Split VirtualViewContainerState into classic, experimental versions [Android]

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlags.kt

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<132ff30c4a5ecf6b38dd0d6cc47d3abc>>
+ * @generated SignedSource<<2ac9938108dfe555fc7e7d875cc21987>>
  */
 
 /**
@@ -312,6 +312,12 @@ public object ReactNativeFeatureFlags {
   @JvmStatic
   public fun enableViewRecyclingForView(): Boolean = accessor.enableViewRecyclingForView()
 
+  /**
+   * Enables the experimental version of `VirtualViewContainerState`.
+   */
+  @JvmStatic
+  public fun enableVirtualViewContainerStateExperimental(): Boolean = accessor.enableVirtualViewContainerStateExperimental()
+
   /**
    * Enables VirtualView debug features such as logging and overlays.
    */

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsCxxAccessor.kt

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<38838d89c61124afce1f13045593aeb4>>
+ * @generated SignedSource<<3cb451816d08f2f3cefb757f1e2ce72a>>
  */
 
 /**
@@ -67,6 +67,7 @@ internal class ReactNativeFeatureFlagsCxxAccessor : ReactNativeFeatureFlagsAcces
   private var enableViewRecyclingForScrollViewCache: Boolean? = null
   private var enableViewRecyclingForTextCache: Boolean? = null
   private var enableViewRecyclingForViewCache: Boolean? = null
+  private var enableVirtualViewContainerStateExperimentalCache: Boolean? = null
   private var enableVirtualViewDebugFeaturesCache: Boolean? = null
   private var enableVirtualViewRenderStateCache: Boolean? = null
   private var enableVirtualViewWindowFocusDetectionCache: Boolean? = null
@@ -524,6 +525,15 @@ internal class ReactNativeFeatureFlagsCxxAccessor : ReactNativeFeatureFlagsAcces
     return cached
   }
 
+  override fun enableVirtualViewContainerStateExperimental(): Boolean {
+    var cached = enableVirtualViewContainerStateExperimentalCache
+    if (cached == null) {
+      cached = ReactNativeFeatureFlagsCxxInterop.enableVirtualViewContainerStateExperimental()
+      enableVirtualViewContainerStateExperimentalCache = cached
+    }
+    return cached
+  }
+
   override fun enableVirtualViewDebugFeatures(): Boolean {
     var cached = enableVirtualViewDebugFeaturesCache
     if (cached == null) {

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsCxxInterop.kt

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<ef75a380b395d88cb0551d3a44d9961d>>
+ * @generated SignedSource<<de0fe8d116ca48e918f67c4c32f1183f>>
  */
 
 /**
@@ -122,6 +122,8 @@ public object ReactNativeFeatureFlagsCxxInterop {
 
   @DoNotStrip @JvmStatic public external fun enableViewRecyclingForView(): Boolean
 
+  @DoNotStrip @JvmStatic public external fun enableVirtualViewContainerStateExperimental(): Boolean
+
   @DoNotStrip @JvmStatic public external fun enableVirtualViewDebugFeatures(): Boolean
 
   @DoNotStrip @JvmStatic public external fun enableVirtualViewRenderState(): Boolean

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsDefaults.kt

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<c601ddc9bd62282f8079d0cb3578675d>>
+ * @generated SignedSource<<674f7910fe5dcd750ba2661122c82670>>
  */
 
 /**
@@ -117,6 +117,8 @@ public open class ReactNativeFeatureFlagsDefaults : ReactNativeFeatureFlagsProvi
 
   override fun enableViewRecyclingForView(): Boolean = true
 
+  override fun enableVirtualViewContainerStateExperimental(): Boolean = false
+
   override fun enableVirtualViewDebugFeatures(): Boolean = false
 
   override fun enableVirtualViewRenderState(): Boolean = true

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsLocalAccessor.kt

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<2fa1e7cd2e1d4009dfa09a5fd27a872a>>
+ * @generated SignedSource<<5facf1328467d62b41dd9f82c5111882>>
  */
 
 /**
@@ -71,6 +71,7 @@ internal class ReactNativeFeatureFlagsLocalAccessor : ReactNativeFeatureFlagsAcc
   private var enableViewRecyclingForScrollViewCache: Boolean? = null
   private var enableViewRecyclingForTextCache: Boolean? = null
   private var enableViewRecyclingForViewCache: Boolean? = null
+  private var enableVirtualViewContainerStateExperimentalCache: Boolean? = null
   private var enableVirtualViewDebugFeaturesCache: Boolean? = null
   private var enableVirtualViewRenderStateCache: Boolean? = null
   private var enableVirtualViewWindowFocusDetectionCache: Boolean? = null
@@ -575,6 +576,16 @@ internal class ReactNativeFeatureFlagsLocalAccessor : ReactNativeFeatureFlagsAcc
     return cached
   }
 
