Changeset 262469 in webkit

Timestamp:

Jun 2, 2020 6:50:46 PM (4 years ago)

Author:

Wenson Hsieh

Message:

Add a helper method to populate a DataTransfer before dispatching a "dragstart" event
​https://bugs.webkit.org/show_bug.cgi?id=212614
Work towards <rdar://problem/61368402>

Reviewed by Tim Horton.

Add a helper method in DragController to pre-populate the StaticPasteboard-backed DataTransfer before
dispatching the "dragstart" event. There should be no change in behavior yet, since StaticPasteboard doesn't
implement methods for writing data to the pasteboard, which this new method uses.

• page/DragController.cpp:

(WebCore::DragController::prepareForDragStart const):
(WebCore::DragController::hitTestResultForDragStart const):
(WebCore::DragController::startDrag):

• page/DragController.h:
• page/EventHandler.cpp:

(WebCore::EventHandler::dispatchDragStartEventOnSourceElement):

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• page/DragController.cpp (modified) (5 diffs)
• page/DragController.h (modified) (3 diffs)
• page/EventHandler.cpp (modified) (1 diff)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2020-06-02  Wenson Hsieh  <wenson_hsieh@apple.com>
+
+        Add a helper method to populate a DataTransfer before dispatching a "dragstart" event
+        https://bugs.webkit.org/show_bug.cgi?id=212614
+        Work towards <rdar://problem/61368402>
+
+        Reviewed by Tim Horton.
+
+        Add a helper method in DragController to pre-populate the StaticPasteboard-backed DataTransfer before
+        dispatching the "dragstart" event. There should be no change in behavior yet, since StaticPasteboard doesn't
+        implement methods for writing data to the pasteboard, which this new method uses.
+
+        * page/DragController.cpp:
+        (WebCore::DragController::prepareForDragStart const):
+        (WebCore::DragController::hitTestResultForDragStart const):
+        (WebCore::DragController::startDrag):
+        * page/DragController.h:
+        * page/EventHandler.cpp:
+        (WebCore::EventHandler::dispatchDragStartEventOnSourceElement):
+
 2020-06-02  Andres Gonzalez  <andresg_22@apple.com>
 

trunk/Source/WebCore/page/DragController.cpp

@@ -900 +900 @@
 }
 
-bool DragController::startDrag(Frame& src, const DragState& state, DragOperation srcOp, const PlatformMouseEvent& dragEvent, const IntPoint& dragOrigin, HasNonDefaultPasteboardData hasData)
-{
-    if (!src.view() || !src.contentRenderer() || !state.source)
-        return false;
-
-    Ref<Frame> protector(src);
+void DragController::prepareForDragStart(Frame& source, DragSourceAction action, Element& element, DataTransfer& dataTransfer, const IntPoint& dragOrigin) const
+{
+#if !PLATFORM(WIN)
+    Ref<Frame> protector(source);
+    auto hitTestResult = hitTestResultForDragStart(source, element, dragOrigin);
+    if (!hitTestResult)
+        return;
+
+    auto& pasteboard = dataTransfer.pasteboard();
+    auto& editor = source.editor();
+    if (action == DragSourceActionSelection) {
+        if (enclosingTextFormControl(source.selection().selection().start()))
+            pasteboard.writePlainText(editor.selectedTextForDataTransfer(), Pasteboard::CannotSmartReplace);
+        else
+            editor.writeSelectionToPasteboard(pasteboard);
+        return;
+    }
+
+    auto* image = getImage(element);
+    auto imageURL = hitTestResult->absoluteImageURL();
+    if ((action & DragSourceActionImage) && !imageURL.isEmpty() && image && !image->isNull()) {
+        editor.writeImageToPasteboard(pasteboard, element, imageURL, { });
+        return;
+    }
+
+    auto linkURL = hitTestResult->absoluteLinkURL();
+    if ((action & DragSourceActionLink) && !linkURL.isEmpty() && source.document()->securityOrigin().canDisplay(linkURL))
+        editor.copyURL(linkURL, hitTestResult->textContent().simplifyWhiteSpace(), pasteboard);
+#else
+    // FIXME: Make this work on Windows by implementing Editor::writeSelectionToPasteboard and Editor::writeImageToPasteboard.
+    UNUSED_PARAM(source);
+    UNUSED_PARAM(action);
+    UNUSED_PARAM(element);
+    UNUSED_PARAM(dataTransfer);
+    UNUSED_PARAM(dragOrigin);
+#endif
+}
+
+Optional<HitTestResult> DragController::hitTestResultForDragStart(Frame& source, Element& element, const IntPoint& location) const
+{
+    if (!source.view() || !source.contentRenderer())
+        return WTF::nullopt;
+
     constexpr OptionSet<HitTestRequest::RequestType> hitType { HitTestRequest::ReadOnly, HitTestRequest::Active, HitTestRequest::AllowChildFrameContent };
-    HitTestResult hitTestResult = src.eventHandler().hitTestResultAtPoint(dragOrigin, hitType);
-
-    bool sourceContainsHitNode = state.source->containsIncludingShadowDOM(hitTestResult.innerNode());
+    auto hitTestResult = source.eventHandler().hitTestResultAtPoint(location, hitType);
+
+    bool sourceContainsHitNode = element.containsIncludingShadowDOM(hitTestResult.innerNode());
     if (!sourceContainsHitNode) {
         // The original node being dragged isn't under the drag origin anymore... maybe it was
         // hidden or moved out from under the cursor. Regardless, we don't want to start a drag on
         // something that's not actually under the drag origin.
-        return false;
-    }
-
-    URL linkURL = hitTestResult.absoluteLinkURL();
-    URL imageURL = hitTestResult.absoluteImageURL();
+        return WTF::nullopt;
+    }
+
+    return { hitTestResult };
+}
+
+bool DragController::startDrag(Frame& src, const DragState& state, DragOperation srcOp, const PlatformMouseEvent& dragEvent, const IntPoint& dragOrigin, HasNonDefaultPasteboardData hasData)
+{
+    if (!state.source)
+        return false;
+
+    Ref<Frame> protector(src);
+    auto hitTestResult = hitTestResultForDragStart(src, *state.source, dragOrigin);
+    if (!hitTestResult)
+        return false;
+
+    auto linkURL = hitTestResult->absoluteLinkURL();
+    auto imageURL = hitTestResult->absoluteImageURL();
 
