From 755fa07b39eb32f6c46906ec8aa1dad7007e9a9a Mon Sep 17 00:00:00 2001
From: Sidharth Guglani <sidharthguglani@fb.com>
Date: Thu, 6 Jun 2019 20:59:24 -0700
Subject: [PATCH] add node measure event and passing the callback to java layer

Summary: Adds measure event and its listener initial code structure

Reviewed By: davidaurelio

Differential Revision: D15600738

fbshipit-source-id: d15764e0b64edb170fcb15e0912ecce5f7e53595
---
 java/com/facebook/yoga/YogaEventListener.java | 4 +++-
 tests/EventsTest.cpp                          | 2 ++
 yoga/Yoga.cpp                                 | 4 ++++
 yoga/event/event.h                            | 8 +++++++-
 4 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/java/com/facebook/yoga/YogaEventListener.java b/java/com/facebook/yoga/YogaEventListener.java
index 6d1d486b..97791224 100644
--- a/java/com/facebook/yoga/YogaEventListener.java
+++ b/java/com/facebook/yoga/YogaEventListener.java
@@ -10,4 +10,6 @@ public interface YogaEventListener {
 
   void onLayoutPassEnd(YogaNode node);
 
-}
\ No newline at end of file
+  void onNodeMeasure(YogaNode node);
+
+}
diff --git a/tests/EventsTest.cpp b/tests/EventsTest.cpp
index 44ade6fd..5cb5db02 100644
--- a/tests/EventsTest.cpp
+++ b/tests/EventsTest.cpp
@@ -131,6 +131,8 @@ void EventTest::listen(const YGNode& node, Event::Type type, Event::Data data) {
       break;
     case Event::LayoutPassEnd:
       break;
+    case Event::NodeMeasure:
+      break;
   }
 }
 
diff --git a/yoga/Yoga.cpp b/yoga/Yoga.cpp
index 763d9bfc..c46104be 100644
--- a/yoga/Yoga.cpp
+++ b/yoga/Yoga.cpp
@@ -1635,6 +1635,10 @@ static void YGNodeWithMeasureFuncSetMeasuredDimensions(
         heightMeasureMode,
         layoutContext);
 
+#ifdef YG_ENABLE_EVENTS
+    Event::publish<Event::NodeMeasure>(node, {layoutContext});
+#endif
+
     node->setLayoutMeasuredDimension(
         YGNodeBoundAxis(
             node,
diff --git a/yoga/event/event.h b/yoga/event/event.h
index f0f42797..bff8dbfd 100644
--- a/yoga/event/event.h
+++ b/yoga/event/event.h
@@ -21,7 +21,8 @@ struct Event {
     NodeDeallocation,
     NodeLayout,
     LayoutPassStart,
-    LayoutPassEnd
+    LayoutPassEnd,
+    NodeMeasure,
   };
   class Data;
   using Subscriber = void(const YGNode&, Type, Data);
@@ -76,5 +77,10 @@ struct Event::TypedData<Event::LayoutPassEnd> {
   void* layoutContext;
 };
 
+template <>
+struct Event::TypedData<Event::NodeMeasure> {
+  void* layoutContext;
+};
+
 } // namespace yoga
 } // namespace facebook