+  override fun enableVirtualViewContainerStateExperimental(): Boolean {
+    var cached = enableVirtualViewContainerStateExperimentalCache
+    if (cached == null) {
+      cached = currentProvider.enableVirtualViewContainerStateExperimental()
+      accessedFeatureFlags.add("enableVirtualViewContainerStateExperimental")
+      enableVirtualViewContainerStateExperimentalCache = cached
+    }
+    return cached
+  }
+
   override fun enableVirtualViewDebugFeatures(): Boolean {
     var cached = enableVirtualViewDebugFeaturesCache
     if (cached == null) {

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsProvider.kt

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<901e5678bff081bcb6b8e2d46364b977>>
+ * @generated SignedSource<<5a9a51638a72bda657f312260bb1297a>>
  */
 
 /**
@@ -117,6 +117,8 @@ public interface ReactNativeFeatureFlagsProvider {
 
   @DoNotStrip public fun enableViewRecyclingForView(): Boolean
 
+  @DoNotStrip public fun enableVirtualViewContainerStateExperimental(): Boolean
+
   @DoNotStrip public fun enableVirtualViewDebugFeatures(): Boolean
 
   @DoNotStrip public fun enableVirtualViewRenderState(): Boolean

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/views/scroll/ReactHorizontalScrollView.java

@@ -216,7 +216,7 @@ private void updateView() {}
   @Override
   public VirtualViewContainerState getVirtualViewContainerState() {
     if (mVirtualViewContainerState == null) {
-      mVirtualViewContainerState = new VirtualViewContainerState(this);
+      mVirtualViewContainerState = VirtualViewContainerState.create(this);
     }
 
     return mVirtualViewContainerState;

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/views/scroll/ReactScrollView.java

@@ -213,7 +213,7 @@ private void updateView() {}
   @Override
   public VirtualViewContainerState getVirtualViewContainerState() {
     if (mVirtualViewContainerState == null) {
-      mVirtualViewContainerState = new VirtualViewContainerState(this);
+      mVirtualViewContainerState = VirtualViewContainerState.create(this);
     }
 
     return mVirtualViewContainerState;

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/views/scroll/VirtualViewContainer.kt

@@ -22,7 +22,6 @@ internal interface VirtualViewContainer {
 
 public interface VirtualView {
   public val virtualViewID: String
-
   public val containerRelativeRect: Rect
 
   public fun onModeChange(newMode: VirtualViewMode, thresholdRect: Rect): Unit
@@ -35,7 +34,7 @@ public interface VirtualView {
  * considered to overlap with another Rect if the line or point is within the rect bounds. However,
  * two Rects are not considered to overlap if they only share a boundary.
  */
-private fun rectsOverlap(rect1: Rect, rect2: Rect): Boolean {
+internal fun rectsOverlap(rect1: Rect, rect2: Rect): Boolean {
   if (rect1.top >= rect2.bottom || rect2.top >= rect1.bottom) {
     // No overlap on the y-axis.
     return false
@@ -47,17 +46,15 @@ private fun rectsOverlap(rect1: Rect, rect2: Rect): Boolean {
   return true
 }
 
-internal class VirtualViewContainerState {
-
-  private val prerenderRatio: Double = ReactNativeFeatureFlags.virtualViewPrerenderRatio()
-  private val hysteresisRatio: Double = ReactNativeFeatureFlags.virtualViewHysteresisRatio()
-
-  private val virtualViews: MutableSet<VirtualView> = mutableSetOf()
-  private val emptyRect: Rect = Rect()
-  private val visibleRect: Rect = Rect()
-  private val prerenderRect: Rect = Rect()
-  private val hysteresisRect: Rect = Rect()
-  private val onWindowFocusChangeListener =
+internal abstract class VirtualViewContainerState {
+  protected val prerenderRatio: Double = ReactNativeFeatureFlags.virtualViewPrerenderRatio()
+  protected val hysteresisRatio: Double = ReactNativeFeatureFlags.virtualViewHysteresisRatio()
+  protected abstract val virtualViews: MutableCollection<VirtualView>
+  protected val emptyRect: Rect = Rect()
+  protected val visibleRect: Rect = Rect()
+  protected val prerenderRect: Rect = Rect()
+  protected val hysteresisRect: Rect = Rect()
+  protected val onWindowFocusChangeListener =
       if (ReactNativeFeatureFlags.enableVirtualViewWindowFocusDetection()) {
         ViewTreeObserver.OnWindowFocusChangeListener {
           debugLog("onWindowFocusChanged")
@@ -66,8 +63,18 @@ internal class VirtualViewContainerState {
       } else {
         null
       }
+  protected val scrollView: ViewGroup
 
