Changeset 265088 in webkit

Timestamp:

Jul 30, 2020 10:12:33 AM (4 years ago)

Author:

graouts@webkit.org

Message:

[iOS] Unable to swipe on IMDB.com after long press on image
​https://bugs.webkit.org/show_bug.cgi?id=214968
<rdar://problem/66234421>

Reviewed by Wenson Hsieh.

Source/WebCore:

When a long press occurs on an <img>, a system drag interaction is initiated on iOS. In WebCore,
EventHandler::tryToBeginDragAtPoint() is called and a synthetic mouse event is produced, causing
handleMousePressEvent() to be called. Further down the call chain, dispatchPointerEventIfNeeded()
is called and a valid PointerEvent is generated in PointerCaptureController::pointerEventForMouseEvent()
with "pointerType" set to "mouse", even though there is already a touch interaction initiated.

We now check whether there are known touches before generating a PointerEvent for a MouseEvent.

In the case of IMDb, the page would keep track of "pointerdown" events to track whether a multi-touch
user gesture is in progress so that their slide shows can support two-finger zooming as well as
single-finger swiping. In the case of a long press, the second "pointerdown" event would trick
the code in thinking a zoom gesture was initiated and it never recovered.

Test: pointerevents/ios/long-press-yields-single-pointerdown-event.html

• page/PointerCaptureController.cpp:

(WebCore::PointerCaptureController::pointerEventForMouseEvent):

LayoutTests:

Add a test that triggers a long press gesture on an <img> and checks a single "pointerdown" event
was dispatched. Prior to the WebCore change in this patch, two events would be dispatched.

• pointerevents/ios/long-press-yields-single-pointerdown-event-expected.txt: Added.
• pointerevents/ios/long-press-yields-single-pointerdown-event.html: Added.

Location:

trunk

Files:

• LayoutTests/ChangeLog (modified) (1 diff)
• LayoutTests/pointerevents/ios/long-press-yields-single-pointerdown-event-expected.txt (added)
• LayoutTests/pointerevents/ios/long-press-yields-single-pointerdown-event.html (added)
• Source/WebCore/ChangeLog (modified) (1 diff)
• Source/WebCore/page/PointerCaptureController.cpp (modified) (1 diff)

trunk/LayoutTests/ChangeLog

@@ +1 @@
+2020-07-30  Antoine Quint  <graouts@webkit.org>
+
+        [iOS] Unable to swipe on IMDB.com after long press on image
+        https://bugs.webkit.org/show_bug.cgi?id=214968
+        <rdar://problem/66234421>
+
+        Reviewed by Wenson Hsieh.
+
+        Add a test that triggers a long press gesture on an <img> and checks a single "pointerdown" event
+        was dispatched. Prior to the WebCore change in this patch, two events would be dispatched.
+
+        * pointerevents/ios/long-press-yields-single-pointerdown-event-expected.txt: Added.
+        * pointerevents/ios/long-press-yields-single-pointerdown-event.html: Added.
+
 2020-07-30  Hector Lopez  <hector_i_lopez@apple.com>
 

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2020-07-30  Antoine Quint  <graouts@webkit.org>
+
+        [iOS] Unable to swipe on IMDB.com after long press on image
+        https://bugs.webkit.org/show_bug.cgi?id=214968
+        <rdar://problem/66234421>
+
+        Reviewed by Wenson Hsieh.
+
+        When a long press occurs on an <img>, a system drag interaction is initiated on iOS. In WebCore,
+        EventHandler::tryToBeginDragAtPoint() is called and a synthetic mouse event is produced, causing
+        handleMousePressEvent() to be called. Further down the call chain, dispatchPointerEventIfNeeded()
+        is called and a valid PointerEvent is generated in PointerCaptureController::pointerEventForMouseEvent()
+        with "pointerType" set to "mouse", even though there is already a touch interaction initiated.
+
+        We now check whether there are known touches before generating a PointerEvent for a MouseEvent.
+
+        In the case of IMDb, the page would keep track of "pointerdown" events to track whether a multi-touch
+        user gesture is in progress so that their slide shows can support two-finger zooming as well as
+        single-finger swiping. In the case of a long press, the second "pointerdown" event would trick
+        the code in thinking a zoom gesture was initiated and it never recovered.
+
+        Test: pointerevents/ios/long-press-yields-single-pointerdown-event.html
+
+        * page/PointerCaptureController.cpp:
+        (WebCore::PointerCaptureController::pointerEventForMouseEvent):
+
 2020-07-30  Chris Dumez  <cdumez@apple.com>
 

trunk/Source/WebCore/page/PointerCaptureController.cpp

@@ -302 +302 @@
 RefPtr<PointerEvent> PointerCaptureController::pointerEventForMouseEvent(const MouseEvent& mouseEvent)
 {
+    // If we already have known touches then we cannot dispatch a mouse event,
+    // for instance in the case of a long press to initiate a system drag.
+    for (auto& capturingData : m_activePointerIdsToCapturingData.values()) {
+        if (capturingData.pointerType != PointerEvent::mousePointerType())
+            return nullptr;
+    }
+
     const auto& type = mouseEvent.type();
     const auto& names = eventNames();