blob: 9fedd4202a34ac8e32614fd9de5b9d15a07b8407 [file] [log] [blame]
// Copyright (c) 2012 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/drag_utils.h"
#include <objidl.h>
#include <shlobj.h>
#include <shobjidl.h>
#include "base/win/scoped_comptr.h"
#include "base/win/scoped_hdc.h"
#include "third_party/skia/include/core/SkBitmap.h"
#include "ui/base/dragdrop/os_exchange_data.h"
#include "ui/base/dragdrop/os_exchange_data_provider_win.h"
#include "ui/gfx/canvas.h"
#include "ui/gfx/gdi_util.h"
#include "ui/gfx/geometry/size.h"
#include "ui/gfx/image/image_skia.h"
#include "ui/gfx/skbitmap_operations.h"
namespace drag_utils {
static void SetDragImageOnDataObject(HBITMAP hbitmap,
const gfx::Size& size_in_pixels,
const gfx::Vector2d& cursor_offset,
IDataObject* data_object) {
base::win::ScopedComPtr<IDragSourceHelper> helper;
HRESULT rv = CoCreateInstance(CLSID_DragDropHelper, 0, CLSCTX_INPROC_SERVER,
IID_IDragSourceHelper, helper.ReceiveVoid());
if (SUCCEEDED(rv)) {
sdi.sizeDragImage = size_in_pixels.ToSIZE();
sdi.crColorKey = 0xFFFFFFFF;
sdi.hbmpDragImage = hbitmap;
sdi.ptOffset = gfx::PointAtOffsetFromOrigin(cursor_offset).ToPOINT();
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 CreateHBITMAPFromSkBitmap(const SkBitmap& sk_bitmap) {
base::win::ScopedGetDC screen_dc(NULL);
gfx::CreateBitmapHeader(sk_bitmap.width(), sk_bitmap.height(), &header);
void* bits;
HBITMAP bitmap =
CreateDIBSection(screen_dc, reinterpret_cast<BITMAPINFO*>(&header),
DIB_RGB_COLORS, &bits, NULL, 0);
if (!bitmap || !bits)
return NULL;
DCHECK_EQ(sk_bitmap.rowBytes(), static_cast<size_t>(sk_bitmap.width() * 4));
SkAutoLockPixels lock(sk_bitmap);
bits, sk_bitmap.getPixels(), sk_bitmap.height() * sk_bitmap.rowBytes());
return bitmap;
void SetDragImageOnDataObject(const gfx::ImageSkia& image_skia,
const gfx::Vector2d& cursor_offset,
ui::OSExchangeData* data_object) {
DCHECK(data_object && !image_skia.size().IsEmpty());
// InitializeFromBitmap() doesn't expect an alpha channel and is confused
// by premultiplied colors, so unpremultiply the bitmap.
// SetDragImageOnDataObject(HBITMAP) takes ownership of the bitmap.
HBITMAP bitmap = CreateHBITMAPFromSkBitmap(
if (bitmap) {
// Attach 'bitmap' to the data_object.
gfx::Size(image_skia.bitmap()->width(), image_skia.bitmap()->height()),
// TODO: the above code is used in non-Ash, while below is used in Ash. If we
// could figure this context out then we wouldn't do unnecessary work. However
// as it stands getting this information in ui/base would be a layering
// violation.
data_object->provider().SetDragImage(image_skia, cursor_offset);
} // namespace drag_utils