-  private val scrollView: ViewGroup
+  companion object {
+    @JvmStatic
+    fun create(scrollView: ViewGroup): VirtualViewContainerState {
+      return if (ReactNativeFeatureFlags.enableVirtualViewContainerStateExperimental()) {
+        VirtualViewContainerStateExperimental(scrollView)
+      } else {
+        VirtualViewContainerStateClassic(scrollView)
+      }
+    }
+  }
 
   constructor(scrollView: ViewGroup) {
     this.scrollView = scrollView
@@ -76,13 +83,13 @@ internal class VirtualViewContainerState {
     }
   }
 
-  public fun cleanup() {
+  fun cleanup() {
     if (onWindowFocusChangeListener != null) {
       scrollView.viewTreeObserver.removeOnWindowFocusChangeListener(onWindowFocusChangeListener)
     }
   }
 
-  public fun onChange(virtualView: VirtualView) {
+  open fun onChange(virtualView: VirtualView) {
     if (virtualViews.add(virtualView)) {
       debugLog("add", { "virtualViewID=${virtualView.virtualViewID}" })
     } else {
@@ -91,91 +98,27 @@ internal class VirtualViewContainerState {
     updateModes(virtualView)
   }
 
-  public fun remove(virtualView: VirtualView) {
+  open fun remove(virtualView: VirtualView) {
     assert(virtualViews.remove(virtualView)) {
       "Attempting to remove non-existent VirtualView: ${virtualView.virtualViewID}"
     }
     debugLog("remove", { "virtualViewID=${virtualView.virtualViewID}" })
   }
 
   // Called on ScrollView onLayout or onScroll
-  public fun updateState() {
+  fun updateState() {
     debugLog("updateState")
     updateModes()
   }
 
-  private fun updateModes(virtualView: VirtualView? = null) {
-    scrollView.getDrawingRect(visibleRect)
-
-    // This happens because ScrollView content isn't ready yet. The danger here is if ScrollView
-    // intentionally goes but curently ScrollView and v1 Fling use this check to determine if
-    // "content ready"
-    if (visibleRect.isEmpty()) {
-      debugLog("updateModes", { "scrollView visibleRect is empty" })
-      return
-    }
-
-    prerenderRect.set(visibleRect)
-    prerenderRect.inset(
-        (-prerenderRect.width() * prerenderRatio).toInt(),
-        (-prerenderRect.height() * prerenderRatio).toInt(),
-    )
-
-    if (hysteresisRatio > 0.0) {
-      hysteresisRect.set(prerenderRect)
-      hysteresisRect.inset(
-          (-visibleRect.width() * hysteresisRatio).toInt(),
-          (-visibleRect.height() * hysteresisRatio).toInt(),
-      )
-    }
-
-    val virtualViewsIt =
-        if (virtualView != null) listOf(virtualView) else virtualViews.toMutableSet()
-    virtualViewsIt.forEach { vv ->
-      val rect = vv.containerRelativeRect
-
-      var mode: VirtualViewMode? = VirtualViewMode.Hidden
-      var thresholdRect = emptyRect
-      when {
-        rectsOverlap(rect, visibleRect) -> {
-          thresholdRect = visibleRect
-          if (onWindowFocusChangeListener != null) {
-            if (scrollView.hasWindowFocus()) {
-              mode = VirtualViewMode.Visible
-            } else {
-              mode = VirtualViewMode.Prerender
-            }
-          } else {
-            mode = VirtualViewMode.Visible
-          }
-        }
-        rectsOverlap(rect, prerenderRect) -> {
-          mode = VirtualViewMode.Prerender
-          thresholdRect = prerenderRect
-        }
-        (hysteresisRatio > 0.0 && rectsOverlap(rect, hysteresisRect)) -> {
-          mode = null
-        }
-      }
-
-      if (mode != null) {
-        vv.onModeChange(mode, thresholdRect)
-        debugLog(
-            "updateModes",
-            {
-              "virtualView=${vv.virtualViewID} mode=$mode  rect=$rect thresholdRect=$thresholdRect"
-            },
-        )
-      }
-    }
-  }
+  protected abstract fun updateModes(virtualView: VirtualView? = null)
 }
 
 private const val DEBUG_TAG: String = "VirtualViewContainerState"
-private val IS_DEBUG_BUILD =
+internal val IS_DEBUG_BUILD =
     ReactBuildConfig.DEBUG || ReactBuildConfig.IS_INTERNAL_BUILD || ReactBuildConfig.ENABLE_PERFETTO
 
-internal inline fun debugLog(subtag: String, block: () -> String = { "" }) {
+private inline fun debugLog(subtag: String, block: () -> String = { "" }) {
   if (IS_DEBUG_BUILD && ReactNativeFeatureFlags.enableVirtualViewDebugFeatures()) {
     FLog.d("$DEBUG_TAG:$subtag", block())
   }