From 13bb87c0df7557ff796fe0bb2051cfe7aa9b93c5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Gide=C3=A3o?= <gideaoms@gmail.com>
Date: Tue, 22 Apr 2025 09:34:02 -0300
Subject: [PATCH 1/2] check if it is active

---
 src/VisibilitySensor.tsx | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/VisibilitySensor.tsx b/src/VisibilitySensor.tsx
index 1ccdae4..818feec 100644
--- a/src/VisibilitySensor.tsx
+++ b/src/VisibilitySensor.tsx
@@ -114,6 +114,8 @@ const VisibilitySensor = forwardRef<VisibilitySensorRef, VisibilitySensorProps>(
     }, [disabled, startWatching, stopWatching]);
 
     useEffect(() => {
+      if (!active) return;
+
       const window: ScaledSize = Dimensions.get('window');
       const isVisible: boolean =
         rectDimensions.rectTop + (threshold.top || 0) <= window.height && // Top edge is within the bottom of the window

From d60a41188a44d48ce038b205252ba5880d30e509 Mon Sep 17 00:00:00 2001
From: Jairaj Jangle <25704330+JairajJangle@users.noreply.github.com>
Date: Sat, 26 Apr 2025 11:06:38 +0530
Subject: [PATCH 2/2] fix: incorrect visibility state on initial render - fixes
 #30

Updates PR #33 to add more checks and added missing state in useEffect's dependency array
---
 src/VisibilitySensor.tsx | 20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/src/VisibilitySensor.tsx b/src/VisibilitySensor.tsx
index 818feec..2d48b72 100644
--- a/src/VisibilitySensor.tsx
+++ b/src/VisibilitySensor.tsx
@@ -58,8 +58,11 @@ const VisibilitySensor = forwardRef<VisibilitySensorRef, VisibilitySensorProps>(
     });
     const [lastValue, setLastValue] = useState<boolean | undefined>(undefined);
     const [active, setActive] = useState<boolean>(false);
+    const hasMeasuredRef = useRef(false);
 
     const measureInnerView = () => {
+      /* Check if the sensor is active to prevent unnecessary measurements
+      This avoids running measurements when the sensor is disabled or stopped */
       if (!active) return;
 
       localRef.current?.measure(
@@ -88,6 +91,9 @@ const VisibilitySensor = forwardRef<VisibilitySensorRef, VisibilitySensorProps>(
             rectDimensions.rectHeight !== dimensions.rectHeight
           ) {
             setRectDimensions(dimensions);
+            /* Set hasMeasuredRef to true to indicate that a valid measurement has been taken
+            This ensures visibility checks only proceed after initial measurement */
+            hasMeasuredRef.current = true;
           }
         }
       );
@@ -100,7 +106,12 @@ const VisibilitySensor = forwardRef<VisibilitySensorRef, VisibilitySensorProps>(
     }, [active]);
 
     const stopWatching = useCallback(() => {
-      if (active) setActive(false);
+      if (active) {
+        setActive(false);
+        /* Reset measurement state when stopping to ensure fresh measurements
+        when the sensor is reactivated */
+        hasMeasuredRef.current = false;
+      }
     }, [active]);
 
     useEffect(() => {
@@ -114,7 +125,10 @@ const VisibilitySensor = forwardRef<VisibilitySensorRef, VisibilitySensorProps>(
     }, [disabled, startWatching, stopWatching]);
 
     useEffect(() => {
-      if (!active) return;
+      /* Ensure visibility checks only run when the sensor is active and
+      at least one measurement has been completed. This prevents
+      premature visibility calculations with invalid or stale dimensions */
+      if (!active || !hasMeasuredRef.current) return;
 
       const window: ScaledSize = Dimensions.get('window');
       const isVisible: boolean =
@@ -131,7 +145,7 @@ const VisibilitySensor = forwardRef<VisibilitySensorRef, VisibilitySensorProps>(
         }
       }
       // eslint-disable-next-line react-hooks/exhaustive-deps
-    }, [rectDimensions, lastValue]);
+    }, [rectDimensions, lastValue, active]);
 
     return (
       <View ref={localRef} {...rest}>