feat: add listener for mount operations on Android

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/bridge/ViewMutationsListener.java

@@ -0,0 +1,20 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+package com.facebook.react.bridge;
+
+import com.facebook.react.fabric.mounting.mountitems.IntBufferMountItem;
+
+import java.util.ArrayList;
+
+public interface ViewMutationsListener {
+    /**
+     * Called right before view mutations are dispatched. This is useful if a
+     * module needs to do something before the views are created/removed.
+     */
+    void willMountViewMutations(ArrayList<IntBufferMountItem> mutations);
+}

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/fabric/mounting/mountitems/InstructionType.java

@@ -0,0 +1,8 @@
+package com.facebook.react.fabric.mounting.mountitems;
+
+import com.facebook.react.fabric.mounting.mountitems.IntBufferMountItem;
+
+public enum InstructionType {
+    CREATE, DELETE, INSERT, REMOVE, UPDATE_PROPS, UPDATE_STATE, UPDATE_LAYOUT, UPDATE_EVENT_EMITTER,
+    UPDATE_PADDING, UPDATE_OVERFLOW_INSET, REMOVE_DELETE_TREE
+}

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/fabric/mounting/mountitems/IntBufferBatchMountItem.java

@@ -20,8 +20,14 @@
 import com.facebook.react.fabric.mounting.MountingManager;
 import com.facebook.react.fabric.mounting.SurfaceMountingManager;
 import com.facebook.react.uimanager.StateWrapper;
+import com.facebook.react.uimanager.UIManagerModule;
 import com.facebook.systrace.Systrace;
 
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.Map;
+import android.view.View;
+
 /**
  * This class represents a batch of {@link MountItem}s, represented directly as int buffers to
  * remove the need for actual MountItem instances.
@@ -117,70 +123,226 @@ public void execute(@NonNull MountingManager mountingManager) {
 
     beginMarkers("mountViews");
 
