gecko-dev/widget/nsBaseDragService.cpp

870 lines
27 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "nsBaseDragService.h"
#include "nsITransferable.h"
#include "nsIServiceManager.h"
#include "nsITransferable.h"
#include "nsSize.h"
#include "nsXPCOM.h"
#include "nsISupportsPrimitives.h"
#include "nsCOMPtr.h"
#include "nsIInterfaceRequestorUtils.h"
#include "nsIFrame.h"
#include "nsIDocument.h"
#include "nsIContent.h"
#include "nsIPresShell.h"
#include "nsViewManager.h"
#include "nsINode.h"
#include "nsPresContext.h"
#include "nsIImageLoadingContent.h"
#include "imgIContainer.h"
#include "imgIRequest.h"
#include "ImageRegion.h"
#include "nsQueryObject.h"
#include "nsRegion.h"
#include "nsXULPopupManager.h"
#include "nsMenuPopupFrame.h"
#include "SVGImageContext.h"
#ifdef MOZ_XUL
#include "nsTreeBodyFrame.h"
#endif
#include "mozilla/MouseEvents.h"
#include "mozilla/Preferences.h"
#include "mozilla/dom/BindingDeclarations.h"
#include "mozilla/dom/DataTransferItemList.h"
#include "mozilla/dom/DataTransfer.h"
#include "mozilla/dom/DragEvent.h"
#include "mozilla/dom/MouseEventBinding.h"
#include "mozilla/dom/Selection.h"
#include "mozilla/gfx/2D.h"
#include "mozilla/Unused.h"
#include "nsFrameLoader.h"
#include "TabParent.h"
#include "gfxContext.h"
#include "gfxPlatform.h"
#include <algorithm>
using namespace mozilla;
using namespace mozilla::dom;
using namespace mozilla::gfx;
using namespace mozilla::image;
#define DRAGIMAGES_PREF "nglayout.enable_drag_images"
nsBaseDragService::nsBaseDragService()
: mCanDrop(false), mOnlyChromeDrop(false), mDoingDrag(false),
mHasImage(false), mUserCancelled(false),
mDragEventDispatchedToChildProcess(false),
mDragAction(DRAGDROP_ACTION_NONE),
mDragActionFromChildProcess(DRAGDROP_ACTION_UNINITIALIZED), mTargetSize(0,0),
mContentPolicyType(nsIContentPolicy::TYPE_OTHER),
mSuppressLevel(0), mInputSource(MouseEvent_Binding::MOZ_SOURCE_MOUSE)
{
}
nsBaseDragService::~nsBaseDragService() = default;
NS_IMPL_ISUPPORTS(nsBaseDragService, nsIDragService, nsIDragSession)
//---------------------------------------------------------
NS_IMETHODIMP
nsBaseDragService::SetCanDrop(bool aCanDrop)
{
mCanDrop = aCanDrop;
return NS_OK;
}
//---------------------------------------------------------
NS_IMETHODIMP
nsBaseDragService::GetCanDrop(bool * aCanDrop)
{
*aCanDrop = mCanDrop;
return NS_OK;
}
//---------------------------------------------------------
NS_IMETHODIMP
nsBaseDragService::SetOnlyChromeDrop(bool aOnlyChrome)
{
mOnlyChromeDrop = aOnlyChrome;
return NS_OK;
}
//---------------------------------------------------------
NS_IMETHODIMP
nsBaseDragService::GetOnlyChromeDrop(bool* aOnlyChrome)
{
*aOnlyChrome = mOnlyChromeDrop;
return NS_OK;
}
//---------------------------------------------------------
NS_IMETHODIMP
nsBaseDragService::SetDragAction(uint32_t anAction)
{
mDragAction = anAction;
return NS_OK;
}
//---------------------------------------------------------
NS_IMETHODIMP
nsBaseDragService::GetDragAction(uint32_t * anAction)
{
*anAction = mDragAction;
return NS_OK;
}
//---------------------------------------------------------
NS_IMETHODIMP
nsBaseDragService::SetTargetSize(nsSize aDragTargetSize)
{
mTargetSize = aDragTargetSize;
return NS_OK;
}
//---------------------------------------------------------
NS_IMETHODIMP
nsBaseDragService::GetTargetSize(nsSize * aDragTargetSize)
{
*aDragTargetSize = mTargetSize;
return NS_OK;
}
//-------------------------------------------------------------------------
NS_IMETHODIMP
nsBaseDragService::GetNumDropItems(uint32_t * aNumItems)
{
*aNumItems = 0;
return NS_ERROR_FAILURE;
}
//
// GetSourceDocument
//
// Returns the DOM document where the drag was initiated. This will be
// nullptr if the drag began outside of our application.
