1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/widget/windows/nsNativeDragTarget.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,462 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +#include <stdio.h>
1.10 +#include "nsIDragService.h"
1.11 +#include "nsWidgetsCID.h"
1.12 +#include "nsNativeDragTarget.h"
1.13 +#include "nsDragService.h"
1.14 +#include "nsIServiceManager.h"
1.15 +#include "nsIDOMNode.h"
1.16 +#include "nsCOMPtr.h"
1.17 +
1.18 +#include "nsIWidget.h"
1.19 +#include "nsWindow.h"
1.20 +#include "nsClipboard.h"
1.21 +#include "KeyboardLayout.h"
1.22 +
1.23 +#include "mozilla/MouseEvents.h"
1.24 +
1.25 +using namespace mozilla;
1.26 +using namespace mozilla::widget;
1.27 +
1.28 +/* Define Interface IDs */
1.29 +static NS_DEFINE_IID(kIDragServiceIID, NS_IDRAGSERVICE_IID);
1.30 +
1.31 +// This is cached for Leave notification
1.32 +static POINTL gDragLastPoint;
1.33 +
1.34 +/*
1.35 + * class nsNativeDragTarget
1.36 + */
1.37 +nsNativeDragTarget::nsNativeDragTarget(nsIWidget * aWidget)
1.38 + : m_cRef(0),
1.39 + mEffectsAllowed(DROPEFFECT_MOVE | DROPEFFECT_COPY | DROPEFFECT_LINK),
1.40 + mEffectsPreferred(DROPEFFECT_NONE),
1.41 + mTookOwnRef(false), mWidget(aWidget), mDropTargetHelper(nullptr)
1.42 +{
1.43 + static NS_DEFINE_IID(kCDragServiceCID, NS_DRAGSERVICE_CID);
1.44 +
1.45 + mHWnd = (HWND)mWidget->GetNativeData(NS_NATIVE_WINDOW);
1.46 +
1.47 + /*
1.48 + * Create/Get the DragService that we have implemented
1.49 + */
1.50 + CallGetService(kCDragServiceCID, &mDragService);
1.51 +}
1.52 +
1.53 +nsNativeDragTarget::~nsNativeDragTarget()
1.54 +{
1.55 + NS_RELEASE(mDragService);
1.56 +
1.57 + if (mDropTargetHelper) {
1.58 + mDropTargetHelper->Release();
1.59 + mDropTargetHelper = nullptr;
1.60 + }
1.61 +}
1.62 +
1.63 +// IUnknown methods - see iunknown.h for documentation
1.64 +STDMETHODIMP
1.65 +nsNativeDragTarget::QueryInterface(REFIID riid, void** ppv)
1.66 +{
1.67 + *ppv=nullptr;
1.68 +
1.69 + if (IID_IUnknown == riid || IID_IDropTarget == riid)
1.70 + *ppv=this;
1.71 +
1.72 + if (nullptr!=*ppv) {
1.73 + ((LPUNKNOWN)*ppv)->AddRef();
1.74 + return S_OK;
1.75 + }
1.76 +
1.77 + return E_NOINTERFACE;
1.78 +}
1.79 +
1.80 +STDMETHODIMP_(ULONG)
1.81 +nsNativeDragTarget::AddRef(void)
1.82 +{
1.83 + ++m_cRef;
1.84 + NS_LOG_ADDREF(this, m_cRef, "nsNativeDragTarget", sizeof(*this));
1.85 + return m_cRef;
1.86 +}
1.87 +
1.88 +STDMETHODIMP_(ULONG) nsNativeDragTarget::Release(void)
1.89 +{
1.90 + --m_cRef;
1.91 + NS_LOG_RELEASE(this, m_cRef, "nsNativeDragTarget");
1.92 + if (0 != m_cRef)
1.93 + return m_cRef;
1.94 +
1.95 + delete this;
1.96 + return 0;
1.97 +}
1.98 +
1.99 +void
1.100 +nsNativeDragTarget::GetGeckoDragAction(DWORD grfKeyState, LPDWORD pdwEffect,
1.101 + uint32_t * aGeckoAction)
1.102 +{
1.103 + // If a window is disabled or a modal window is on top of it
1.104 + // (which implies it is disabled), then we should not allow dropping.
