Add key modifier properties to the PointerEvent interface

Summary:
Changelog: [iOS][Internal] - Add key modifier properties to the PointerEvent interface

This diff adds implementations of the `ctrlKey`, `shiftKey`, `altKey`, and `metaKey` properties on the PointerEvent interface for iOS.

Reviewed By: lunaleaps

Differential Revision: D37869377

fbshipit-source-id: b187bae93fbfc97b6ca1d8d9786ad85343484b3d

Author: vincentriemer

React/Fabric/RCTSurfaceTouchHandler.mm

@@ -83,6 +83,11 @@ typedef NS_ENUM(NSInteger, RCTTouchEventType) {
    */
   UIEventButtonMask buttonMask;
 
+  /*
+   * The bit mask of modifier flags in the gesture represented by the receiver.
+   */
+  UIKeyModifierFlags modifierFlags;
+
   /*
    * A component view on which the touch was begun.
    */
@@ -178,8 +183,10 @@ static void UpdateActiveTouchWithUITouch(
   activeTouch.azimuthAngle = [uiTouch azimuthAngleInView:nil];
   if (@available(iOS 13.4, *)) {
     activeTouch.buttonMask = uiEvent.buttonMask;
+    activeTouch.modifierFlags = uiEvent.modifierFlags;
   } else {
     activeTouch.buttonMask = 0;
+    activeTouch.modifierFlags = 0;
   }
 }
 
@@ -248,6 +255,21 @@ static SharedTouchEventEmitter GetTouchEmitterFromView(UIView *componentView, CG
   }
 }
 
+static void UpdatePointerEventModifierFlags(PointerEvent &event, UIKeyModifierFlags flags)
+{
+  if (@available(iOS 13.4, *)) {
+    event.ctrlKey = (flags & UIKeyModifierControl) != 0;
+    event.shiftKey = (flags & UIKeyModifierShift) != 0;
+    event.altKey = (flags & UIKeyModifierAlternate) != 0;
+    event.metaKey = (flags & UIKeyModifierCommand) != 0;
+  } else {
+    event.ctrlKey = false;
+    event.shiftKey = false;
+    event.altKey = false;
+    event.metaKey = false;
+  }
+}
+
 static PointerEvent CreatePointerEventFromActiveTouch(ActiveTouch activeTouch, RCTTouchEventType eventType)
 {
   Touch touch = activeTouch.touch;
@@ -277,6 +299,8 @@ static PointerEvent CreatePointerEventFromActiveTouch(ActiveTouch activeTouch, R
   event.detail = 0;
 
   event.buttons = ButtonMaskToButtons(activeTouch.buttonMask);
+  UpdatePointerEventModifierFlags(event, activeTouch.modifierFlags);
+
   // UIEvent's button mask for touch end events still marks the button as down
   // so this ensures it's set to 0 as per the pointer event spec
   if (eventType == RCTTouchEventTypeTouchEnd) {
@@ -294,7 +318,7 @@ static PointerEvent CreatePointerEventFromIncompleteHoverData(
     CGPoint clientLocation,
     CGPoint screenLocation,
     CGPoint offsetLocation,
-    NSTimeInterval timestamp)
+    UIKeyModifierFlags modifierFlags)
 {
   PointerEvent event = {};
   // "touch" events produced from a mouse cursor on iOS always have the ID 0 so
@@ -312,6 +336,7 @@ static PointerEvent CreatePointerEventFromIncompleteHoverData(
   event.tiltY = 0;
   event.detail = 0;
   event.buttons = 0;
+  UpdatePointerEventModifierFlags(event, modifierFlags);
   event.tangentialPressure = 0.0;
   event.twist = 0;
   return event;
@@ -695,9 +720,14 @@ - (void)hovering:(UIHoverGestureRecognizer *)recognizer API_AVAILABLE(ios(13.0))
 
   CGPoint offsetLocation = [recognizer locationInView:targetView];
 
-  NSOrderedSet *eventPathViews = GetTouchableViewsInPathToRoot(targetView);
+  UIKeyModifierFlags modifierFlags;
+  if (@available(iOS 13.4, *)) {
+    modifierFlags = recognizer.modifierFlags;
+  } else {
+    modifierFlags = 0;
+  }
 
-  NSTimeInterval timestamp = CACurrentMediaTime();
+  NSOrderedSet *eventPathViews = GetTouchableViewsInPathToRoot(targetView);
 
   BOOL hasMoveListenerInEventPath = NO;
 