//
NS_IMETHODIMP
nsBaseDragService::GetSourceDocument(nsIDocument** aSourceDocument)
{
*aSourceDocument = mSourceDocument.get();
NS_IF_ADDREF(*aSourceDocument);
return NS_OK;
}
//
// GetSourceNode
//
// Returns the DOM node where the drag was initiated. This will be
// nullptr if the drag began outside of our application.
//
NS_IMETHODIMP
nsBaseDragService::GetSourceNode(nsINode** aSourceNode)
{
*aSourceNode = do_AddRef(mSourceNode).take();
return NS_OK;
}
NS_IMETHODIMP
nsBaseDragService::GetTriggeringPrincipalURISpec(nsACString& aPrincipalURISpec)
{
aPrincipalURISpec = mTriggeringPrincipalURISpec;
return NS_OK;
}
NS_IMETHODIMP
nsBaseDragService::SetTriggeringPrincipalURISpec(const nsACString& aPrincipalURISpec)
{
mTriggeringPrincipalURISpec = aPrincipalURISpec;
return NS_OK;
}
//-------------------------------------------------------------------------
NS_IMETHODIMP
nsBaseDragService::GetData(nsITransferable * aTransferable,
uint32_t aItemIndex)
{
return NS_ERROR_FAILURE;
}
//-------------------------------------------------------------------------
NS_IMETHODIMP
nsBaseDragService::IsDataFlavorSupported(const char *aDataFlavor,
bool *_retval)
{
return NS_ERROR_FAILURE;
}
NS_IMETHODIMP
nsBaseDragService::GetDataTransferXPCOM(DataTransfer** aDataTransfer)
{
*aDataTransfer = mDataTransfer;
NS_IF_ADDREF(*aDataTransfer);
return NS_OK;
}
NS_IMETHODIMP
nsBaseDragService::SetDataTransferXPCOM(DataTransfer* aDataTransfer)
{
NS_ENSURE_STATE(aDataTransfer);
mDataTransfer = aDataTransfer;
return NS_OK;
}
DataTransfer*
nsBaseDragService::GetDataTransfer()
{
return mDataTransfer;
}
void
nsBaseDragService::SetDataTransfer(DataTransfer* aDataTransfer)
{
mDataTransfer = aDataTransfer;
}
//-------------------------------------------------------------------------
NS_IMETHODIMP
nsBaseDragService::InvokeDragSession(nsINode *aDOMNode,
const nsACString& aPrincipalURISpec,
nsIArray* aTransferableArray,
uint32_t aActionType,
nsContentPolicyType aContentPolicyType =
nsIContentPolicy::TYPE_OTHER)
{
AUTO_PROFILER_LABEL("nsBaseDragService::InvokeDragSession", OTHER);
NS_ENSURE_TRUE(aDOMNode, NS_ERROR_INVALID_ARG);
NS_ENSURE_TRUE(mSuppressLevel == 0, NS_ERROR_FAILURE);
// stash the document of the dom node
mSourceDocument = aDOMNode->OwnerDoc();
mTriggeringPrincipalURISpec.Assign(aPrincipalURISpec);
mSourceNode = aDOMNode;
mContentPolicyType = aContentPolicyType;
mEndDragPoint = LayoutDeviceIntPoint(0, 0);
// When the mouse goes down, the selection code starts a mouse
// capture. However, this gets in the way of determining drag
// feedback for things like trees because the event coordinates
// are in the wrong coord system, so turn off mouse capture.
nsIPresShell::ClearMouseCapture(nullptr);
nsresult rv = InvokeDragSessionImpl(aTransferableArray,
mRegion, aActionType);
if (NS_FAILED(rv)) {
// Set mDoingDrag so that EndDragSession cleans up and sends the dragend event
// after the aborted drag.
