Drag-and-drop: DragEnter, DragOver, DragLeave, DragDrop

third_party/WebKit/Source/web/WebViewImpl.cpp

 /*
  * Copyright (C) 2011, 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 223 matching lines @@
 // invocations.
 static Vector<std::unique_ptr<ScopedPageLoadDeferrer>>&
 pageLoadDeferrerStack() {
   DEFINE_STATIC_LOCAL(Vector<std::unique_ptr<ScopedPageLoadDeferrer>>,
                       deferrerStack, ());
   return deferrerStack;
 }
 
 // Ensure that the WebDragOperation enum values stay in sync with the original
 // DragOperation constants.
+// TODO(paulmeyer): Move this into WebFrameWidgetBase once all drag-and-drop
+// functions are out of WebViewImpl. See crbug.com/647249.
 #define STATIC_ASSERT_ENUM(a, b)                            \
   static_assert(static_cast<int>(a) == static_cast<int>(b), \
                 "mismatching enum : " #a)
 STATIC_ASSERT_ENUM(DragOperationNone, WebDragOperationNone);
 STATIC_ASSERT_ENUM(DragOperationCopy, WebDragOperationCopy);
 STATIC_ASSERT_ENUM(DragOperationLink, WebDragOperationLink);
 STATIC_ASSERT_ENUM(DragOperationGeneric, WebDragOperationGeneric);
 STATIC_ASSERT_ENUM(DragOperationPrivate, WebDragOperationPrivate);
 STATIC_ASSERT_ENUM(DragOperationMove, WebDragOperationMove);
 STATIC_ASSERT_ENUM(DragOperationDelete, WebDragOperationDelete);
 STATIC_ASSERT_ENUM(DragOperationEvery, WebDragOperationEvery);
 
 static bool shouldUseExternalPopupMenus = false;
 
 namespace {
 
-class UserGestureNotifier {
- public:
-  // If a UserGestureIndicator is created for a user gesture since the last
-  // page load and *userGestureObserved is false, the UserGestureNotifier
-  // will notify the client and set *userGestureObserved to true.
-  UserGestureNotifier(WebLocalFrameImpl*, bool* userGestureObserved);
-  ~UserGestureNotifier();
-
- private:
-  Persistent<WebLocalFrameImpl> m_frame;
-  bool* const m_userGestureObserved;
-};
-
-UserGestureNotifier::UserGestureNotifier(WebLocalFrameImpl* frame,
-                                         bool* userGestureObserved)
-    : m_frame(frame), m_userGestureObserved(userGestureObserved) {
-  DCHECK(m_userGestureObserved);
-}
-
-UserGestureNotifier::~UserGestureNotifier() {
-  if (!*m_userGestureObserved &&
-      m_frame->frame()->document()->hasReceivedUserGesture()) {
-    *m_userGestureObserved = true;
-    if (m_frame && m_frame->autofillClient())
-      m_frame->autofillClient()->firstUserGestureObserved();
-  }
-}
-
 class EmptyEventListener final : public EventListener {
  public:
   static EmptyEventListener* create() { return new EmptyEventListener(); }
 
   bool operator==(const EventListener& other) const override {
     return this == &other;
   }
 
  private:
   EmptyEventListener() : EventListener(CPPEventListenerType) {}
@@ skipping 105 matching lines @@
       m_doubleTapZoomPageScaleFactor(0),
       m_doubleTapZoomPending(false),
       m_enableFakePageScaleAnimationForTesting(false),
       m_fakePageScaleAnimationPageScaleFactor(0),
       m_fakePageScaleAnimationUseAnchor(false),
       m_doingDragAndDrop(false),
       m_ignoreInputEvents(false),
       m_compositorDeviceScaleFactorOverride(0),
       m_suppressNextKeypressEvent(false),
       m_imeAcceptEvents(true),
-      m_operationsAllowed(WebDragOperationNone),
-      m_dragOperation(WebDragOperationNone),
       m_devToolsEmulator(nullptr),
       m_isTransparent(false),
       m_tabsToLinks(false),
       m_layerTreeView(nullptr),
       m_rootLayer(nullptr),
       m_rootGraphicsLayer(nullptr),
       m_visualViewportContainerLayer(nullptr),
       m_matchesHeuristicsForGpuRasterization(false),
       m_flingModifier(0),
       m_flingSourceDevice(WebGestureDeviceUninitialized),
@@ skipping 51 matching lines @@
 
 WebViewImpl::~WebViewImpl() {
   DCHECK(!m_page);
 
