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 #ifndef UI_WM_PUBLIC_DRAG_DROP_DELEGATE_H_ 6 #define UI_WM_PUBLIC_DRAG_DROP_DELEGATE_H_ 7 8 #include "ui/aura/aura_export.h" 9 10 namespace ui { 11 class DropTargetEvent; 12 } 13 14 namespace aura { 15 class Window; 16 namespace client { 17 18 // Delegate interface for drag and drop actions on aura::Window. 19 class AURA_EXPORT DragDropDelegate { 20 public: 21 // OnDragEntered is invoked when the mouse enters this window during a drag & 22 // drop session. This is immediately followed by an invocation of 23 // OnDragUpdated, and eventually one of OnDragExited or OnPerformDrop. 24 virtual void OnDragEntered(const ui::DropTargetEvent& event) = 0; 25 26 // Invoked during a drag and drop session while the mouse is over the window. 27 // This should return a bitmask of the DragDropTypes::DragOperation supported 28 // based on the location of the event. Return 0 to indicate the drop should 29 // not be accepted. 30 virtual int OnDragUpdated(const ui::DropTargetEvent& event) = 0; 31 32 // Invoked during a drag and drop session when the mouse exits the window, or 33 // when the drag session was canceled and the mouse was over the window. 34 virtual void OnDragExited() = 0; 35 36 // Invoked during a drag and drop session when OnDragUpdated returns a valid 37 // operation and the user release the mouse. 38 virtual int OnPerformDrop(const ui::DropTargetEvent& event) = 0; 39 40 protected: ~DragDropDelegate()41 virtual ~DragDropDelegate() {} 42 }; 43 44 AURA_EXPORT void SetDragDropDelegate(Window* window, 45 DragDropDelegate* delegate); 46 AURA_EXPORT DragDropDelegate* GetDragDropDelegate(Window* window); 47 48 } // namespace client 49 } // namespace aura 50 51 #endif // UI_WM_PUBLIC_DRAG_DROP_DELEGATE_H_ 52