1.105 + if (!mWidget->IsEnabled()) {
1.106 + *pdwEffect = DROPEFFECT_NONE;
1.107 + *aGeckoAction = nsIDragService::DRAGDROP_ACTION_NONE;
1.108 + return;
1.109 + }
1.110 +
1.111 + // If the user explicitly uses a modifier key, they want the associated action
1.112 + // Shift + Control -> LINK, Shift -> MOVE, Ctrl -> COPY
1.113 + DWORD desiredEffect = DROPEFFECT_NONE;
1.114 + if ((grfKeyState & MK_CONTROL) && (grfKeyState & MK_SHIFT)) {
1.115 + desiredEffect = DROPEFFECT_LINK;
1.116 + } else if (grfKeyState & MK_SHIFT) {
1.117 + desiredEffect = DROPEFFECT_MOVE;
1.118 + } else if (grfKeyState & MK_CONTROL) {
1.119 + desiredEffect = DROPEFFECT_COPY;
1.120 + }
1.121 +
1.122 + // Determine the desired effect from what is allowed and preferred.
1.123 + if (!(desiredEffect &= mEffectsAllowed)) {
1.124 + // No modifier key effect is set which is also allowed, check
1.125 + // the preference of the data.
1.126 + desiredEffect = mEffectsPreferred & mEffectsAllowed;
1.127 + if (!desiredEffect) {
1.128 + // No preference is set, so just fall back to the allowed effect itself
1.129 + desiredEffect = mEffectsAllowed;
1.130 + }
1.131 + }
1.132 +
1.133 + // Otherwise we should specify the first available effect
1.134 + // from MOVE, COPY, or LINK.
1.135 + if (desiredEffect & DROPEFFECT_MOVE) {
1.136 + *pdwEffect = DROPEFFECT_MOVE;
1.137 + *aGeckoAction = nsIDragService::DRAGDROP_ACTION_MOVE;
1.138 + } else if (desiredEffect & DROPEFFECT_COPY) {
1.139 + *pdwEffect = DROPEFFECT_COPY;
1.140 + *aGeckoAction = nsIDragService::DRAGDROP_ACTION_COPY;
1.141 + } else if (desiredEffect & DROPEFFECT_LINK) {
1.142 + *pdwEffect = DROPEFFECT_LINK;
1.143 + *aGeckoAction = nsIDragService::DRAGDROP_ACTION_LINK;
1.144 + } else {
1.145 + *pdwEffect = DROPEFFECT_NONE;
1.146 + *aGeckoAction = nsIDragService::DRAGDROP_ACTION_NONE;
1.147 + }
1.148 +}
1.149 +
1.150 +inline
1.151 +bool
1.152 +IsKeyDown(char key)
1.153 +{
1.154 + return GetKeyState(key) < 0;
1.155 +}
1.156 +
1.157 +void
1.158 +nsNativeDragTarget::DispatchDragDropEvent(uint32_t aEventType, POINTL aPT)
1.159 +{
1.160 + nsEventStatus status;
1.161 + WidgetDragEvent event(true, aEventType, mWidget);
1.162 +
1.163 + nsWindow * win = static_cast<nsWindow *>(mWidget);
1.164 + win->InitEvent(event);
1.165 + POINT cpos;
1.166 +
1.167 + cpos.x = aPT.x;
1.168 + cpos.y = aPT.y;
1.169 +
1.170 + if (mHWnd != nullptr) {
1.171 + ::ScreenToClient(mHWnd, &cpos);
1.172 + event.refPoint.x = cpos.x;
1.173 + event.refPoint.y = cpos.y;
1.174 + } else {
1.175 + event.refPoint.x = 0;
1.176 + event.refPoint.y = 0;
1.177 + }
1.178 +
1.179 + ModifierKeyState modifierKeyState;
1.180 + modifierKeyState.InitInputEvent(event);
1.181 +
1.182 + event.inputSource = static_cast<nsBaseDragService*>(mDragService)->GetInputSource();
1.183 +
1.184 + mWidget->DispatchEvent(&event, status);
1.185 +}
1.186 +
1.187 +void
1.188 +nsNativeDragTarget::ProcessDrag(uint32_t aEventType,
1.189 + DWORD grfKeyState,
1.190 + POINTL ptl,
1.191 + DWORD* pdwEffect)
1.192 +{
1.193 + // Before dispatching the event make sure we have the correct drop action set
1.194 + uint32_t geckoAction;
1.195 + GetGeckoDragAction(grfKeyState, pdwEffect, &geckoAction);
1.196 +
1.197 + // Set the current action into the Gecko specific type
1.198 + nsCOMPtr<nsIDragSession> currSession;
1.199 + mDragService->GetCurrentSession(getter_AddRefs(currSession));
1.200 + if (!currSession) {
1.201 + return;
1.202 + }
1.203 +
1.204 + currSession->SetDragAction(geckoAction);
1.205 +
1.206 + // Dispatch the event into Gecko
1.207 + DispatchDragDropEvent(aEventType, ptl);
1.208 +
1.209 + if (aEventType != NS_DRAGDROP_DROP) {
1.210 + // Get the cached drag effect from the drag service, the data member should
1.211 + // have been set by whoever handled the WidgetGUIEvent or nsIDOMEvent on
1.212 + // drags.