+    ArrayList<IntBufferMountItem> mutationsArray = new ArrayList<>();
+
+    // we put views in the mount item objects also for some operations since tags
+    // are only mapped to ViewState which are internal.
+    // In most cases we will need the view to perform an action in the listener
     int i = 0, j = 0;
     while (i < mIntBufferLen) {
       int rawType = mIntBuffer[i++];
       int type = rawType & ~INSTRUCTION_FLAG_MULTIPLE;
       int numInstructions = ((rawType & INSTRUCTION_FLAG_MULTIPLE) != 0 ? mIntBuffer[i++] : 1);
       for (int k = 0; k < numInstructions; k++) {
+        IntBufferMountItem item;
         if (type == INSTRUCTION_CREATE) {
           String componentName = getFabricComponentName((String) mObjBuffer[j++]);
-          surfaceMountingManager.createView(
-              componentName,
-              mIntBuffer[i++],
-              mObjBuffer[j++],
-              castToState(mObjBuffer[j++]),
-              castToEventEmitter(mObjBuffer[j++]),
-              mIntBuffer[i++] == 1);
+          int reactTag = mIntBuffer[i++];
+          View view = null;
+          if (surfaceMountingManager.getViewExists(reactTag)) {
+            view = surfaceMountingManager.getView(reactTag);
+          }
+          Object props = mObjBuffer[j++];
+          StateWrapper stateWrapper = castToState(mObjBuffer[j++]);
+          EventEmitterWrapper eventEmitterWrapper = castToEventEmitter(mObjBuffer[j++]);
+          boolean isLayoutable = mIntBuffer[i++] == 1;
+          item = new IntBufferMountItemCreate(reactTag,
+                  view, componentName, props, stateWrapper, eventEmitterWrapper, isLayoutable);
+
         } else if (type == INSTRUCTION_DELETE) {
-          surfaceMountingManager.deleteView(mIntBuffer[i++]);
+          int reactTag = mIntBuffer[i++];
+          item = new IntBufferMountItemDelete(reactTag, null);
         } else if (type == INSTRUCTION_INSERT) {
           int tag = mIntBuffer[i++];
+          View view = null;
+          if (surfaceMountingManager.getViewExists(tag)) {
+            view = surfaceMountingManager.getView(tag);
+          }
           int parentTag = mIntBuffer[i++];
-          surfaceMountingManager.addViewAt(parentTag, tag, mIntBuffer[i++]);
+          View parentView = null;
+          if (surfaceMountingManager.getViewExists(parentTag)) {
+            parentView = surfaceMountingManager.getView(parentTag);
+          }
+          int index = mIntBuffer[i++];
+          item = new IntBufferMountItemInsert(tag, view, parentTag, parentView, index);
         } else if (type == INSTRUCTION_REMOVE) {
-          surfaceMountingManager.removeViewAt(mIntBuffer[i++], mIntBuffer[i++], mIntBuffer[i++]);
+          int tag = mIntBuffer[i++];
+          View view = null;
+          if (surfaceMountingManager.getViewExists(tag)) {
+            view = surfaceMountingManager.getView(tag);
+          }
+          int parentTag = mIntBuffer[i++];
+          View parentView = null;
+          if (surfaceMountingManager.getViewExists(parentTag)) {
+            parentView = surfaceMountingManager.getView(parentTag);
+          }
+          int index = mIntBuffer[i++];
+          item = new IntBufferMountItemRemove(tag, view, parentTag, parentView, index);
         } else if (type == INSTRUCTION_REMOVE_DELETE_TREE) {
-          surfaceMountingManager.removeDeleteTreeAt(
-              mIntBuffer[i++], mIntBuffer[i++], mIntBuffer[i++]);
+          int tag = mIntBuffer[i++];
+          View view = null;
+          if (surfaceMountingManager.getViewExists(tag)) {
+            view = surfaceMountingManager.getView(tag);
+          }
+          int parentTag = mIntBuffer[i++];
+          View parentView = null;
+          if (surfaceMountingManager.getViewExists(parentTag)) {
+            parentView = surfaceMountingManager.getView(parentTag);
+          }
+          int index = mIntBuffer[i++];
+          item = new IntBufferMountItemRemoveDeleteTree(tag, view, parentTag, parentView, index);
         } else if (type == INSTRUCTION_UPDATE_PROPS) {
-          surfaceMountingManager.updateProps(mIntBuffer[i++], mObjBuffer[j++]);
+          int reactTag = mIntBuffer[i++];
+          View view = null;
+          if (surfaceMountingManager.getViewExists(reactTag)) {
+            view = surfaceMountingManager.getView(reactTag);
+          }
+          Object props = mObjBuffer[j++];
+          item = new IntBufferMountItemUpdateProps(reactTag, view, props);
         } else if (type == INSTRUCTION_UPDATE_STATE) {
-          surfaceMountingManager.updateState(mIntBuffer[i++], castToState(mObjBuffer[j++]));
+          int reactTag = mIntBuffer[i++];
+          View view = null;
+          if (surfaceMountingManager.getViewExists(reactTag)) {
+            view = surfaceMountingManager.getView(reactTag);
+          }
+          StateWrapper stateWrapper = castToState(mObjBuffer[j++]);
+          item = new IntBufferMountItemUpdateState(reactTag, view, stateWrapper);
         } else if (type == INSTRUCTION_UPDATE_LAYOUT) {
           int reactTag = mIntBuffer[i++];
+          View view = null;
+          if (surfaceMountingManager.getViewExists(reactTag)) {
+            view = surfaceMountingManager.getView(reactTag);
+          }
           int parentTag = mIntBuffer[i++];
+          View parentView = null;
+          if (surfaceMountingManager.getViewExists(parentTag)) {
+            parentView = surfaceMountingManager.getView(parentTag);
+          }
           int x = mIntBuffer[i++];
           int y = mIntBuffer[i++];
           int width = mIntBuffer[i++];
           int height = mIntBuffer[i++];
           int displayType = mIntBuffer[i++];
-
-          surfaceMountingManager.updateLayout(
-              reactTag, parentTag, x, y, width, height, displayType);
-
+          item = new IntBufferMountItemUpdateLayout(reactTag, view, parentTag, parentView, x, y,
+                  width, height, displayType);
         } else if (type == INSTRUCTION_UPDATE_PADDING) {
-          surfaceMountingManager.updatePadding(
-              mIntBuffer[i++], mIntBuffer[i++], mIntBuffer[i++], mIntBuffer[i++], mIntBuffer[i++]);
+          int reactTag = mIntBuffer[i++];
+          View view = null;
+          if (surfaceMountingManager.getViewExists(reactTag)) {
