feat: implement android files

Author: bang9

android/build.gradle

@@ -74,6 +74,7 @@ dependencies {
   //noinspection GradleDynamicVersion
   implementation "com.facebook.react:react-native:+"
   implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
+  implementation "org.jetbrains.kotlin:kotlin-reflect:$kotlin_version"
 }
 
 if (isNewArchitectureEnabled()) {

android/src/main/java/com/scrollviewenhancer/EnhancerFragment.kt

@@ -7,18 +7,20 @@
 package com.scrollviewenhancer
 
 import android.graphics.Rect
+import android.util.Log
 import android.view.View
 import com.facebook.infer.annotation.Assertions
 import com.facebook.react.bridge.*
+import com.facebook.react.uimanager.ReactShadowNode
+import com.facebook.react.uimanager.UIImplementation.LayoutUpdateListener
 import com.facebook.react.uimanager.UIManagerHelper
-import com.facebook.react.uimanager.common.ViewUtil
-import com.facebook.react.views.scroll.ReactHorizontalScrollView
+import com.facebook.react.uimanager.UIManagerModule
 import com.facebook.react.views.scroll.ReactScrollView
 import com.facebook.react.views.view.ReactViewGroup
 import java.lang.ref.WeakReference
 
 
-abstract class MaintainVisibleScrollPositionHelper {
+abstract class MVCPHelper {
   class Config internal constructor(
     val minIndexForVisible: Int,
     val autoScrollToTopThreshold: Int?
@@ -37,9 +39,9 @@ abstract class MaintainVisibleScrollPositionHelper {
   fun setConfig(config: Config?) {
     mConfig = config
   }
-  abstract fun start(): Unit
-  abstract fun stop(): Unit
-  abstract fun updateScrollPosition(): Unit
+  abstract fun start()
+  abstract fun stop()
+  abstract fun updateScrollPosition()
 }
 
 
@@ -48,173 +50,54 @@ abstract class MaintainVisibleScrollPositionHelper {
  *
  * This uses UIManager to listen to updates and capture position of items before and after layout.
  */
-class MaintainVisibleScrollPositionHelperV(
+class MaintainVisibleScrollPositionHelper(
   private val mScrollView: ReactScrollView,
   private val mHorizontal: Boolean = false
-): UIManagerListener, MaintainVisibleScrollPositionHelper() {
+): MVCPHelper(), UIManagerListener, LayoutUpdateListener {
   private var mFirstVisibleView: WeakReference<View>? = null
   private var mPrevFirstVisibleFrame: Rect? = null
   private var mListening: Boolean = false
 
-  /**
-   * Start listening to view hierarchy updates. Should be called when this is created.
-   */
-  override fun start() {
-    if (mListening) {
-      return
-    }
-    mListening = true
-    uIManagerModule.addUIManagerEventListener(this)
-  }
-
-  /**
-   * Stop listening to view hierarchy updates. Should be called before this is destroyed.
-   */
-  override fun stop() {
-    if (!mListening) {
-      return
-    }
-    mListening = false
-    uIManagerModule.removeUIManagerEventListener(this)
-  }
+  private val contentView: ReactViewGroup?
+    get() = mScrollView.getChildAt(0) as? ReactViewGroup
 
-  /**
-   * Update the scroll position of the managed ScrollView. This should be called after layout
-   * has been updated.
-   */
-  override fun updateScrollPosition() {
-    if ((mConfig == null
-        ) || (mFirstVisibleView == null
-        ) || (mPrevFirstVisibleFrame == null)
-    ) {
-      return
-    }
-    val firstVisibleView: View? = mFirstVisibleView!!.get()
-    val newFrame: Rect = Rect()
-    firstVisibleView!!.getHitRect(newFrame)
-    if (mHorizontal) {
-      val deltaX: Int = newFrame.left - mPrevFirstVisibleFrame!!.left
-      if (deltaX != 0) {
-        val scrollX: Int = mScrollView.scrollX
-        mScrollView.scrollTo(scrollX + deltaX, mScrollView.scrollY)
-        mPrevFirstVisibleFrame = newFrame
-        if (mConfig!!.autoScrollToTopThreshold != null && scrollX <= mConfig!!.autoScrollToTopThreshold!!) {
-          mScrollView.reactSmoothScrollTo(0, mScrollView.scrollY)
-        }
-      }
-    } else {
-      val deltaY: Int = newFrame.top - mPrevFirstVisibleFrame!!.top
-      if (deltaY != 0) {
-        val scrollY: Int = mScrollView.scrollY
-        mScrollView.scrollTo(mScrollView.scrollX, scrollY + deltaY)
-        mPrevFirstVisibleFrame = newFrame
-        if (mConfig!!.autoScrollToTopThreshold != null && scrollY <= mConfig!!.autoScrollToTopThreshold!!) {
-          mScrollView.reactSmoothScrollTo(mScrollView.scrollX, 0)
-        }
-      }
-    }
-  }
-
-  private val contentView: ReactViewGroup
-    get() = mScrollView.getChildAt(0) as ReactViewGroup
-
-  private val uIManagerModule: UIManager
+  private val uiManager: UIManager
     get() = Assertions.assertNotNull(
-      UIManagerHelper.getUIManager(
-        mScrollView.context as ReactContext,
-        ViewUtil.getUIManagerType(mScrollView.id)
-      )
+      UIManagerHelper.getUIManagerForReactTag(mScrollView.context as ReactContext, mScrollView.id)
     )
 
