[BottomSheet] Added back the AccessibilityStateChangedListener implementation in drag handle component

PiperOrigin-RevId: 741553738

Author: hunterstich

lib/java/com/google/android/material/bottomsheet/BottomSheetDragHandleView.java

@@ -35,6 +35,8 @@
 import android.view.ViewGroup.LayoutParams;
 import android.view.ViewParent;
 import android.view.accessibility.AccessibilityEvent;
+import android.view.accessibility.AccessibilityManager;
+import android.view.accessibility.AccessibilityManager.AccessibilityStateChangeListener;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.coordinatorlayout.widget.CoordinatorLayout;
@@ -51,9 +53,12 @@
  * clickable. Clicking the drag handle will toggle the bottom sheet between its collapsed and
  * expanded states.
  */
-public class BottomSheetDragHandleView extends AppCompatImageView {
+public class BottomSheetDragHandleView extends AppCompatImageView implements
+    AccessibilityStateChangeListener {
   private static final int DEF_STYLE_RES = R.style.Widget_Material3_BottomSheet_DragHandle;
 
+  @Nullable private final AccessibilityManager accessibilityManager;
+
   @Nullable private BottomSheetBehavior<?> bottomSheetBehavior;
 
   private final GestureDetector gestureDetector;
@@ -134,6 +139,9 @@ public BottomSheetDragHandleView(
     gestureDetector =
         new GestureDetector(context, gestureListener, new Handler(Looper.getMainLooper()));
 
+    accessibilityManager =
+        (AccessibilityManager) context.getSystemService(Context.ACCESSIBILITY_SERVICE);
+
     ViewCompat.setAccessibilityDelegate(
         this,
         new AccessibilityDelegateCompat() {
@@ -151,10 +159,17 @@ public void onPopulateAccessibilityEvent(View host, @NonNull AccessibilityEvent
   protected void onAttachedToWindow() {
     super.onAttachedToWindow();
     setBottomSheetBehavior(findParentBottomSheetBehavior());
+    if (accessibilityManager != null) {
+      accessibilityManager.addAccessibilityStateChangeListener(this);
+      onAccessibilityStateChanged(accessibilityManager.isEnabled());
+    }
   }
 
   @Override
   protected void onDetachedFromWindow() {
+    if (accessibilityManager != null) {
+      accessibilityManager.removeAccessibilityStateChangeListener(this);
+    }
     setBottomSheetBehavior(null);
     super.onDetachedFromWindow();
   }
@@ -183,6 +198,11 @@ public void setOnClickListener(@Nullable OnClickListener l) {
     super.setOnClickListener(l);
   }
 
+  @Override
+  public void onAccessibilityStateChanged(boolean enabled) {
+    // Do nothing.
+  }
+
   private void setBottomSheetBehavior(@Nullable BottomSheetBehavior<?> behavior) {
     if (bottomSheetBehavior != null) {
       bottomSheetBehavior.removeBottomSheetCallback(bottomSheetCallback);