+            view = surfaceMountingManager.getView(reactTag);
+          }
+          int left = mIntBuffer[i++];
+          int top = mIntBuffer[i++];
+          int right = mIntBuffer[i++];
+          int bottom = mIntBuffer[i++];
+          item = new IntBufferMountItemUpdatePadding(reactTag, view, left, top, right, bottom);
         } else if (type == INSTRUCTION_UPDATE_OVERFLOW_INSET) {
           int reactTag = mIntBuffer[i++];
+          View view = null;
+          if (surfaceMountingManager.getViewExists(reactTag)) {
+            view = surfaceMountingManager.getView(reactTag);
+          }
           int overflowInsetLeft = mIntBuffer[i++];
           int overflowInsetTop = mIntBuffer[i++];
           int overflowInsetRight = mIntBuffer[i++];
           int overflowInsetBottom = mIntBuffer[i++];
-
-          surfaceMountingManager.updateOverflowInset(
-              reactTag,
-              overflowInsetLeft,
-              overflowInsetTop,
-              overflowInsetRight,
-              overflowInsetBottom);
+          item = new IntBufferMountItemUpdateOverflowInset(reactTag, view, overflowInsetLeft,
+                  overflowInsetTop, overflowInsetRight, overflowInsetBottom);
         } else if (type == INSTRUCTION_UPDATE_EVENT_EMITTER) {
-          surfaceMountingManager.updateEventEmitter(
-              mIntBuffer[i++], castToEventEmitter(mObjBuffer[j++]));
+          int reactTag = mIntBuffer[i++];
+          EventEmitterWrapper eventEmitterWrapper = castToEventEmitter(mObjBuffer[j++]);
+          item = new IntBufferMountItemUpdateEventEmitter(reactTag, null, eventEmitterWrapper);
         } else {
           throw new IllegalArgumentException(
-              "Invalid type argument to IntBufferBatchMountItem: " + type + " at index: " + i);
+                  "Invalid type argument to IntBufferBatchMountItem: " + type + " at index: " + i);
+        }
+        mutationsArray.add(item);
+      }
+    }
+
+    surfaceMountingManager.getContext().getNativeModule(UIManagerModule.class).viewMutationsWillMount(mutationsArray);
+
+    for (IntBufferMountItem elem: mutationsArray) {
+      switch (elem.getInstructionType()) {
+        case CREATE: {
+          IntBufferMountItemCreate createElem = (IntBufferMountItemCreate) elem;
+          surfaceMountingManager.createView(
+                  createElem.getComponentName(),
+                  createElem.getReactTag(),
+                  createElem.getProps(),
+                  createElem.getStateWrapper(),
+                  createElem.getEventEmitterWrapper(),
+                  createElem.isLayoutable());
+          break;
+        }
+        case DELETE: {
+          IntBufferMountItemDelete deleteElem = (IntBufferMountItemDelete) elem;
+          surfaceMountingManager.deleteView(deleteElem.getReactTag());
+          break;
+        }
+        case INSERT: {
+          IntBufferMountItemInsert insertElem = (IntBufferMountItemInsert) elem;
+          surfaceMountingManager.addViewAt(insertElem.getParentTag(), insertElem.getReactTag(), insertElem.getIndex());
+          break;
+        }
+        case REMOVE: {
+          IntBufferMountItemRemove removeElem = (IntBufferMountItemRemove) elem;
+          surfaceMountingManager.removeViewAt(removeElem.getReactTag(), removeElem.getParentTag(), removeElem.getIndex());
+          break;
+        }
+        case REMOVE_DELETE_TREE: {
+          IntBufferMountItemRemoveDeleteTree removeDeleteTreeElem = (IntBufferMountItemRemoveDeleteTree) elem;
+          surfaceMountingManager.removeDeleteTreeAt(removeDeleteTreeElem.getReactTag(),
+                  removeDeleteTreeElem.getParentTag(), removeDeleteTreeElem.getIndex());
+          break;
+        }
+        case UPDATE_PROPS: {
+          IntBufferMountItemUpdateProps updatePropsElem = (IntBufferMountItemUpdateProps) elem;
+          surfaceMountingManager.updateProps(updatePropsElem.getReactTag(),
+                  updatePropsElem.getProps());
+          break;
+        }
+        case UPDATE_STATE: {
+          IntBufferMountItemUpdateState updateStateElem = (IntBufferMountItemUpdateState) elem;
+          surfaceMountingManager.updateState(updateStateElem.getReactTag(),
+                  updateStateElem.getStateWrapper());
+          break;
+        }
+        case UPDATE_LAYOUT: {
+          IntBufferMountItemUpdateLayout updateLayoutElem = (IntBufferMountItemUpdateLayout) elem;
+          surfaceMountingManager.updateLayout(updateLayoutElem.getReactTag(),
+                  updateLayoutElem.getParentTag(), updateLayoutElem.getX(), updateLayoutElem.getY(),
+                  updateLayoutElem.getWidth(), updateLayoutElem.getHeight(),
+                  updateLayoutElem.getDisplayType());
+          break;
+        }
+        case UPDATE_PADDING: {
+          IntBufferMountItemUpdatePadding updatePaddingElem = (IntBufferMountItemUpdatePadding) elem;
+          surfaceMountingManager.updatePadding(updatePaddingElem.getReactTag(),
+                  updatePaddingElem.getLeft(), updatePaddingElem.getTop(),
+                  updatePaddingElem.getRight(), updatePaddingElem.getBottom());
+          break;
+        }
+        case UPDATE_OVERFLOW_INSET: {
+          IntBufferMountItemUpdateOverflowInset updateOverflowInsetElem =
+                  (IntBufferMountItemUpdateOverflowInset) elem;
+          surfaceMountingManager.updateOverflowInset(updateOverflowInsetElem.getReactTag(),
+                  updateOverflowInsetElem.getOverflowInsetLeft(),
+                  updateOverflowInsetElem.getOverflowInsetTop(),
+                  updateOverflowInsetElem.getOverflowInsetRight(),
+                  updateOverflowInsetElem.getOverflowInsetBottom());
+          break;
+        }
+        case UPDATE_EVENT_EMITTER: {
+          IntBufferMountItemUpdateEventEmitter updateEventEmitterElem =
+                  (IntBufferMountItemUpdateEventEmitter) elem;
+          surfaceMountingManager.updateEventEmitter(updateEventEmitterElem.getReactTag(),
+                  updateEventEmitterElem.getEventEmitterWrapper());
+          break;
+        }
+        default: {
+          throw new IllegalArgumentException(
+                  "Invalid type argument to IntBufferBatchMountItem: " + elem.getInstructionType());
         }
       }
     }

