Accessibility troubleshooting docs for TextField widgets (#103521)

packages/flutter/lib/src/cupertino/text_field.dart

@@ -200,6 +200,8 @@ class CupertinoTextField extends StatefulWidget {
   /// [enableSuggestions], and [enableIMEPersonalizedLearning] properties must
   /// not be null.
   ///
+  /// {@macro flutter.widgets.editableText.accessibility}
+  ///
   /// See also:
   ///
   ///  * [minLines], which is the minimum number of lines to occupy when the

packages/flutter/lib/src/material/text_field.dart

@@ -207,6 +207,8 @@ class _TextFieldSelectionGestureDetectorBuilder extends TextSelectionGestureDete
 ///
 /// {@macro flutter.widgets.editableText.showCaretOnScreen}
 ///
+/// {@macro flutter.widgets.editableText.accessibility}
+///
 /// See also:
 ///
 ///  * [TextFormField], which integrates with the [Form] widget.

packages/flutter/lib/src/widgets/editable_text.dart

@@ -437,6 +437,30 @@ class ToolbarOptions {
 ///  * When the virtual keyboard pops up.
 /// {@endtemplate}
 ///
+/// {@template flutter.widgets.editableText.accessibility}
+/// ## Troubleshooting Common Accessibility Issues
+///
+/// ### Customizing User Input Accessibility Announcements
+///
+/// To customize user input accessibility announcements triggered by text
+/// changes, use [SemanticsService.announce] to make the desired
+/// accessibility announcement.
+///
+/// On iOS, the on-screen keyboard may announce the most recent input
+/// incorrectly when a [TextInputFormatter] inserts a thousands separator to
+/// a currency value text field. The following example demonstrates how to
+/// suppress the default accessibility announcements by always announcing
+/// the content of the text field as a US currency value:
+/// ```dart
+/// onChanged: (String newText) {
+///   if (newText.isNotEmpty) {
+///     SemanticsService.announce('\$' + newText, Directionality.of(context));
+///   }
+/// }
+/// ```
+///
+/// {@endtemplate}
+///
 /// See also:
 ///
 ///  * [TextField], which is a full-featured, material-design text input field