mDoingDrag = true;
EndDragSession(true, 0);
}
return rv;
}
NS_IMETHODIMP
nsBaseDragService::InvokeDragSessionWithImage(nsINode* aDOMNode,
const nsACString& aPrincipalURISpec,
nsIArray* aTransferableArray,
uint32_t aActionType,
nsINode* aImage,
int32_t aImageX, int32_t aImageY,
DragEvent* aDragEvent,
DataTransfer* aDataTransfer)
{
NS_ENSURE_TRUE(aDragEvent, NS_ERROR_NULL_POINTER);
NS_ENSURE_TRUE(aDataTransfer, NS_ERROR_NULL_POINTER);
NS_ENSURE_TRUE(mSuppressLevel == 0, NS_ERROR_FAILURE);
mDataTransfer = aDataTransfer;
mSelection = nullptr;
mHasImage = true;
mDragPopup = nullptr;
mImage = aImage;
mImageOffset = CSSIntPoint(aImageX, aImageY);
mScreenPosition.x = aDragEvent->ScreenX(CallerType::System);
mScreenPosition.y = aDragEvent->ScreenY(CallerType::System);
mInputSource = aDragEvent->MozInputSource();
// If dragging within a XUL tree and no custom drag image was
// set, the region argument to InvokeDragSessionWithImage needs
// to be set to the area encompassing the selected rows of the
// tree to ensure that the drag feedback gets clipped to those
// rows. For other content, region should be null.
mRegion = Nothing();
#ifdef MOZ_XUL
if (aDOMNode && aDOMNode->IsContent() && !aImage) {
if (aDOMNode->NodeInfo()->Equals(nsGkAtoms::treechildren,
kNameSpaceID_XUL)) {
nsTreeBodyFrame* treeBody =
do_QueryFrame(aDOMNode->AsContent()->GetPrimaryFrame());
if (treeBody) {
mRegion = treeBody->GetSelectionRegion();
}
}
}
#endif
nsresult rv = InvokeDragSession(aDOMNode, aPrincipalURISpec,
aTransferableArray,
aActionType,
nsIContentPolicy::TYPE_INTERNAL_IMAGE);
mRegion = Nothing();
return rv;
}
NS_IMETHODIMP
nsBaseDragService::InvokeDragSessionWithSelection(Selection* aSelection,
const nsACString& aPrincipalURISpec,
nsIArray* aTransferableArray,
uint32_t aActionType,
DragEvent* aDragEvent,
DataTransfer* aDataTransfer)
{
NS_ENSURE_TRUE(aSelection, NS_ERROR_NULL_POINTER);
NS_ENSURE_TRUE(aDragEvent, NS_ERROR_NULL_POINTER);
NS_ENSURE_TRUE(mSuppressLevel == 0, NS_ERROR_FAILURE);
mDataTransfer = aDataTransfer;
mSelection = aSelection;
mHasImage = true;
mDragPopup = nullptr;
mImage = nullptr;
mImageOffset = CSSIntPoint();
mRegion = Nothing();
mScreenPosition.x = aDragEvent->ScreenX(CallerType::System);
mScreenPosition.y = aDragEvent->ScreenY(CallerType::System);
mInputSource = aDragEvent->MozInputSource();
// just get the focused node from the selection
// XXXndeakin this should actually be the deepest node that contains both
// endpoints of the selection
nsCOMPtr<nsINode> node = aSelection->GetFocusNode();
return InvokeDragSession(node, aPrincipalURISpec,
aTransferableArray,
aActionType,
nsIContentPolicy::TYPE_OTHER);
}
//-------------------------------------------------------------------------
NS_IMETHODIMP
nsBaseDragService::GetCurrentSession(nsIDragSession ** aSession)
{
if (!aSession)
return NS_ERROR_INVALID_ARG;
// "this" also implements a drag session, so say we are one but only
// if there is currently a drag going on.
if (!mSuppressLevel && mDoingDrag) {
*aSession = this;
NS_ADDREF(*aSession); // addRef because we're a "getter"
}
else
*aSession = nullptr;
return NS_OK;
}
//-------------------------------------------------------------------------
NS_IMETHODIMP
nsBaseDragService::StartDragSession()
{
if (mDoingDrag) {
return NS_ERROR_FAILURE;
}
mDoingDrag = true;
// By default dispatch drop also to content.