   // Each highlight uses m_owningWebViewImpl->m_linkHighlightsTimeline
   // in destructor. m_linkHighlightsTimeline might be destroyed earlier
   // than m_linkHighlights.
   DCHECK(m_linkHighlights.isEmpty());
 }
 
+WebViewImpl::UserGestureNotifier::UserGestureNotifier(WebViewImpl* view)
+    : m_frame(view->mainFrameImpl()),
+      m_userGestureObserved(&view->m_userGestureObserved) {
+  DCHECK(m_userGestureObserved);
+}
+
+WebViewImpl::UserGestureNotifier::~UserGestureNotifier() {
+  if (!*m_userGestureObserved &&
+      m_frame->frame()->document()->hasReceivedUserGesture()) {
+    *m_userGestureObserved = true;
+    if (m_frame && m_frame->autofillClient())
+      m_frame->autofillClient()->firstUserGestureObserved();
+  }
+}
+
 WebDevToolsAgentImpl* WebViewImpl::mainFrameDevToolsAgentImpl() {
   WebLocalFrameImpl* mainFrame = mainFrameImpl();
   return mainFrame ? mainFrame->devToolsAgentImpl() : nullptr;
 }
 
 InspectorOverlay* WebViewImpl::inspectorOverlay() {
   if (WebDevToolsAgentImpl* devtools = mainFrameDevToolsAgentImpl())
     return devtools->overlay();
   return nullptr;
 }
@@ skipping 1635 matching lines @@
 
 WebInputEventResult WebViewImpl::handleInputEvent(
     const WebInputEvent& inputEvent) {
   // TODO(dcheng): The fact that this is getting called when there is no local
   // main frame is problematic and probably indicates a bug in the input event
   // routing code.
   if (!mainFrameImpl())
     return WebInputEventResult::NotHandled;
 
   WebAutofillClient* autofillClient = mainFrameImpl()->autofillClient();
-  UserGestureNotifier notifier(mainFrameImpl(), &m_userGestureObserved);
+  UserGestureNotifier notifier(this);
   // On the first input event since page load, |notifier| instructs the
   // autofill client to unblock values of password input fields of any forms
   // on the page. There is a single input event, GestureTap, which can both
   // be the first event after page load, and cause a form submission. In that
   // case, the form submission happens before the autofill client is told
   // to unblock the password values, and so the password values are not
   // submitted. To avoid that, GestureTap is handled explicitly:
   if (inputEvent.type == WebInputEvent::GestureTap && autofillClient) {
     m_userGestureObserved = true;
     autofillClient->firstUserGestureObserved();
@@ skipping 1278 matching lines @@
 
 void WebViewImpl::dragSourceSystemDragEnded() {
   // It's possible for us to get this callback while not doing a drag if
   // it's from a previous page that got unloaded.
   if (m_doingDragAndDrop) {
     m_page->dragController().dragEnded();
     m_doingDragAndDrop = false;
   }
 }
 
