Changeset 280647 in webkit

Timestamp:

Aug 4, 2021, 11:44:20 AM (5 years ago)

Author:

Wenson Hsieh

Message:

[iOS 15] "Look Up" action is sometimes missing after force pressing images
​https://bugs.webkit.org/show_bug.cgi?id=228774
rdar://78040734

Reviewed by Devin Rousso.

On iOS devices that support both 3D Touch and Visual Look Up (i.e., iPhone XS and iPhone XS Max), it's currently
possible to skip the image analysis preflight gesture entirely when showing the context menu over images in the
case where the user triggers the interaction by exceeding the force press threshold in under 100 ms (the current
delay of the image analysis long press gesture).

Mitigate this by teaching WKImageAnalysisGestureRecognizer to trigger image analysis preflight slightly ahead of
the context menu interaction when performing a force press by transitioning to Began state early under
-touchesBegan:withEvent: and -touchesMoved:withEvent:, if the touch's force exceeds a certain (relatively
low) threshold.

• UIProcess/ios/WKImageAnalysisGestureRecognizer.mm:

(-[WKImageAnalysisGestureRecognizer touchesBegan:withEvent:]):
(-[WKImageAnalysisGestureRecognizer touchesMoved:withEvent:]):
(-[WKImageAnalysisGestureRecognizer beginAfterExceedingForceThresholdIfNeeded:]):

Location:

trunk/Source/WebKit

Files:

• ChangeLog (modified) (1 diff)
• UIProcess/ios/WKImageAnalysisGestureRecognizer.mm (modified) (1 diff)

trunk/Source/WebKit/ChangeLog

@@ +1 @@
+2021-08-04  Wenson Hsieh  <wenson_hsieh@apple.com>
+
+        [iOS 15] "Look Up" action is sometimes missing after force pressing images
+        https://bugs.webkit.org/show_bug.cgi?id=228774
+        rdar://78040734
+
+        Reviewed by Devin Rousso.
+
+        On iOS devices that support both 3D Touch and Visual Look Up (i.e., iPhone XS and iPhone XS Max), it's currently
+        possible to skip the image analysis preflight gesture entirely when showing the context menu over images in the
+        case where the user triggers the interaction by exceeding the force press threshold in under 100 ms (the current
+        delay of the image analysis long press gesture).
+
+        Mitigate this by teaching WKImageAnalysisGestureRecognizer to trigger image analysis preflight slightly ahead of
+        the context menu interaction when performing a force press by transitioning to Began state early under
+        `-touchesBegan:withEvent:` and `-touchesMoved:withEvent:`, if the touch's force exceeds a certain (relatively
+        low) threshold.
+
+        * UIProcess/ios/WKImageAnalysisGestureRecognizer.mm:
+        (-[WKImageAnalysisGestureRecognizer touchesBegan:withEvent:]):
+        (-[WKImageAnalysisGestureRecognizer touchesMoved:withEvent:]):
+        (-[WKImageAnalysisGestureRecognizer beginAfterExceedingForceThresholdIfNeeded:]):
+
 2021-08-04  Per Arne  <pvollan@apple.com>
 

trunk/Source/WebKit/UIProcess/ios/WKImageAnalysisGestureRecognizer.mm

@@ -46 +46 @@
 }
 
+- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event
+{
+    [super touchesBegan:touches withEvent:event];
+
+    [self beginAfterExceedingForceThresholdIfNeeded:touches];
+}
+
+- (void)touchesMoved:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event
+{
+    [super touchesMoved:touches withEvent:event];
+
+    [self beginAfterExceedingForceThresholdIfNeeded:touches];
+}
+
+- (void)beginAfterExceedingForceThresholdIfNeeded:(NSSet<UITouch *> *)touches
+{
+    if (self.state != UIGestureRecognizerStatePossible)
+        return;
+
+    if (touches.count > 1)
+        return;
+
+    constexpr CGFloat forceThreshold = 1.5;
+    if (touches.anyObject.force < forceThreshold)
+        return;
+
+    self.state = UIGestureRecognizerStateBegan;
+}
+
 - (void)setState:(UIGestureRecognizerState)state
 {