mOnlyChromeDrop = false;
return NS_OK;
}
void
nsBaseDragService::OpenDragPopup()
{
if (mDragPopup) {
nsXULPopupManager* pm = nsXULPopupManager::GetInstance();
if (pm) {
pm->ShowPopupAtScreen(mDragPopup, mScreenPosition.x - mImageOffset.x,
mScreenPosition.y - mImageOffset.y, false, nullptr);
}
}
}
int32_t
nsBaseDragService::TakeChildProcessDragAction()
{
// If the last event was dispatched to the child process, use the drag action
// assigned from it instead and return it. DRAGDROP_ACTION_UNINITIALIZED is
// returned otherwise.
int32_t retval = DRAGDROP_ACTION_UNINITIALIZED;
if (TakeDragEventDispatchedToChildProcess() &&
mDragActionFromChildProcess != DRAGDROP_ACTION_UNINITIALIZED) {
retval = mDragActionFromChildProcess;
}
return retval;
}
//-------------------------------------------------------------------------
NS_IMETHODIMP
nsBaseDragService::EndDragSession(bool aDoneDrag, uint32_t aKeyModifiers)
{
if (!mDoingDrag) {
return NS_ERROR_FAILURE;
}
if (aDoneDrag && !mSuppressLevel) {
FireDragEventAtSource(eDragEnd, aKeyModifiers);
}
if (mDragPopup) {
nsXULPopupManager* pm = nsXULPopupManager::GetInstance();
if (pm) {
pm->HidePopup(mDragPopup, false, true, false, false);
}
}
for (uint32_t i = 0; i < mChildProcesses.Length(); ++i) {
mozilla::Unused << mChildProcesses[i]->SendEndDragSession(aDoneDrag,
mUserCancelled,
mEndDragPoint,
aKeyModifiers);
// Continue sending input events with input priority when stopping the dnd
// session.
mChildProcesses[i]->SetInputPriorityEventEnabled(true);
}
mChildProcesses.Clear();
// mDataTransfer and the items it owns are going to die anyway, but we
// explicitly deref the contained data here so that we don't have to wait for
// CC to reclaim the memory.
if (XRE_IsParentProcess()) {
DiscardInternalTransferData();
}
mDoingDrag = false;
mCanDrop = false;
// release the source we've been holding on to.
mSourceDocument = nullptr;
mSourceNode = nullptr;
mTriggeringPrincipalURISpec.Truncate(0);
mSelection = nullptr;
mDataTransfer = nullptr;
mHasImage = false;
mUserCancelled = false;
mDragPopup = nullptr;
mImage = nullptr;
mImageOffset = CSSIntPoint();
mScreenPosition = CSSIntPoint();
mEndDragPoint = LayoutDeviceIntPoint(0, 0);
mInputSource = MouseEvent_Binding::MOZ_SOURCE_MOUSE;
mRegion = Nothing();
return NS_OK;
}
void
nsBaseDragService::DiscardInternalTransferData()
{
if (mDataTransfer && mSourceNode) {
MOZ_ASSERT(mDataTransfer);
DataTransferItemList* items = mDataTransfer->Items();
for (size_t i = 0; i < items->Length(); i++) {
bool found;
DataTransferItem* item = items->IndexedGetter(i, found);
// Non-OTHER items may still be needed by JS. Skip them.
if (!found || item->Kind() != DataTransferItem::KIND_OTHER) {
continue;
}
nsCOMPtr<nsIVariant> variant = item->DataNoSecurityCheck();
nsCOMPtr<nsIWritableVariant> writable = do_QueryInterface(variant);
if (writable) {
writable->SetAsEmpty();
}
}
}
}
NS_IMETHODIMP
nsBaseDragService::FireDragEventAtSource(EventMessage aEventMessage,
uint32_t aKeyModifiers)
{
if (mSourceNode && mSourceDocument && !mSuppressLevel) {
nsCOMPtr<nsIPresShell> presShell = mSourceDocument->GetShell();
if (presShell) {
nsEventStatus status = nsEventStatus_eIgnore;
WidgetDragEvent event(true, aEventMessage, nullptr);
event.inputSource = mInputSource;
if (aEventMessage == eDragEnd) {
event.mRefPoint = mEndDragPoint;
event.mUserCancelled = mUserCancelled;
}
event.mModifiers = aKeyModifiers;
// Send the drag event to APZ, which needs to know about them to be
// able to accurately detect the end of a drag gesture.