1.213 + bool canDrop;
1.214 + currSession->GetCanDrop(&canDrop);
1.215 + if (!canDrop) {
1.216 + *pdwEffect = DROPEFFECT_NONE;
1.217 + }
1.218 + }
1.219 +
1.220 + // Clear the cached value
1.221 + currSession->SetCanDrop(false);
1.222 +}
1.223 +
1.224 +// IDropTarget methods
1.225 +STDMETHODIMP
1.226 +nsNativeDragTarget::DragEnter(LPDATAOBJECT pIDataSource,
1.227 + DWORD grfKeyState,
1.228 + POINTL ptl,
1.229 + DWORD* pdwEffect)
1.230 +{
1.231 + if (!mDragService) {
1.232 + return E_FAIL;
1.233 + }
1.234 +
1.235 + mEffectsAllowed = *pdwEffect;
1.236 + AddLinkSupportIfCanBeGenerated(pIDataSource);
1.237 +
1.238 + // Drag and drop image helper
1.239 + if (GetDropTargetHelper()) {
1.240 + POINT pt = { ptl.x, ptl.y };
1.241 + GetDropTargetHelper()->DragEnter(mHWnd, pIDataSource, &pt, *pdwEffect);
1.242 + }
1.243 +
1.244 + // save a ref to this, in case the window is destroyed underneath us
1.245 + NS_ASSERTION(!mTookOwnRef, "own ref already taken!");
1.246 + this->AddRef();
1.247 + mTookOwnRef = true;
1.248 +
1.249 + // tell the drag service about this drag (it may have come from an
1.250 + // outside app).
1.251 + mDragService->StartDragSession();
1.252 +
1.253 + void* tempOutData = nullptr;
1.254 + uint32_t tempDataLen = 0;
1.255 + nsresult loadResult = nsClipboard::GetNativeDataOffClipboard(
1.256 + pIDataSource, 0, ::RegisterClipboardFormat(CFSTR_PREFERREDDROPEFFECT), nullptr, &tempOutData, &tempDataLen);
1.257 + if (NS_SUCCEEDED(loadResult) && tempOutData) {
1.258 + mEffectsPreferred = *((DWORD*)tempOutData);
1.259 + nsMemory::Free(tempOutData);
1.260 + } else {
1.261 + // We have no preference if we can't obtain it
1.262 + mEffectsPreferred = DROPEFFECT_NONE;
1.263 + }
1.264 +
1.265 + // Set the native data object into drag service
1.266 + //
1.267 + // This cast is ok because in the constructor we created a
1.268 + // the actual implementation we wanted, so we know this is
1.269 + // a nsDragService. It should be a private interface, though.
1.270 + nsDragService * winDragService =
1.271 + static_cast<nsDragService *>(mDragService);
1.272 + winDragService->SetIDataObject(pIDataSource);
1.273 +
1.274 + // Now process the native drag state and then dispatch the event
1.275 + ProcessDrag(NS_DRAGDROP_ENTER, grfKeyState, ptl, pdwEffect);
1.276 +
1.277 + return S_OK;
1.278 +}
1.279 +
1.280 +void
1.281 +nsNativeDragTarget::AddLinkSupportIfCanBeGenerated(LPDATAOBJECT aIDataSource)
1.282 +{
1.283 + // If we don't have a link effect, but we can generate one, fix the
1.284 + // drop effect to include it.
