gecko-dev/widget/nsBaseDragService.cpp
Olli Pettay bf03e4a42e Bug 1552814, make it possible to start dnd from dragable element even if DataTransfer is empty, r=NeilDeakin
Chrome and old Edge at least seem to have this behavior, and this way the testcase on the bug doesn't trigger click anymore since
we enter dnd mode and get dragleave etc. events.

Manually tested on linux and Windows, and annyg tested on Mac

Update test_dragstart.html's draggable=true test to follow the pattern used by other tests

Differential Revision: https://phabricator.services.mozilla.com/D48208

--HG--
extra : moz-landing-system : lando
2019-10-07 21:01:57 +00:00

888 lines
28 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 "nsArrayUtils.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 "nsFrameLoaderOwner.h"
#include "mozilla/dom/Document.h"
#include "nsIContent.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/PresShell.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 "BrowserParent.h"
#include "nsIMutableArray.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),
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::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(Document** 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::GetTriggeringPrincipal(nsIPrincipal** aPrincipal) {
NS_IF_ADDREF(*aPrincipal = mTriggeringPrincipal);
return NS_OK;
}
NS_IMETHODIMP
nsBaseDragService::SetTriggeringPrincipal(nsIPrincipal* aPrincipal) {
mTriggeringPrincipal = aPrincipal;
return NS_OK;
}
NS_IMETHODIMP
nsBaseDragService::GetCsp(nsIContentSecurityPolicy** aCsp) {
NS_IF_ADDREF(*aCsp = mCsp);
return NS_OK;
}
NS_IMETHODIMP
nsBaseDragService::SetCsp(nsIContentSecurityPolicy* aCsp) {
mCsp = aCsp;
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, nsIPrincipal* aPrincipal, nsIContentSecurityPolicy* aCsp,
nsIArray* aTransferableArray, uint32_t aActionType,
nsContentPolicyType aContentPolicyType = nsIContentPolicy::TYPE_OTHER) {
AUTO_PROFILER_LABEL("nsBaseDragService::InvokeDragSession", OTHER);
// If you're hitting this, a test is causing the browser to attempt to enter
// the drag-drop native nested event loop, which will put the browser in a
// state that won't run tests properly until there's manual intervention
// to exit the drag-drop loop (either by moving the mouse or hitting escape),
// which can't be done from script since we're in the nested loop.
//
// The best way to avoid this is to catch the dragstart event on the item
// being dragged, and then to call preventDefault() and stopPropagating() on
// it. Alternatively, use EventUtils.synthesizeDragStart, which will do this
// for you.
if (XRE_IsParentProcess()) {
MOZ_ASSERT(
!xpc::IsInAutomation(),
"About to start drag-drop native loop on which will prevent later "
"tests from running properly.");
}
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();
mTriggeringPrincipal = aPrincipal;
mCsp = aCsp;
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.
PresShell::ClearMouseCapture(nullptr);
uint32_t length = 0;
mozilla::Unused << aTransferableArray->GetLength(&length);
if (!length) {
nsCOMPtr<nsIMutableArray> mutableArray =
do_QueryInterface(aTransferableArray);
if (mutableArray) {
// In order to be able trigger dnd, we need to have some transferable
// object.
nsCOMPtr<nsITransferable> trans =
do_CreateInstance("@mozilla.org/widget/transferable;1");
trans->Init(nullptr);
trans->SetRequestingPrincipal(mSourceNode->NodePrincipal());
trans->SetContentPolicyType(mContentPolicyType);
mutableArray->AppendElement(trans);
}
} else {
for (uint32_t i = 0; i < length; ++i) {
nsCOMPtr<nsITransferable> trans =
do_QueryElementAt(aTransferableArray, i);
if (trans) {
// Set the requestingPrincipal on the transferable.
trans->SetRequestingPrincipal(mSourceNode->NodePrincipal());
trans->SetContentPolicyType(mContentPolicyType);
}
}
