Get drag and drop working for win aura.

ui/views/widget/desktop_aura/desktop_root_window_host_win.cc

 // Copyright (c) 2012 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/views/widget/desktop_aura/desktop_root_window_host_win.h"
 
 #include "third_party/skia/include/core/SkPath.h"
 #include "third_party/skia/include/core/SkRegion.h"
 #include "ui/aura/client/aura_constants.h"
 #include "ui/aura/client/default_capture_client.h"
 #include "ui/aura/focus_manager.h"
 #include "ui/aura/root_window.h"
 #include "ui/aura/ui_controls_aura.h"
 #include "ui/aura/window_property.h"
 #include "ui/base/cursor/cursor_loader_win.h"
 #include "ui/base/win/shell.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/gfx/path_win.h"
 #include "ui/native_theme/native_theme_aura.h"
 #include "ui/native_theme/native_theme_win.h"
 #include "ui/ui_controls/ui_controls.h"
 #include "ui/views/corewm/compound_event_filter.h"
 #include "ui/views/corewm/input_method_event_filter.h"
 #include "ui/views/ime/input_method_win.h"
 #include "ui/views/widget/desktop_aura/desktop_activation_client.h"
 #include "ui/views/widget/desktop_aura/desktop_cursor_client.h"
 #include "ui/views/widget/desktop_aura/desktop_dispatcher_client.h"
+#include "ui/views/widget/desktop_aura/desktop_drag_drop_client_win.h"
 #include "ui/views/widget/desktop_aura/desktop_native_widget_aura.h"
 #include "ui/views/widget/desktop_aura/desktop_screen_position_client.h"
+#include "ui/views/widget/drop_target_win.h"
+#include "ui/views/widget/root_view.h"
 #include "ui/views/widget/widget_delegate.h"
 #include "ui/views/widget/widget_hwnd_utils.h"
 #include "ui/views/win/fullscreen_handler.h"
 #include "ui/views/win/hwnd_message_handler.h"
 #include "ui/views/window/native_frame_view.h"
 
 namespace views {
 
 DEFINE_WINDOW_PROPERTY_KEY(aura::Window*, kContentWindowForRootWindow, NULL);
 
@@ skipping 82 matching lines @@
 
   activation_client_.reset(new DesktopActivationClient(root_window_));
 
   dispatcher_client_.reset(new DesktopDispatcherClient);
   aura::client::SetDispatcherClient(root_window_,
                                     dispatcher_client_.get());
 
   cursor_client_.reset(new DesktopCursorClient(root_window_));
   aura::client::SetCursorClient(root_window_, cursor_client_.get());
 
-
   position_client_.reset(new DesktopScreenPositionClient());
   aura::client::SetScreenPositionClient(root_window_,
                                         position_client_.get());
 
+  drag_drop_client_.reset(new DesktopDragDropClientWin);
+  aura::client::SetDragDropClient(root_window_, drag_drop_client_.get());
+
   // CEF sets focus to the window the user clicks down on.
   // TODO(beng): see if we can't do this some other way. CEF seems a heavy-
   //             handed way of accomplishing focus.
   root_window_event_filter_ = new views::corewm::CompoundEventFilter;
   root_window_->SetEventFilter(root_window_event_filter_);
 
   input_method_filter_.reset(new views::corewm::InputMethodEventFilter);
   input_method_filter_->SetInputMethodPropertyInRootWindow(root_window_);
   root_window_event_filter_->AddHandler(input_method_filter_.get());
 
@@ skipping 456 matching lines @@
 
 void DesktopRootWindowHostWin::HandleAccelerator(
     const ui::Accelerator& accelerator) {
   GetWidget()->GetFocusManager()->ProcessAccelerator(accelerator);
 }
 
 void DesktopRootWindowHostWin::HandleCreate() {
   // TODO(beng): moar
   NOTIMPLEMENTED();
 
+  drop_target_ = new DropTargetWin(
+      static_cast<internal::RootView*>(GetWidget()->GetRootView()),
+      GetHWND());
+
   native_widget_delegate_->OnNativeWidgetCreated();
 
   // 1. Window property association
   // 2. MouseWheel.
-  // 3. Drop target.
-  // 4. Tooltip Manager.
+  // 3. Tooltip Manager.
 }
 
 void DesktopRootWindowHostWin::HandleDestroying() {
+  if (drop_target_.get()) {

[Ben Goodger (Google), 2012/12/06 18:22:28]

but can't we just call through to the DDC here then?

[jam, 2012/12/06 18:48:02]

ok, done

+    RevokeDragDrop(GetHWND());
+    drop_target_ = NULL;
+  }
   native_widget_delegate_->OnNativeWidgetDestroying();
 }
 
 void DesktopRootWindowHostWin::HandleDestroyed() {
   root_window_event_filter_->RemoveHandler(input_method_filter_.get());
   desktop_native_widget_aura_->OnHostClosed();
 }
 
 bool DesktopRootWindowHostWin::HandleInitialFocus() {
   return GetWidget()->SetInitialFocus();
@@ skipping 155 matching lines @@
 DesktopRootWindowHost* DesktopRootWindowHost::Create(
     internal::NativeWidgetDelegate* native_widget_delegate,
     DesktopNativeWidgetAura* desktop_native_widget_aura,
     const gfx::Rect& initial_bounds) {
   return new DesktopRootWindowHostWin(native_widget_delegate,
                                       desktop_native_widget_aura,
                                       initial_bounds);
 }
 
 }  // namespace views