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/fabric/mounting/mountitems/IntBufferMountItem.java

@@ -0,0 +1,30 @@
+package com.facebook.react.fabric.mounting.mountitems;
+
+import com.facebook.react.fabric.mounting.mountitems.IntBufferMountItem;
+import com.facebook.react.fabric.mounting.mountitems.InstructionType;
+
+import android.view.View;
+
+public abstract class IntBufferMountItem {
+    private final InstructionType instructionType;
+    private final int reactTag;
+    private final View view;
+
+    public IntBufferMountItem(InstructionType instructionType, int reactTag, View view) {
+        this.instructionType = instructionType;
+        this.reactTag = reactTag;
+        this.view = view;
+    }
+
+    public InstructionType getInstructionType() {
+        return instructionType;
+    }
+
+    public int getReactTag() {
+        return reactTag;
+    }
+
+    public View getView() {
+        return view;
+    }
+}

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/fabric/mounting/mountitems/IntBufferMountItemCreate.java

@@ -0,0 +1,46 @@
+package com.facebook.react.fabric.mounting.mountitems;
+
+import com.facebook.react.fabric.mounting.mountitems.InstructionType;
+import com.facebook.react.fabric.mounting.mountitems.IntBufferMountItem;
+import com.facebook.react.uimanager.StateWrapper;
+import com.facebook.react.fabric.events.EventEmitterWrapper;
+
+import android.view.View;
+
+public class IntBufferMountItemCreate extends IntBufferMountItem {
+
+    private final String componentName;
+    private final Object props;
+    private final StateWrapper stateWrapper;
+    private final EventEmitterWrapper eventEmitterWrapper;
+    private final boolean isLayoutable;
+
+    public IntBufferMountItemCreate(int reactTag, View view, String componentName, Object props, StateWrapper stateWrapper, EventEmitterWrapper eventEmitterWrapper, boolean isLayoutable) {
+        super(InstructionType.CREATE, reactTag, view);
+        this.componentName = componentName;
+        this.props = props;
+        this.stateWrapper = stateWrapper;
+        this.eventEmitterWrapper = eventEmitterWrapper;
+        this.isLayoutable = isLayoutable;
+    }
+
+    public String getComponentName() {
+        return componentName;
+    }
+
+    public Object getProps() {
+        return props;
+    }
+
+    public StateWrapper getStateWrapper() {
+        return stateWrapper;
+    }
+
+    public EventEmitterWrapper getEventEmitterWrapper() {
+        return eventEmitterWrapper;
+    }
+
+    public boolean isLayoutable() {
+        return isLayoutable;
+    }
+}

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/fabric/mounting/mountitems/IntBufferMountItemDelete.java

@@ -0,0 +1,13 @@
+package com.facebook.react.fabric.mounting.mountitems;
+
+import com.facebook.react.fabric.mounting.mountitems.IntBufferMountItem;
+import com.facebook.react.fabric.mounting.mountitems.InstructionType;
+
+import android.view.View;
+
+public class IntBufferMountItemDelete extends IntBufferMountItem {
+
+    public IntBufferMountItemDelete(int reactTag, View view) {
+        super(InstructionType.DELETE, reactTag, view);
+    }
+}