}
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, nsIPrincipal* aPrincipal, nsIContentSecurityPolicy* aCsp,
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);
mDragStartData = nullptr;
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, aPrincipal, aCsp, aTransferableArray,
aActionType, nsIContentPolicy::TYPE_INTERNAL_IMAGE);
mRegion = Nothing();
return rv;
}
NS_IMETHODIMP
nsBaseDragService::InvokeDragSessionWithRemoteImage(
nsINode* aDOMNode, nsIPrincipal* aPrincipal, nsIContentSecurityPolicy* aCsp,
nsIArray* aTransferableArray, uint32_t aActionType,
RemoteDragStartData* aDragStartData, 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 = nullptr;
mDragStartData = aDragStartData;
mImageOffset = CSSIntPoint(0, 0);
mScreenPosition.x = aDragEvent->ScreenX(CallerType::System);
mScreenPosition.y = aDragEvent->ScreenY(CallerType::System);
mInputSource = aDragEvent->MozInputSource();
nsresult rv =
InvokeDragSession(aDOMNode, aPrincipal, aCsp, aTransferableArray,
aActionType, nsIContentPolicy::TYPE_INTERNAL_IMAGE);
mRegion = Nothing();
return rv;
}
NS_IMETHODIMP
nsBaseDragService::InvokeDragSessionWithSelection(
Selection* aSelection, nsIPrincipal* aPrincipal,
nsIContentSecurityPolicy* aCsp, 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();
mDragStartData = nullptr;
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, aPrincipal, aCsp, 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;
mTriggeringPrincipal = nullptr;
mCsp = nullptr;
mSelection = nullptr;
mDataTransfer = nullptr;
mHasImage = false;
mUserCancelled = false;
mDragPopup = nullptr;
mDragStartData = 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) {
RefPtr<PresShell> presShell = mSourceDocument->GetPresShell();
if (presShell) {
nsEventStatus status = nsEventStatus_eIgnore;
WidgetDragEvent event(true, aEventMessage, nullptr);
event.mInputSource = 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 PresShell* GetPresShellForContent(nsINode* aDOMNode) {
nsCOMPtr<nsIContent> content = do_QueryInterface(aDOMNode);
if (!content) return nullptr;
RefPtr<Document> document = content->GetComposedDoc();
if (document) {
document->FlushPendingNotifications(FlushType::Display);
return document->GetPresShell();
}
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
PresShell* presShell = GetPresShellForContent(dragNode);
if (!presShell && mImage) {
presShell = GetPresShellForContent(aDOMNode);
}
if (!presShell) {
return NS_ERROR_FAILURE;
}
*aPresContext = presShell->GetPresContext();
if (mDragStartData) {
if (mImage) {
// Just clear the surface if chrome has overridden it with an image.
*aSurface = nullptr;
} else {
*aSurface = mDragStartData->TakeVisualization(aScreenDragRect);
}
mDragStartData = 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, 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 ? RenderImageFlags::None : RenderImageFlags::AutoScale);
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
RenderImageFlags renderFlags =
mImage ? RenderImageFlags::None : RenderImageFlags::AutoScale;
if (renderFlags != RenderImageFlags::None) {
// check if the dragged node itself is an img element
if (dragNode->NodeName().LowerCaseEqualsLiteral("img")) {
renderFlags = renderFlags | RenderImageFlags::IsImage;
} else {
nsINodeList* childList = dragNode->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 RenderImageFlags::IsImage
// flag
renderFlags = renderFlags | RenderImageFlags::IsImage;
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 ||
res == ImgDrawResult::NOT_SUPPORTED) {
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;
}
bool nsBaseDragService::RemoveAllChildProcesses() {
for (uint32_t c = 0; c < mChildProcesses.Length(); c++) {
mozilla::Unused << mChildProcesses[c]->SendEndDragSession(
true, false, LayoutDeviceIntPoint(), 0);
}
mChildProcesses.Clear();
return true;
}