if (nsPresContext* presContext = presShell->GetPresContext()) {
if (nsCOMPtr<nsIWidget> widget = presContext->GetRootWidget()) {
widget->DispatchEventToAPZOnly(&event);
}
}
nsCOMPtr<nsIContent> content = do_QueryInterface(mSourceNode);
return presShell->HandleDOMEventWithTarget(content, &event, &status);
}
}
return NS_OK;
}
/* This is used by Windows and Mac to update the position of a popup being
* used as a drag image during the drag. This isn't used on GTK as it manages
* the drag popup itself.
*/
NS_IMETHODIMP
nsBaseDragService::DragMoved(int32_t aX, int32_t aY)
{
if (mDragPopup) {
nsIFrame* frame = mDragPopup->GetPrimaryFrame();
if (frame && frame->IsMenuPopupFrame()) {
CSSIntPoint cssPos = RoundedToInt(LayoutDeviceIntPoint(aX, aY) /
frame->PresContext()->CSSToDevPixelScale()) - mImageOffset;
(static_cast<nsMenuPopupFrame *>(frame))->MoveTo(cssPos, true);
}
}
return NS_OK;
}
static nsIPresShell*
GetPresShellForContent(nsINode* aDOMNode)
{
nsCOMPtr<nsIContent> content = do_QueryInterface(aDOMNode);
if (!content)
return nullptr;
nsCOMPtr<nsIDocument> document = content->GetComposedDoc();
if (document) {
document->FlushPendingNotifications(FlushType::Display);
return document->GetShell();
}
return nullptr;
}
nsresult
nsBaseDragService::DrawDrag(nsINode* aDOMNode,
const Maybe<CSSIntRegion>& aRegion,
CSSIntPoint aScreenPosition,
LayoutDeviceIntRect* aScreenDragRect,
RefPtr<SourceSurface>* aSurface,
nsPresContext** aPresContext)
{
*aSurface = nullptr;
*aPresContext = nullptr;
// use a default size, in case of an error.
aScreenDragRect->SetRect(aScreenPosition.x - mImageOffset.x,
aScreenPosition.y - mImageOffset.y,
1, 1);
// if a drag image was specified, use that, otherwise, use the source node
nsCOMPtr<nsINode> dragNode = mImage ? mImage.get() : aDOMNode;
// get the presshell for the node being dragged. If the drag image is not in
// a document or has no frame, get the presshell from the source drag node
nsIPresShell* presShell = GetPresShellForContent(dragNode);
if (!presShell && mImage)
presShell = GetPresShellForContent(aDOMNode);
if (!presShell)
return NS_ERROR_FAILURE;
*aPresContext = presShell->GetPresContext();
nsCOMPtr<nsIFrameLoaderOwner> flo = do_QueryInterface(dragNode);
if (flo) {
RefPtr<nsFrameLoader> fl = flo->GetFrameLoader();
if (fl) {
auto* tp = static_cast<mozilla::dom::TabParent*>(fl->GetRemoteBrowser());
if (tp && tp->TakeDragVisualization(*aSurface, aScreenDragRect)) {
if (mImage) {
// Just clear the surface if chrome has overridden it with an image.
*aSurface = nullptr;
}
return NS_OK;
}
}
}
// convert mouse position to dev pixels of the prescontext
CSSIntPoint screenPosition(aScreenPosition);
screenPosition.x -= mImageOffset.x;
screenPosition.y -= mImageOffset.y;
LayoutDeviceIntPoint screenPoint = ConvertToUnscaledDevPixels(*aPresContext, screenPosition);
aScreenDragRect->MoveTo(screenPoint.x, screenPoint.y);
// check if drag images are disabled
bool enableDragImages = Preferences::GetBool(DRAGIMAGES_PREF, true);
// didn't want an image, so just set the screen rectangle to the frame size
if (!enableDragImages || !mHasImage) {
// if a region was specified, set the screen rectangle to the area that
// the region occupies
CSSIntRect dragRect;
if (aRegion) {
// the region's coordinates are relative to the root frame
dragRect = aRegion->GetBounds();
nsIFrame* rootFrame = presShell->GetRootFrame();
CSSIntRect screenRect = rootFrame->GetScreenRect();
dragRect.MoveBy(screenRect.TopLeft());
}
else {
// otherwise, there was no region so just set the rectangle to
// the size of the primary frame of the content.
nsCOMPtr<nsIContent> content = do_QueryInterface(dragNode);
nsIFrame* frame = content->GetPrimaryFrame();
if (frame) {
dragRect = frame->GetScreenRect();
}
}
nsIntRect dragRectDev =
ToAppUnits(dragRect, nsPresContext::AppUnitsPerCSSPixel()).
