| // Copyright (c) 2006-2008 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/drag_utils.h" |
| |
| #include <objidl.h> |
| #include <shlobj.h> |
| #include <shobjidl.h> |
| |
| #include "app/gfx/canvas.h" |
| #include "app/os_exchange_data.h" |
| #include "base/gfx/gdi_util.h" |
| |
| namespace drag_utils { |
| |
| static void SetDragImageOnDataObject(HBITMAP hbitmap, |
| int width, |
| int height, |
| int cursor_offset_x, |
| int cursor_offset_y, |
| IDataObject* data_object) { |
| IDragSourceHelper* helper = NULL; |
| HRESULT rv = CoCreateInstance(CLSID_DragDropHelper, 0, CLSCTX_INPROC_SERVER, |
| IID_IDragSourceHelper, reinterpret_cast<LPVOID*>(&helper)); |
| if (SUCCEEDED(rv)) { |
| SHDRAGIMAGE sdi; |
| sdi.sizeDragImage.cx = width; |
| sdi.sizeDragImage.cy = height; |
| sdi.crColorKey = 0xFFFFFFFF; |
| sdi.hbmpDragImage = hbitmap; |
| sdi.ptOffset.x = cursor_offset_x; |
| sdi.ptOffset.y = cursor_offset_y; |
| helper->InitializeFromBitmap(&sdi, data_object); |
| } |
| }; |
| |
| // Blit the contents of the canvas to a new HBITMAP. It is the caller's |
| // responsibility to release the |bits| buffer. |
| static HBITMAP CreateBitmapFromCanvas(const gfx::Canvas& canvas, |
| int width, |
| int height) { |
| HDC screen_dc = GetDC(NULL); |
| BITMAPINFOHEADER header; |
| gfx::CreateBitmapHeader(width, height, &header); |
| void* bits; |
| HBITMAP bitmap = |
| CreateDIBSection(screen_dc, reinterpret_cast<BITMAPINFO*>(&header), |
| DIB_RGB_COLORS, &bits, NULL, 0); |
| HDC compatible_dc = CreateCompatibleDC(screen_dc); |
| HGDIOBJ old_object = SelectObject(compatible_dc, bitmap); |
| BitBlt(compatible_dc, 0, 0, width, height, |
| canvas.getTopPlatformDevice().getBitmapDC(), |
| 0, 0, SRCCOPY); |
| SelectObject(compatible_dc, old_object); |
| ReleaseDC(NULL, compatible_dc); |
| ReleaseDC(NULL, screen_dc); |
| return bitmap; |
| } |
| |
| void SetDragImageOnDataObject(const gfx::Canvas& canvas, |
| int width, |
| int height, |
| int cursor_x_offset, |
| int cursor_y_offset, |
| OSExchangeData* data_object) { |
| DCHECK(data_object && width > 0 && height > 0); |
| // SetDragImageOnDataObject(HBITMAP) takes ownership of the bitmap. |
| HBITMAP bitmap = CreateBitmapFromCanvas(canvas, width, height); |
| |
| // Attach 'bitmap' to the data_object. |
| SetDragImageOnDataObject(bitmap, width, height, |
| cursor_x_offset, |
| cursor_y_offset, |
| data_object); |
| } |
| |
| } // namespace drag_utils |