast<const ui::MouseEvent&>(event).
 101                                 changed_button_flags());
 102 }
 103
 104 }  // namespace ash