ToOutsidePixels((*aPresContext)->AppUnitsPerDevPixel());
aScreenDragRect->SizeTo(dragRectDev.Width(), dragRectDev.Height());
return NS_OK;
}
// draw the image for selections
if (mSelection) {
LayoutDeviceIntPoint pnt(aScreenDragRect->TopLeft());
*aSurface = presShell->RenderSelection(mSelection, pnt, aScreenDragRect,
mImage ? 0 : nsIPresShell::RENDER_AUTO_SCALE);
return NS_OK;
}
// if a custom image was specified, check if it is an image node and draw
// using the source rather than the displayed image. But if mImage isn't
// an image or canvas, fall through to RenderNode below.
if (mImage) {
nsCOMPtr<nsIContent> content = do_QueryInterface(dragNode);
HTMLCanvasElement *canvas = HTMLCanvasElement::FromNodeOrNull(content);
if (canvas) {
return DrawDragForImage(*aPresContext, nullptr, canvas, aScreenDragRect, aSurface);
}
nsCOMPtr<nsIImageLoadingContent> imageLoader = do_QueryInterface(dragNode);
// for image nodes, create the drag image from the actual image data
if (imageLoader) {
return DrawDragForImage(*aPresContext, imageLoader, nullptr, aScreenDragRect, aSurface);
}
// If the image is a popup, use that as the image. This allows custom drag
// images that can change during the drag, but means that any platform
// default image handling won't occur.
// XXXndeakin this should be chrome-only
nsIFrame* frame = content->GetPrimaryFrame();
if (frame && frame->IsMenuPopupFrame()) {
mDragPopup = content;
}
}
if (!mDragPopup) {
// otherwise, just draw the node
uint32_t renderFlags = mImage ? 0 : nsIPresShell::RENDER_AUTO_SCALE;
if (renderFlags) {
nsCOMPtr<nsINode> dragINode = do_QueryInterface(dragNode);
// check if the dragged node itself is an img element
if (dragINode->NodeName().LowerCaseEqualsLiteral("img")) {
renderFlags = renderFlags | nsIPresShell::RENDER_IS_IMAGE;
} else {
nsINodeList* childList = dragINode->ChildNodes();
uint32_t length = childList->Length();
// check every childnode for being an img element
// XXXbz why don't we need to check descendants recursively?
for (uint32_t count = 0; count < length; ++count) {
if (childList->Item(count)->NodeName().LowerCaseEqualsLiteral("img")) {
// if the dragnode contains an image, set RENDER_IS_IMAGE flag
renderFlags = renderFlags | nsIPresShell::RENDER_IS_IMAGE;
break;
}
}
}
}
LayoutDeviceIntPoint pnt(aScreenDragRect->TopLeft());
*aSurface = presShell->RenderNode(dragNode, aRegion,
pnt, aScreenDragRect,
renderFlags);
}
// If an image was specified, reset the position from the offset that was supplied.
