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diff --git a/ui/views/drag_controller.h b/ui/views/drag_controller.h
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+++ b/ui/views/drag_controller.h
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+// 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.
+
+#ifndef UI_VIEWS_DRAG_CONTROLLER_H_
+#define UI_VIEWS_DRAG_CONTROLLER_H_
+#pragma once
+
+#include "views/views_export.h"
+
+namespace gfx {
+class Point;
+}
+
+namespace ui {
+class OSExchangeData;
+}
+
+namespace views {
+class View;
+
+// DragController is responsible for writing drag data for a view, as well as
+// supplying the supported drag operations. Use DragController if you don't
+// want to subclass.
+class VIEWS_EXPORT DragController {
+ public:
+  // Writes the data for the drag.
+  virtual void WriteDragDataForView(View* sender,
+                                    const gfx::Point& press_pt,
+                                    ui::OSExchangeData* data) = 0;
+
+  // Returns the supported drag operations (see DragDropTypes for possible
+  // values). A drag is only started if this returns a non-zero value.
+  virtual int GetDragOperationsForView(View* sender,
+                                       const gfx::Point& p) = 0;
+
+  // Returns true if a drag operation can be started.
+  // |press_pt| represents the coordinates where the mouse was initially
+  // pressed down. |p| is the current mouse coordinates.
+  virtual bool CanStartDragForView(View* sender,
+                                   const gfx::Point& press_pt,
+                                   const gfx::Point& p) = 0;
+
+ protected:
+  virtual ~DragController() {}
+};
+
+}  // namespace views
+
+#endif  // UI_VIEWS_DRAG_CONTROLLER_H_