     IntPoint mouseDraggedPoint = src.view()->windowToContents(dragEvent.position());
@@ -1047 +1097 @@
                 selectElement(element);
             if (!attachmentInfo)
-                declareAndWriteDragImage(dataTransfer, element, !linkURL.isEmpty() ? linkURL : imageURL, hitTestResult.altDisplayString());
+                declareAndWriteDragImage(dataTransfer, element, !linkURL.isEmpty() ? linkURL : imageURL, hitTestResult->altDisplayString());
         }
 
@@ -1053 +1103 @@
 
         if (!dragImage)
-            doImageDrag(element, dragOrigin, hitTestResult.imageRect(), src, m_dragOffset, state, WTFMove(attachmentInfo));
+            doImageDrag(element, dragOrigin, hitTestResult->imageRect(), src, m_dragOffset, state, WTFMove(attachmentInfo));
         else {
             // DHTML defined drag image
@@ -1065 +1115 @@
         PasteboardWriterData pasteboardWriterData;
 
-        String textContentWithSimplifiedWhiteSpace = hitTestResult.textContent().simplifyWhiteSpace();
+        String textContentWithSimplifiedWhiteSpace = hitTestResult->textContent().simplifyWhiteSpace();
 
         if (hasData == HasNonDefaultPasteboardData::No) {
@@ -1079 +1129 @@
             PasteboardURL pasteboardURL;
             pasteboardURL.url = linkURL;
-            pasteboardURL.title = hitTestResult.textContent();
+            pasteboardURL.title = hitTestResult->textContent();
             dataTransfer.pasteboard().writeTrustworthyWebURLsPboardType(pasteboardURL);
         }

trunk/Source/WebCore/page/DragController.h

@@ -43 +43 @@
 class HTMLImageElement;
 class HTMLInputElement;
+class HitTestResult;
 class IntRect;
 class Page;
@@ -94 +95 @@
     WEBCORE_EXPORT void insertDroppedImagePlaceholdersAtCaret(const Vector<IntSize>& imageSizes);
 
+    void prepareForDragStart(Frame& sourceFrame, DragSourceAction, Element& sourceElement, DataTransfer&, const IntPoint& dragOrigin) const;
     bool startDrag(Frame& src, const DragState&, DragOperation srcOp, const PlatformMouseEvent& dragEvent, const IntPoint& dragOrigin, HasNonDefaultPasteboardData);
     static const IntSize& maxDragImageSize();
@@ -118 +120 @@
     void mouseMovedIntoDocument(Document*);
     bool shouldUseCachedImageForDragImage(const Image&) const;
+
+    Optional<HitTestResult> hitTestResultForDragStart(Frame&, Element&, const IntPoint&) const;
 
     void doImageDrag(Element&, const IntPoint&, const IntRect&, Frame&, IntPoint&, const DragState&, PromisedAttachmentInfo&&);

trunk/Source/WebCore/page/EventHandler.cpp

@@ -3772 +3772 @@
 bool EventHandler::dispatchDragStartEventOnSourceElement(DataTransfer& dataTransfer)
 {
+    if (auto* page = m_frame.page())
+        page->dragController().prepareForDragStart(m_frame, dragState().type, *dragState().source, dataTransfer, m_mouseDownContentsPosition);
     return !dispatchDragEvent(eventNames().dragstartEvent, *dragState().source, m_mouseDownEvent, dataTransfer) && !m_frame.selection().selection().isInPasswordField();
 }
-    
+
 static bool ExactlyOneBitSet(DragSourceAction n)
 {