1.285 + if (!(mEffectsAllowed & DROPEFFECT_LINK) && aIDataSource) {
1.286 + if (S_OK == ::OleQueryLinkFromData(aIDataSource)) {
1.287 + mEffectsAllowed |= DROPEFFECT_LINK;
1.288 + }
1.289 + }
1.290 +}
1.291 +
1.292 +STDMETHODIMP
1.293 +nsNativeDragTarget::DragOver(DWORD grfKeyState,
1.294 + POINTL ptl,
1.295 + LPDWORD pdwEffect)
1.296 +{
1.297 + if (!mDragService) {
1.298 + return E_FAIL;
1.299 + }
1.300 +
1.301 + // If a LINK effect could be generated previously from a DragEnter(),
1.302 + // then we should include it as an allowed effect.
1.303 + mEffectsAllowed = (*pdwEffect) | (mEffectsAllowed & DROPEFFECT_LINK);
1.304 +
1.305 + nsCOMPtr<nsIDragSession> currentDragSession;
1.306 + mDragService->GetCurrentSession(getter_AddRefs(currentDragSession));
1.307 + if (!currentDragSession) {
1.308 + return S_OK; // Drag was canceled.
1.309 + }
1.310 +
1.311 + // without the AddRef() |this| can get destroyed in an event handler
1.312 + this->AddRef();
1.313 +
1.314 + // Drag and drop image helper
1.315 + if (GetDropTargetHelper()) {
1.316 + POINT pt = { ptl.x, ptl.y };
1.317 + GetDropTargetHelper()->DragOver(&pt, *pdwEffect);
1.318 + }
1.319 +
1.320 + mDragService->FireDragEventAtSource(NS_DRAGDROP_DRAG);
1.321 + // Now process the native drag state and then dispatch the event
1.322 + ProcessDrag(NS_DRAGDROP_OVER, grfKeyState, ptl, pdwEffect);
1.323 +
1.324 + this->Release();
1.325 +
1.326 + return S_OK;
1.327 +}
1.328 +
1.329 +STDMETHODIMP
1.330 +nsNativeDragTarget::DragLeave()
1.331 +{
1.332 + if (!mDragService) {
1.333 + return E_FAIL;
1.334 + }
1.335 +
1.336 + // Drag and drop image helper
1.337 + if (GetDropTargetHelper()) {
1.338 + GetDropTargetHelper()->DragLeave();
1.339 + }
1.340 +
1.341 + // dispatch the event into Gecko
1.342 + DispatchDragDropEvent(NS_DRAGDROP_EXIT, gDragLastPoint);
1.343 +
1.344 + nsCOMPtr<nsIDragSession> currentDragSession;
1.345 + mDragService->GetCurrentSession(getter_AddRefs(currentDragSession));
1.346 +
1.347 + if (currentDragSession) {
1.348 + nsCOMPtr<nsIDOMNode> sourceNode;
1.349 + currentDragSession->GetSourceNode(getter_AddRefs(sourceNode));
1.350 +
1.351 + if (!sourceNode) {
1.352 + // We're leaving a window while doing a drag that was
1.353 + // initiated in a different app. End the drag session, since
1.354 + // we're done with it for now (until the user drags back into
1.355 + // mozilla).
1.356 + mDragService->EndDragSession(false);
1.357 + }
1.358 + }
1.359 +
1.360 + // release the ref that was taken in DragEnter
1.361 + NS_ASSERTION(mTookOwnRef, "want to release own ref, but not taken!");
1.362 + if (mTookOwnRef) {
1.363 + this->Release();
1.364 + mTookOwnRef = false;
1.365 + }
1.366 +
1.367 + return S_OK;
1.368 +}
1.369 +
1.370 +void
1.371 +nsNativeDragTarget::DragCancel()
1.372 +{
1.373 + // Cancel the drag session if we did DragEnter.
