Revert "views: Move widget/ directory to ui/views." properly.

Review URL: http://codereview.chromium.org/8562003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@110960 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 156 insertions, 0 deletions

diff --git a/views/widget/drop_helper.cc b/views/widget/drop_helper.cc
new file mode 100644
index 0000000..4e5ce109
--- /dev/null
+++ b/views/widget/drop_helper.cc
@@ -0,0 +1,156 @@
+// Copyright (c) 2011 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 "views/widget/drop_helper.h"
+
+#include "ui/base/dragdrop/drag_drop_types.h"
+#include "views/view.h"
+#include "views/widget/widget.h"
+
+namespace views {
+
+DropHelper::DropHelper(View* root_view)
+    : root_view_(root_view),
+      target_view_(NULL),
+      deepest_view_(NULL) {
+}
+
+DropHelper::~DropHelper() {
+}
+
+void DropHelper::ResetTargetViewIfEquals(View* view) {
+  if (target_view_ == view)
+    target_view_ = NULL;
+  if (deepest_view_ == view)
+    deepest_view_ = NULL;
+}
+
+int DropHelper::OnDragOver(const OSExchangeData& data,
+                           const gfx::Point& root_view_location,
+                           int drag_operation) {
+  View* view = CalculateTargetViewImpl(root_view_location, data, true,
+                                       &deepest_view_);
+
+  if (view != target_view_) {
+    // Target changed notify old drag exited, then new drag entered.
+    NotifyDragExit();
+    target_view_ = view;
+    NotifyDragEntered(data, root_view_location, drag_operation);
+  }
+
+  return NotifyDragOver(data, root_view_location, drag_operation);
+}
+
+void DropHelper::OnDragExit() {
+  NotifyDragExit();
+  deepest_view_ = target_view_ = NULL;
+}
+
+int DropHelper::OnDrop(const OSExchangeData& data,
+                       const gfx::Point& root_view_location,
+                       int drag_operation) {
+  View* drop_view = target_view_;
+  deepest_view_ = target_view_ = NULL;
+  if (!drop_view)
+    return ui::DragDropTypes::DRAG_NONE;
+
+  if (drag_operation == ui::DragDropTypes::DRAG_NONE) {
+    drop_view->OnDragExited();
+    return ui::DragDropTypes::DRAG_NONE;
+  }
+
+  gfx::Point view_location(root_view_location);
+  View* root_view = drop_view->GetWidget()->GetRootView();
+  View::ConvertPointToView(root_view, drop_view, &view_location);
+  DropTargetEvent drop_event(data, view_location.x(), view_location.y(),
+                             drag_operation);
+  return drop_view->OnPerformDrop(drop_event);
+}
+
+View* DropHelper::CalculateTargetView(
+    const gfx::Point& root_view_location,
+    const OSExchangeData& data,
+    bool check_can_drop) {
+  return CalculateTargetViewImpl(root_view_location, data, check_can_drop,
+                                 NULL);
+}
+
+View* DropHelper::CalculateTargetViewImpl(
+    const gfx::Point& root_view_location,
+    const OSExchangeData& data,
+    bool check_can_drop,
+    View** deepest_view) {
+  View* view = root_view_->GetEventHandlerForPoint(root_view_location);
+  if (view == deepest_view_) {
+    // The view the mouse is over hasn't changed; reuse the target.
+    return target_view_;
+  }
+  if (deepest_view)
+    *deepest_view = view;
+  // TODO(sky): for the time being these are separate. Once I port chrome menu
+  // I can switch to the #else implementation and nuke the OS_WIN
+  // implementation.
+#if defined(OS_WIN)
+  // View under mouse changed, which means a new view may want the drop.
+  // Walk the tree, stopping at target_view_ as we know it'll accept the
+  // drop.
+  while (view && view != target_view_ &&
+         (!view->IsEnabled() || !view->CanDrop(data))) {
+    view = view->parent();
+  }
+#else
+  int formats = 0;
+  std::set<OSExchangeData::CustomFormat> custom_formats;
+  while (view && view != target_view_) {
+    if (view->IsEnabled() &&
+        view->GetDropFormats(&formats, &custom_formats) &&
+        data.HasAnyFormat(formats, custom_formats) &&
+        (!check_can_drop || view->CanDrop(data))) {
+      // Found the view.
+      return view;
+    }
+    formats = 0;
+    custom_formats.clear();
+    view = view->parent();
+  }
+#endif
+  return view;
+}
+
+void DropHelper::NotifyDragEntered(const OSExchangeData& data,
+                                   const gfx::Point& root_view_location,
+                                   int drag_operation) {
+  if (!target_view_)
+    return;
+
+  gfx::Point target_view_location(root_view_location);
+  View::ConvertPointToView(root_view_, target_view_, &target_view_location);
+  DropTargetEvent enter_event(data,
+                              target_view_location.x(),
+                              target_view_location.y(),
+                              drag_operation);
+  target_view_->OnDragEntered(enter_event);
+}
+
+int DropHelper::NotifyDragOver(const OSExchangeData& data,
+                               const gfx::Point& root_view_location,
+                               int drag_operation) {
+  if (!target_view_)
+    return ui::DragDropTypes::DRAG_NONE;
+
+  gfx::Point target_view_location(root_view_location);
+  View::ConvertPointToView(root_view_, target_view_, &target_view_location);
+  DropTargetEvent enter_event(data,
+                              target_view_location.x(),
+                              target_view_location.y(),
+                              drag_operation);
+  return target_view_->OnDragUpdated(enter_event);
+}
+
+void DropHelper::NotifyDragExit() {
+  if (target_view_)
+    target_view_->OnDragExited();
+}
+
+}  // namespace views