| // 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 "ui/base/dragdrop/drop_target_win.h" |
| |
| #include <shlobj.h> |
| |
| #include "base/logging.h" |
| |
| namespace ui { |
| |
| IDropTargetHelper* DropTargetWin::cached_drop_target_helper_ = nullptr; |
| |
| DropTargetWin::DropTargetWin() : hwnd_(nullptr), ref_count_(0) {} |
| |
| DropTargetWin::~DropTargetWin() {} |
| |
| void DropTargetWin::Init(HWND hwnd) { |
| DCHECK(!hwnd_); |
| DCHECK(hwnd); |
| HRESULT result = RegisterDragDrop(hwnd, this); |
| DCHECK(SUCCEEDED(result)); |
| } |
| |
| |
| // static |
| IDropTargetHelper* DropTargetWin::DropHelper() { |
| if (!cached_drop_target_helper_) { |
| CoCreateInstance(CLSID_DragDropHelper, 0, CLSCTX_INPROC_SERVER, |
| IID_IDropTargetHelper, |
| reinterpret_cast<void**>(&cached_drop_target_helper_)); |
| } |
| return cached_drop_target_helper_; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| // DropTargetWin, IDropTarget implementation: |
| |
| HRESULT DropTargetWin::DragEnter(IDataObject* data_object, |
| DWORD key_state, |
| POINTL cursor_position, |
| DWORD* effect) { |
| // Tell the helper that we entered so it can update the drag image. |
| IDropTargetHelper* drop_helper = DropHelper(); |
| if (drop_helper) { |
| drop_helper->DragEnter(GetHWND(), data_object, |
| reinterpret_cast<POINT*>(&cursor_position), *effect); |
| } |
| |
| current_data_object_ = data_object; |
| POINT screen_pt = { cursor_position.x, cursor_position.y }; |
| *effect = |
| OnDragEnter(current_data_object_.get(), key_state, screen_pt, *effect); |
| return S_OK; |
| } |
| |
| HRESULT DropTargetWin::DragOver(DWORD key_state, |
| POINTL cursor_position, |
| DWORD* effect) { |
| // Tell the helper that we moved over it so it can update the drag image. |
| IDropTargetHelper* drop_helper = DropHelper(); |
| if (drop_helper) |
| drop_helper->DragOver(reinterpret_cast<POINT*>(&cursor_position), *effect); |
| |
| POINT screen_pt = { cursor_position.x, cursor_position.y }; |
| *effect = |
| OnDragOver(current_data_object_.get(), key_state, screen_pt, *effect); |
| return S_OK; |
| } |
| |
| HRESULT DropTargetWin::DragLeave() { |
| // Tell the helper that we moved out of it so it can update the drag image. |
| IDropTargetHelper* drop_helper = DropHelper(); |
| if (drop_helper) |
| drop_helper->DragLeave(); |
| |
| OnDragLeave(current_data_object_.get()); |
| |
| current_data_object_ = nullptr; |
| return S_OK; |
| } |
| |
| HRESULT DropTargetWin::Drop(IDataObject* data_object, |
| DWORD key_state, |
| POINTL cursor_position, |
| DWORD* effect) { |
| // Tell the helper that we dropped onto it so it can update the drag image. |
| IDropTargetHelper* drop_helper = DropHelper(); |
| if (drop_helper) { |
| drop_helper->Drop(current_data_object_.get(), |
| reinterpret_cast<POINT*>(&cursor_position), *effect); |
| } |
| |
| POINT screen_pt = { cursor_position.x, cursor_position.y }; |
| *effect = OnDrop(current_data_object_.get(), key_state, screen_pt, *effect); |
| return S_OK; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| // DropTargetWin, IUnknown implementation: |
| |
| HRESULT DropTargetWin::QueryInterface(const IID& iid, void** object) { |
| *object = nullptr; |
| if (IsEqualIID(iid, IID_IUnknown) || IsEqualIID(iid, IID_IDropTarget)) { |
| *object = this; |
| } else { |
| return E_NOINTERFACE; |
| } |
| AddRef(); |
| return S_OK; |
| } |
| |
| ULONG DropTargetWin::AddRef() { |
| return ++ref_count_; |
| } |
| |
| ULONG DropTargetWin::Release() { |
| if (--ref_count_ == 0) { |
| delete this; |
| return 0U; |
| } |
| return ref_count_; |
| } |
| |
| DWORD DropTargetWin::OnDragEnter(IDataObject* data_object, |
| DWORD key_state, |
| POINT cursor_position, |
| DWORD effect) { |
| return DROPEFFECT_NONE; |
| } |
| |
| DWORD DropTargetWin::OnDragOver(IDataObject* data_object, |
| DWORD key_state, |
| POINT cursor_position, |
| DWORD effect) { |
| return DROPEFFECT_NONE; |
| } |
| |
| void DropTargetWin::OnDragLeave(IDataObject* data_object) { |
| } |
| |
| DWORD DropTargetWin::OnDrop(IDataObject* data_object, |
| DWORD key_state, |
| POINT cursor_position, |
| DWORD effect) { |
| return DROPEFFECT_NONE; |
| } |
| |
| } // namespace ui |