-  private fun computeTargetView() {
-    if (mConfig == null) {
-      return
-    }
-    val contentView: ReactViewGroup? = contentView
-    if (contentView == null) {
-      return
-    }
-    val currentScroll: Int = if (mHorizontal) mScrollView!!.scrollX else mScrollView!!.scrollY
-    for (i in mConfig!!.minIndexForVisible until contentView.childCount) {
-      val child: View = contentView.getChildAt(i)
-      val position: Float = if (mHorizontal) child.x else child.y
-      if (position > currentScroll || i == contentView.childCount - 1) {
-        mFirstVisibleView = WeakReference(child)
-        val frame: Rect = Rect()
-        child.getHitRect(frame)
-        mPrevFirstVisibleFrame = frame
-        break
-      }
-    }
-  }
-
-  // UIManagerListener
-  override fun willDispatchViewUpdates(uiManager: UIManager) {
-    UiThreadUtil.runOnUiThread(
-      object : Runnable {
-        override fun run() {
-          computeTargetView()
-        }
-      })
-  }
-
-  override fun didDispatchMountItems(uiManager: UIManager) {
-    // noop
-  }
-
-  override fun didScheduleMountItems(uiManager: UIManager) {
-    // noop
-  }
-}
-
-/**
- * Manage state for the maintainVisibleContentPosition prop.
- *
- * This uses UIManager to listen to updates and capture position of items before and after layout.
- */
-class MaintainVisibleScrollPositionHelperH(
-  private val mScrollView: ReactHorizontalScrollView,
-  private val mHorizontal: Boolean = false
-): UIManagerListener, MaintainVisibleScrollPositionHelper() {
-  private var mFirstVisibleView: WeakReference<View>? = null
-  private var mPrevFirstVisibleFrame: Rect? = null
-  private var mListening: Boolean = false
-
   /**
    * Start listening to view hierarchy updates. Should be called when this is created.
    */
   override fun start() {
-    if (mListening) {
-      return
-    }
+    if (mListening) return
+
     mListening = true
-    uIManagerModule.addUIManagerEventListener(this)
+    uiManager.addUIManagerEventListener(this)
+    (uiManager as? UIManagerModule)?.uiImplementation?.setLayoutUpdateListener(this)
   }
 
   /**
    * Stop listening to view hierarchy updates. Should be called before this is destroyed.
    */
   override fun stop() {
-    if (!mListening) {
-      return
-    }
+    if (!mListening) return
+
     mListening = false
-    uIManagerModule.removeUIManagerEventListener(this)
+    uiManager.removeUIManagerEventListener(this)
   }
 
   /**
    * Update the scroll position of the managed ScrollView. This should be called after layout
    * has been updated.
    */
   override fun updateScrollPosition() {
-    if ((mConfig == null
-        ) || (mFirstVisibleView == null
-        ) || (mPrevFirstVisibleFrame == null)
-    ) {
+    if ((mConfig == null) || (mFirstVisibleView == null) || (mPrevFirstVisibleFrame == null)) {
       return
     }
+
     val firstVisibleView: View? = mFirstVisibleView!!.get()
-    val newFrame: Rect = Rect()
+    val newFrame = Rect()
     firstVisibleView!!.getHitRect(newFrame)
     if (mHorizontal) {
       val deltaX: Int = newFrame.left - mPrevFirstVisibleFrame!!.left
@@ -239,47 +122,28 @@ class MaintainVisibleScrollPositionHelperH(
     }
   }
 
-  private val contentView: ReactViewGroup
-    get() = mScrollView.getChildAt(0) as ReactViewGroup
-
-  private val uIManagerModule: UIManager
-    get() = Assertions.assertNotNull(
-      UIManagerHelper.getUIManager(
-        mScrollView.context as ReactContext,
-        ViewUtil.getUIManagerType(mScrollView.id)
-      )
-    )
-
   private fun computeTargetView() {
-    if (mConfig == null) {
-      return
-    }
-    val contentView: ReactViewGroup? = contentView
-    if (contentView == null) {
-      return
-    }
-    val currentScroll: Int = if (mHorizontal) mScrollView!!.scrollX else mScrollView!!.scrollY
-    for (i in mConfig!!.minIndexForVisible until contentView.childCount) {
-      val child: View = contentView.getChildAt(i)
-      val position: Float = if (mHorizontal) child.x else child.y
-      if (position > currentScroll || i == contentView.childCount - 1) {
-        mFirstVisibleView = WeakReference(child)
-        val frame: Rect = Rect()
-        child.getHitRect(frame)
-        mPrevFirstVisibleFrame = frame
-        break
+    if (mConfig == null) return
+
+    contentView?.let { contentView ->
+      val currentScroll: Int = if (mHorizontal) mScrollView.scrollX else mScrollView.scrollY
+      for (i in mConfig!!.minIndexForVisible until contentView.childCount) {
+        val child: View = contentView.getChildAt(i)
+        val position: Float = if (mHorizontal) child.x else child.y
+        if (position > currentScroll || i == contentView.childCount - 1) {
+          mFirstVisibleView = WeakReference(child)
+          val frame = Rect()
+          child.getHitRect(frame)
+          mPrevFirstVisibleFrame = frame
+          break
+        }
       }
     }
   }
 
   // UIManagerListener
   override fun willDispatchViewUpdates(uiManager: UIManager) {
-    UiThreadUtil.runOnUiThread(
-      object : Runnable {
-        override fun run() {
-          computeTargetView()
-        }
-      })
+    computeTargetView()
   }
 
   override fun didDispatchMountItems(uiManager: UIManager) {
@@ -289,4 +153,9 @@ class MaintainVisibleScrollPositionHelperH(
   override fun didScheduleMountItems(uiManager: UIManager) {
     // noop
   }
+
+  // LayoutUpdateListener
+  override fun onLayoutUpdated(p0: ReactShadowNode<out ReactShadowNode<*>>?) {
+    updateScrollPosition()
+  }
 }