@@ -707,7 +737,7 @@ - (void)hovering:(UIHoverGestureRecognizer *)recognizer API_AVAILABLE(ios(13.0))
     SharedTouchEventEmitter eventEmitter = GetTouchEmitterFromView(targetView, [recognizer locationInView:targetView]);
     if (shouldEmitOverEvent && eventEmitter != nil) {
       PointerEvent event = CreatePointerEventFromIncompleteHoverData(
-          targetView, clientLocation, screenLocation, offsetLocation, timestamp);
+          targetView, clientLocation, screenLocation, offsetLocation, modifierFlags);
       eventEmitter->onPointerOver(event);
     }
   }
@@ -730,7 +760,7 @@ - (void)hovering:(UIHoverGestureRecognizer *)recognizer API_AVAILABLE(ios(13.0))
           GetTouchEmitterFromView(componentView, [recognizer locationInView:componentView]);
       if (eventEmitter != nil) {
         PointerEvent event = CreatePointerEventFromIncompleteHoverData(
-            componentView, clientLocation, screenLocation, offsetLocation, timestamp);
+            componentView, clientLocation, screenLocation, offsetLocation, modifierFlags);
         eventEmitter->onPointerEnter(event);
       }
     }
@@ -749,7 +779,7 @@ - (void)hovering:(UIHoverGestureRecognizer *)recognizer API_AVAILABLE(ios(13.0))
     SharedTouchEventEmitter eventEmitter = GetTouchEmitterFromView(targetView, [recognizer locationInView:targetView]);
     if (eventEmitter != nil) {
       PointerEvent event = CreatePointerEventFromIncompleteHoverData(
-          targetView, clientLocation, screenLocation, offsetLocation, timestamp);
+          targetView, clientLocation, screenLocation, offsetLocation, modifierFlags);
       eventEmitter->onPointerMove(event);
     }
   }
@@ -761,7 +791,7 @@ - (void)hovering:(UIHoverGestureRecognizer *)recognizer API_AVAILABLE(ios(13.0))
         GetTouchEmitterFromView(prevTargetView, [recognizer locationInView:prevTargetView]);
     if (shouldEmitOutEvent && eventEmitter != nil) {
       PointerEvent event = CreatePointerEventFromIncompleteHoverData(
-          prevTargetView, clientLocation, screenLocation, offsetLocation, timestamp);
+          prevTargetView, clientLocation, screenLocation, offsetLocation, modifierFlags);
       eventEmitter->onPointerOut(event);
     }
   }
@@ -793,7 +823,7 @@ - (void)hovering:(UIHoverGestureRecognizer *)recognizer API_AVAILABLE(ios(13.0))
         GetTouchEmitterFromView(componentView, [recognizer locationInView:componentView]);
     if (eventEmitter != nil) {
       PointerEvent event = CreatePointerEventFromIncompleteHoverData(
-          componentView, clientLocation, screenLocation, offsetLocation, timestamp);
+          componentView, clientLocation, screenLocation, offsetLocation, modifierFlags);
       eventEmitter->onPointerLeave(event);
     }
   }

ReactCommon/react/renderer/components/view/PointerEvent.cpp

@@ -35,6 +35,10 @@ std::vector<DebugStringConvertibleObject> getDebugProps(
       {"tangentialPressure",
        getDebugDescription(pointerEvent.tangentialPressure, options)},
       {"twist", getDebugDescription(pointerEvent.twist, options)},
+      {"ctrlKey", getDebugDescription(pointerEvent.ctrlKey, options)},
+      {"shiftKey", getDebugDescription(pointerEvent.shiftKey, options)},
+      {"altKey", getDebugDescription(pointerEvent.altKey, options)},
+      {"metaKey", getDebugDescription(pointerEvent.metaKey, options)},
   };
 }
 

ReactCommon/react/renderer/components/view/PointerEvent.h

@@ -84,6 +84,22 @@ struct PointerEvent {
    * axis in degrees, with a value in the range 0 to 359.
    */
   int twist;
+  /*
+   * Returns true if the control key was down when the event was fired.
+   */
+  bool ctrlKey;
+  /*
+   * Returns true if the shift key was down when the event was fired.
+   */
+  bool shiftKey;
+  /*
+   * Returns true if the alt key was down when the event was fired.
+   */
+  bool altKey;
+  /*
+   * Returns true if the meta key was down when the event was fired.
+   */
+  bool metaKey;
 };
 
 #if RN_DEBUG_STRING_CONVERTIBLE

ReactCommon/react/renderer/components/view/TouchEventEmitter.cpp

@@ -87,6 +87,10 @@ static jsi::Value pointerEventPayload(
   object.setProperty(runtime, "buttons", event.buttons);
   object.setProperty(runtime, "tangentialPressure", event.tangentialPressure);
   object.setProperty(runtime, "twist", event.twist);
+  object.setProperty(runtime, "ctrlKey", event.ctrlKey);
+  object.setProperty(runtime, "shiftKey", event.shiftKey);
+  object.setProperty(runtime, "altKey", event.altKey);
+  object.setProperty(runtime, "metaKey", event.metaKey);
   return object;
 }