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