1.374 + if (mTookOwnRef) {
1.375 + if (GetDropTargetHelper()) {
1.376 + GetDropTargetHelper()->DragLeave();
1.377 + }
1.378 + if (mDragService) {
1.379 + mDragService->EndDragSession(false);
1.380 + }
1.381 + this->Release(); // matching the AddRef in DragEnter
1.382 + mTookOwnRef = false;
1.383 + }
1.384 +}
1.385 +
1.386 +STDMETHODIMP
1.387 +nsNativeDragTarget::Drop(LPDATAOBJECT pData,
1.388 + DWORD grfKeyState,
1.389 + POINTL aPT,
1.390 + LPDWORD pdwEffect)
1.391 +{
1.392 + if (!mDragService) {
1.393 + return E_FAIL;
1.394 + }
1.395 +
1.396 + mEffectsAllowed = *pdwEffect;
1.397 + AddLinkSupportIfCanBeGenerated(pData);
1.398 +
1.399 + // Drag and drop image helper
1.400 + if (GetDropTargetHelper()) {
1.401 + POINT pt = { aPT.x, aPT.y };
1.402 + GetDropTargetHelper()->Drop(pData, &pt, *pdwEffect);
1.403 + }
1.404 +
1.405 + // Set the native data object into the drag service
1.406 + //
1.407 + // This cast is ok because in the constructor we created a
1.408 + // the actual implementation we wanted, so we know this is
1.409 + // a nsDragService (but it should still be a private interface)
1.410 + nsDragService* winDragService = static_cast<nsDragService*>(mDragService);
1.411 + winDragService->SetIDataObject(pData);
1.412 +
1.413 + // NOTE: ProcessDrag spins the event loop which may destroy arbitrary objects.
1.414 + // We use strong refs to prevent it from destroying these:
1.415 + nsRefPtr<nsNativeDragTarget> kungFuDeathGrip = this;
1.416 + nsCOMPtr<nsIDragService> serv = mDragService;
1.417 +
1.418 + // Now process the native drag state and then dispatch the event
1.419 + ProcessDrag(NS_DRAGDROP_DROP, grfKeyState, aPT, pdwEffect);
1.420 +
1.421 + nsCOMPtr<nsIDragSession> currentDragSession;
1.422 + serv->GetCurrentSession(getter_AddRefs(currentDragSession));
1.423 + if (!currentDragSession) {
1.424 + return S_OK; // DragCancel() was called.
1.425 + }
1.426 +
1.427 + // Let the win drag service know whether this session experienced
1.428 + // a drop event within the application. Drop will not oocur if the
1.429 + // drop landed outside the app. (used in tab tear off, bug 455884)
1.430 + winDragService->SetDroppedLocal();
1.431 +
1.432 + // tell the drag service we're done with the session
1.433 + // Use GetMessagePos to get the position of the mouse at the last message
1.434 + // seen by the event loop. (Bug 489729)
1.435 + DWORD pos = ::GetMessagePos();
1.436 + POINT cpos;
1.437 + cpos.x = GET_X_LPARAM(pos);
1.438 + cpos.y = GET_Y_LPARAM(pos);
1.439 + winDragService->SetDragEndPoint(nsIntPoint(cpos.x, cpos.y));
1.440 + serv->EndDragSession(true);
1.441 +
1.442 + // release the ref that was taken in DragEnter
1.443 + NS_ASSERTION(mTookOwnRef, "want to release own ref, but not taken!");
1.444 + if (mTookOwnRef) {
1.445 + this->Release();
1.446 + mTookOwnRef = false;
1.447 + }
1.448 +
1.449 + return S_OK;
1.450 +}
1.451 +
1.452 +/**
1.453 + * By lazy loading mDropTargetHelper we save 50-70ms of startup time
1.454 + * which is ~5% of startup time.
1.455 +*/
1.456 +IDropTargetHelper*
1.457 +nsNativeDragTarget::GetDropTargetHelper()
1.458 +{
1.459 + if (!mDropTargetHelper) {
1.460 + CoCreateInstance(CLSID_DragDropHelper, nullptr, CLSCTX_INPROC_SERVER,
1.461 + IID_IDropTargetHelper, (LPVOID*)&mDropTargetHelper);
1.462 + }
1.463 +
1.464 + return mDropTargetHelper;
1.465 +}