if (mImage) {
aScreenDragRect->MoveTo(screenPoint.x, screenPoint.y);
}
return NS_OK;
}
nsresult
nsBaseDragService::DrawDragForImage(nsPresContext* aPresContext,
nsIImageLoadingContent* aImageLoader,
HTMLCanvasElement* aCanvas,
LayoutDeviceIntRect* aScreenDragRect,
RefPtr<SourceSurface>* aSurface)
{
nsCOMPtr<imgIContainer> imgContainer;
if (aImageLoader) {
nsCOMPtr<imgIRequest> imgRequest;
nsresult rv = aImageLoader->GetRequest(nsIImageLoadingContent::CURRENT_REQUEST,
getter_AddRefs(imgRequest));
NS_ENSURE_SUCCESS(rv, rv);
if (!imgRequest)
return NS_ERROR_NOT_AVAILABLE;
rv = imgRequest->GetImage(getter_AddRefs(imgContainer));
NS_ENSURE_SUCCESS(rv, rv);
if (!imgContainer)
return NS_ERROR_NOT_AVAILABLE;
// use the size of the image as the size of the drag image
int32_t imageWidth, imageHeight;
rv = imgContainer->GetWidth(&imageWidth);
NS_ENSURE_SUCCESS(rv, rv);
rv = imgContainer->GetHeight(&imageHeight);
NS_ENSURE_SUCCESS(rv, rv);
aScreenDragRect->SizeTo(aPresContext->CSSPixelsToDevPixels(imageWidth),
aPresContext->CSSPixelsToDevPixels(imageHeight));
}
else {
// XXX The canvas size should be converted to dev pixels.
NS_ASSERTION(aCanvas, "both image and canvas are null");
nsIntSize sz = aCanvas->GetSize();
aScreenDragRect->SizeTo(sz.width, sz.height);
}
nsIntSize destSize;
destSize.width = aScreenDragRect->Width();
destSize.height = aScreenDragRect->Height();
if (destSize.width == 0 || destSize.height == 0)
return NS_ERROR_FAILURE;
nsresult result = NS_OK;
if (aImageLoader) {
RefPtr<DrawTarget> dt =
gfxPlatform::GetPlatform()->
CreateOffscreenContentDrawTarget(destSize,
SurfaceFormat::B8G8R8A8);
if (!dt || !dt->IsValid())
return NS_ERROR_FAILURE;
RefPtr<gfxContext> ctx = gfxContext::CreateOrNull(dt);
if (!ctx)
return NS_ERROR_FAILURE;
ImgDrawResult res =
imgContainer->Draw(ctx, destSize, ImageRegion::Create(destSize),
imgIContainer::FRAME_CURRENT,
SamplingFilter::GOOD, /* no SVGImageContext */ Nothing(),
imgIContainer::FLAG_SYNC_DECODE, 1.0);
if (res == ImgDrawResult::BAD_IMAGE || res == ImgDrawResult::BAD_ARGS) {
return NS_ERROR_FAILURE;
}
*aSurface = dt->Snapshot();
} else {
*aSurface = aCanvas->GetSurfaceSnapshot();
}
return result;
}
LayoutDeviceIntPoint
nsBaseDragService::ConvertToUnscaledDevPixels(nsPresContext* aPresContext,
CSSIntPoint aScreenPosition)
{
int32_t adj = aPresContext->DeviceContext()->AppUnitsPerDevPixelAtUnitFullZoom();
return LayoutDeviceIntPoint(nsPresContext::CSSPixelsToAppUnits(aScreenPosition.x) / adj,
nsPresContext::CSSPixelsToAppUnits(aScreenPosition.y) / adj);
}
NS_IMETHODIMP
nsBaseDragService::Suppress()
{
EndDragSession(false, 0);
++mSuppressLevel;
return NS_OK;
}
NS_IMETHODIMP
nsBaseDragService::Unsuppress()
{
--mSuppressLevel;
return NS_OK;
}
NS_IMETHODIMP
nsBaseDragService::UserCancelled()
{
mUserCancelled = true;
return NS_OK;
}
NS_IMETHODIMP
nsBaseDragService::UpdateDragEffect()
{
mDragActionFromChildProcess = mDragAction;
return NS_OK;
}
NS_IMETHODIMP
nsBaseDragService::UpdateDragImage(nsINode* aImage, int32_t aImageX, int32_t aImageY)
{
// Don't change the image if this is a drag from another source or if there
// is a drag popup.
if (!mSourceNode || mDragPopup)
return NS_OK;
mImage = aImage;
mImageOffset = CSSIntPoint(aImageX, aImageY);
return NS_OK;
}
NS_IMETHODIMP
nsBaseDragService::DragEventDispatchedToChildProcess()
{
mDragEventDispatchedToChildProcess = true;
return NS_OK;
}
bool
nsBaseDragService::MaybeAddChildProcess(mozilla::dom::ContentParent* aChild)
{
if (!mChildProcesses.Contains(aChild)) {
mChildProcesses.AppendElement(aChild);
return true;
}
return false;
}