-WebDragOperation WebViewImpl::dragTargetDragEnter(
-    const WebDragData& webDragData,
-    const WebPoint& pointInViewport,
-    const WebPoint& screenPoint,
-    WebDragOperationsMask operationsAllowed,
-    int modifiers) {
-  DCHECK(!m_currentDragData);
-
-  m_currentDragData = DataObject::create(webDragData);
-  m_operationsAllowed = operationsAllowed;
-
-  return dragTargetDragEnterOrOver(pointInViewport, screenPoint, DragEnter,
-                                   modifiers);
-}
-
-WebDragOperation WebViewImpl::dragTargetDragOver(
-    const WebPoint& pointInViewport,
-    const WebPoint& screenPoint,
-    WebDragOperationsMask operationsAllowed,
-    int modifiers) {
-  m_operationsAllowed = operationsAllowed;
-
-  return dragTargetDragEnterOrOver(pointInViewport, screenPoint, DragOver,
-                                   modifiers);
-}
-
-void WebViewImpl::dragTargetDragLeave() {
-  DCHECK(m_currentDragData);
-
-  DragData dragData(m_currentDragData.get(), IntPoint(), IntPoint(),
-                    static_cast<DragOperation>(m_operationsAllowed));
-
-  m_page->dragController().dragExited(&dragData);
-
-  // FIXME: why is the drag scroll timer not stopped here?
-
-  m_dragOperation = WebDragOperationNone;
-  m_currentDragData = nullptr;
-}
-
-void WebViewImpl::dragTargetDrop(const WebDragData& webDragData,
-                                 const WebPoint& pointInViewport,
-                                 const WebPoint& screenPoint,
-                                 int modifiers) {
-  WebPoint pointInRootFrame(
-      page()->frameHost().visualViewport().viewportToRootFrame(
-          pointInViewport));
-
-  DCHECK(m_currentDragData);
-  m_currentDragData = DataObject::create(webDragData);
-  UserGestureNotifier notifier(mainFrameImpl(), &m_userGestureObserved);
-
-  // If this webview transitions from the "drop accepting" state to the "not
-  // accepting" state, then our IPC message reply indicating that may be in-
-  // flight, or else delayed by javascript processing in this webview.  If a
-  // drop happens before our IPC reply has reached the browser process, then
-  // the browser forwards the drop to this webview.  So only allow a drop to
-  // proceed if our webview m_dragOperation state is not DragOperationNone.
-
-  if (m_dragOperation ==
-      WebDragOperationNone) {  // IPC RACE CONDITION: do not allow this drop.
-    dragTargetDragLeave();
-    return;
-  }
-
-  m_currentDragData->setModifiers(modifiers);
-  DragData dragData(m_currentDragData.get(), pointInRootFrame, screenPoint,
-                    static_cast<DragOperation>(m_operationsAllowed));
-
-  m_page->dragController().performDrag(&dragData);
-
-  m_dragOperation = WebDragOperationNone;
-  m_currentDragData = nullptr;
-}
-
 void WebViewImpl::spellingMarkers(WebVector<uint32_t>* markers) {
   Vector<uint32_t> result;
   for (Frame* frame = m_page->mainFrame(); frame;
        frame = frame->tree().traverseNext()) {
     if (!frame->isLocalFrame())
       continue;
     const DocumentMarkerVector& documentMarkers =
         toLocalFrame(frame)->document()->markers().markers();
     for (size_t i = 0; i < documentMarkers.size(); ++i)
       result.append(documentMarkers[i]->hash());
   }
   markers->assign(result);
 }
 
 void WebViewImpl::removeSpellingMarkersUnderWords(
     const WebVector<WebString>& words) {
   Vector<String> convertedWords;
   convertedWords.append(words.data(), words.size());
 
   for (Frame* frame = m_page->mainFrame(); frame;
        frame = frame->tree().traverseNext()) {
     if (frame->isLocalFrame())
       toLocalFrame(frame)->removeSpellingMarkersUnderWords(convertedWords);
   }
 }
 
-WebDragOperation WebViewImpl::dragTargetDragEnterOrOver(
-    const WebPoint& pointInViewport,
-    const WebPoint& screenPoint,
-    DragAction dragAction,
-    int modifiers) {
-  DCHECK(m_currentDragData);
-
-  WebPoint pointInRootFrame(
-      page()->frameHost().visualViewport().viewportToRootFrame(
-          pointInViewport));
-
-  m_currentDragData->setModifiers(modifiers);
-  DragData dragData(m_currentDragData.get(), pointInRootFrame, screenPoint,
-                    static_cast<DragOperation>(m_operationsAllowed));
-
-  DragSession dragSession;
-  dragSession = m_page->dragController().dragEnteredOrUpdated(&dragData);
-
-  DragOperation dropEffect = dragSession.operation;
-
-  // Mask the drop effect operation against the drag source's allowed
-  // operations.
-  if (!(dropEffect & dragData.draggingSourceOperationMask()))
-    dropEffect = DragOperationNone;
-
-  m_dragOperation = static_cast<WebDragOperation>(dropEffect);
-
-  return m_dragOperation;
-}
-
 void WebViewImpl::sendResizeEventAndRepaint() {
   // FIXME: This is wrong. The FrameView is responsible sending a resizeEvent
   // as part of layout. Layout is also responsible for sending invalidations
   // to the embedder. This method and all callers may be wrong. -- eseidel.
   if (mainFrameImpl()->frameView()) {
     // Enqueues the resize event.
     mainFrameImpl()->frame()->document()->enqueueResizeEvent();
   }
 
   if (m_client) {
@@ skipping 785 matching lines @@
   if (focusedFrame->localFrameRoot() != mainFrameImpl()->frame())
     return nullptr;
   return focusedFrame;
 }
 
 LocalFrame* WebViewImpl::focusedLocalFrameAvailableForIme() const {
   return m_imeAcceptEvents ? focusedLocalFrameInWidget() : nullptr;
 }
 
 }  // namespace blink