[CleanUp][TextField] Centralize accessibility event dispatching logic for drop-downs

This also fixes the bug that clients cannot use custom AccessibilityDelegate with drop-down mode.

PiperOrigin-RevId: 447748501

Author: drchen

lib/java/com/google/android/material/textfield/DropdownMenuEndIconDelegate.java

@@ -47,7 +47,6 @@
 import androidx.core.view.ViewCompat;
 import androidx.core.view.accessibility.AccessibilityNodeInfoCompat;
 import com.google.android.material.animation.AnimationUtils;
-import com.google.android.material.textfield.TextInputLayout.AccessibilityDelegate;
 import com.google.android.material.textfield.TextInputLayout.BoxBackgroundMode;
 
 /** Default initialization of the exposed dropdown menu {@link TextInputLayout.EndIconMode}. */
@@ -62,37 +61,6 @@ class DropdownMenuEndIconDelegate extends EndIconDelegate {
   @Nullable
   private AutoCompleteTextView autoCompleteTextView;
 
-  private final TextInputLayout.AccessibilityDelegate accessibilityDelegate =
-      new AccessibilityDelegate(textInputLayout) {
-        @Override
-        public void onInitializeAccessibilityNodeInfo(
-            View host, @NonNull AccessibilityNodeInfoCompat info) {
-          super.onInitializeAccessibilityNodeInfo(host, info);
-          // The non-editable exposed dropdown menu behaves like a Spinner.
-          if (!isEditable(autoCompleteTextView)) {
-            info.setClassName(Spinner.class.getName());
-          }
-          if (info.isShowingHintText()) {
-            // Set hint text to null so TalkBack doesn't announce the label twice when there is no
-            // item selected.
-            info.setHintText(null);
-          }
-        }
-
-        @Override
-        public void onPopulateAccessibilityEvent(View host, @NonNull AccessibilityEvent event) {
-          super.onPopulateAccessibilityEvent(host, event);
-          // If dropdown is non editable, layout click is what triggers showing/hiding the popup
-          // list. Otherwise, arrow icon alone is what triggers it.
-          if (event.getEventType() == TYPE_VIEW_CLICKED
-              && accessibilityManager.isEnabled()
-              && !isEditable(autoCompleteTextView)) {
-            showHideDropdown();
-            updateDropdownPopupDirty();
-          }
-        }
-      };
-
   private final OnClickListener onIconClickListener = view -> showHideDropdown();
 
   private final OnFocusChangeListener onEditTextFocusChangeListener = (view, hasFocus) -> {
@@ -177,8 +145,6 @@ public void onEditTextAttached(@Nullable EditText editText) {
     if (!isEditable(editText) && accessibilityManager.isTouchExplorationEnabled()) {
       ViewCompat.setImportantForAccessibility(endIconView, IMPORTANT_FOR_ACCESSIBILITY_NO);
     }
-    textInputLayout.setTextInputAccessibilityDelegate(accessibilityDelegate);
-
     textInputLayout.setEndIconVisible(true);
   }
 
@@ -202,6 +168,32 @@ OnFocusChangeListener getOnEditTextFocusChangeListener() {
     return onEditTextFocusChangeListener;
   }
 
+  @Override
+  public void onInitializeAccessibilityNodeInfo(
+      View host, @NonNull AccessibilityNodeInfoCompat info) {
+    // The non-editable exposed dropdown menu behaves like a Spinner.
+    if (!isEditable(autoCompleteTextView)) {
+      info.setClassName(Spinner.class.getName());
+    }
+    if (info.isShowingHintText()) {
+      // Set hint text to null so TalkBack doesn't announce the label twice when there is no
+      // item selected.
+      info.setHintText(null);
+    }
+  }
+
+  @Override
+  public void onPopulateAccessibilityEvent(View host, @NonNull AccessibilityEvent event) {
+    // If dropdown is non editable, layout click is what triggers showing/hiding the popup
+    // list. Otherwise, arrow icon alone is what triggers it.
+    if (event.getEventType() == TYPE_VIEW_CLICKED
+        && accessibilityManager.isEnabled()
+        && !isEditable(autoCompleteTextView)) {
+      showHideDropdown();
+      updateDropdownPopupDirty();
+    }
+  }
+
   private void showHideDropdown() {
     if (autoCompleteTextView == null) {
       return;

lib/java/com/google/android/material/textfield/EndIconDelegate.java

@@ -18,12 +18,15 @@
 
 import android.content.Context;
 import android.text.Editable;
+import android.view.View;
 import android.view.View.OnClickListener;
 import android.view.View.OnFocusChangeListener;
+import android.view.accessibility.AccessibilityEvent;
 import android.widget.EditText;
 import androidx.annotation.DrawableRes;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
+import androidx.core.view.accessibility.AccessibilityNodeInfoCompat;
 import com.google.android.material.internal.CheckableImageButton;
 import com.google.android.material.textfield.TextInputLayout.BoxBackgroundMode;
 
@@ -122,4 +125,17 @@ void beforeEditTextChanged(CharSequence s, int start, int count, int after) {}
    * @see android.text.TextWatcher#afterTextChanged(Editable)
    */
   void afterEditTextChanged(Editable s) {}
+
+  /**
+   * This method will be called when the associated {@link TextInputLayout} is initializing the
+   * accessibility node info.
+   */
+  void onInitializeAccessibilityNodeInfo(View host, @NonNull AccessibilityNodeInfoCompat info) {}
+
+  /**
+   * This method will be called when the associated {@link TextInputLayout} is populating a
+   * accessibility event.
+   */
+  void onPopulateAccessibilityEvent(View host, @NonNull AccessibilityEvent event) {}
 }
+

lib/java/com/google/android/material/textfield/TextInputLayout.java

@@ -4239,6 +4239,15 @@ public void onInitializeAccessibilityNodeInfo(
           info.setLabelFor(helperTextView);
         }
       }
+
+      layout.endLayout.getEndIconDelegate().onInitializeAccessibilityNodeInfo(host, info);
+    }
+
+    @Override
+    public void onPopulateAccessibilityEvent(
+        @NonNull View host, @NonNull AccessibilityEvent event) {
+      super.onPopulateAccessibilityEvent(host, event);
+      layout.endLayout.getEndIconDelegate().onPopulateAccessibilityEvent(host, event);
     }
   }
 }