src/Tizen.NUI/src/public/BaseComponents/ViewAccessibility.cs

   1 /*
   2  * Copyright(c) 2021 Samsung Electronics Co., Ltd.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  * http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  *
  16  */
  17
  18 using System;
  19 using System.Collections.Generic;
  20 using System.ComponentModel;
  21 using System.Runtime.InteropServices;
  22 using Tizen.NUI;
  23
  24 namespace Tizen.NUI.BaseComponents
  25 {
  26     /// <summary>
  27     /// AccessibilityRange is used to store data related with Text.
  28     /// </summary>
  29     [EditorBrowsable(EditorBrowsableState.Never)]
  30     public class AccessibilityRange
  31     {
  32         /// <summary>
  33         /// Start position in stored text.
  34         /// </summary>
  35         public int StartOffset { get; set; } = 0;
  36
  37         /// <summary>
  38         /// End position in stored text.
  39         /// </summary>
  40         public int EndOffset { get; set; } = 0;
  41
  42         /// <summary>
  43         /// Text content in stored text.
  44         /// </summary>
  45         public string Content { get; set; } = "";
  46     }
  47
  48     /// <summary>
  49     /// View is the base class for all views.
  50     /// </summary>
  51     /// <since_tizen> 3 </since_tizen>
  52     public partial class View
  53     {
  54         ///////////////////////////////////////////////////////////////////
  55         // ****************** Accessibility Attributes ****************** //
  56         ///////////////////////////////////////////////////////////////////
  57
  58         /// <summary>
  59         /// Dictionary of accessibility attributes (key-value pairs of strings).
  60         /// </summary>
  61         [EditorBrowsable(EditorBrowsableState.Never)]
  62         protected Dictionary<string, string> AccessibilityAttributes { get; } = new Dictionary<string, string>();
  63
  64         ///////////////////////////////////////////////////////////////////
  65         // ************************** Highlight ************************ //
  66         ///////////////////////////////////////////////////////////////////
  67
  68         /// <summary>
  69         /// Clears accessibility highlight.
  70         /// </summary>
  71         /// <returns>True if cleared, otherwise false when it is not possible</returns>
  72         [EditorBrowsable(EditorBrowsableState.Never)]
  73         public bool ClearAccessibilityHighlight()
  74         {
  75             bool result = Interop.ControlDevel.DaliToolkitDevelControlClearAccessibilityHighlight(SwigCPtr);
  76             if (NDalicPINVOKE.SWIGPendingException.Pending) throw NDalicPINVOKE.SWIGPendingException.Retrieve();
  77             return result;
  78         }
  79
  80         /// <summary>
  81         /// Grabs accessibility highlight.
  82         /// </summary>
  83         /// <returns>True if cleared, otherwise false when it is not possible</returns>
  84         [EditorBrowsable(EditorBrowsableState.Never)]
  85         public bool GrabAccessibilityHighlight()
  86         {
  87             bool result = Interop.ControlDevel.DaliToolkitDevelControlGrabAccessibilityHighlight(SwigCPtr);
  88             if (NDalicPINVOKE.SWIGPendingException.Pending) throw NDalicPINVOKE.SWIGPendingException.Retrieve();
  89             return result;
  90         }
  91
  92         /// <summary>
  93         /// Flag to check whether this view is highlighted or not.
  94         /// </summary>
  95         [EditorBrowsable(EditorBrowsableState.Never)]
  96         protected bool IsHighlighted
  97         {
  98             get
  99             {
 100                 return (this == Accessibility.Accessibility.GetCurrentlyHighlightedView());
 101             }
 102         }
 103
 104         ///////////////////////////////////////////////////////////////////
 105         // ****************** Accessibility Relations ******************* //
 106         ///////////////////////////////////////////////////////////////////
 107
 108         /// <summary>
 109         /// Creates relation between objects.
 110         /// </summary>
 111         /// <param name="second">Object which will be in relation.</param>
 112         /// <param name="relation">Relation type.</param>
 113         /// <exception cref="ArgumentNullException">You must pass valid object. NULL could not be in relation.</exception>
 114         [EditorBrowsable(EditorBrowsableState.Never)]
 115         public void AppendAccessibilityRelation(View second, AccessibilityRelationType relation)
 116         {
 117             if (second is null)
 118             {
 119                 throw new ArgumentNullException(nameof(second));
 120             }
 121
 122             Interop.ControlDevel.DaliToolkitDevelControlAppendAccessibilityRelation(SwigCPtr, second.SwigCPtr, (int)relation);
 123             if (NDalicPINVOKE.SWIGPendingException.Pending) throw NDalicPINVOKE.SWIGPendingException.Retrieve();
 124         }
 125
 126         /// <summary>
 127         /// Removes accessibility relation.
 128         /// </summary>
 129         /// <param name="second">Object which will be removed in relation</param>
 130         /// <param name="relation">Relation type</param>
 131         [EditorBrowsable(EditorBrowsableState.Never)]
 132         public void RemoveAccessibilityRelation(View second, AccessibilityRelationType relation)
 133         {
 134             if (second is null)
 135             {
 136                 throw new ArgumentNullException(nameof(second));
 137             }
 138
 139             Interop.ControlDevel.DaliToolkitDevelControlRemoveAccessibilityRelation(SwigCPtr, second.SwigCPtr, (int)relation);
 140             if (NDalicPINVOKE.SWIGPendingException.Pending) throw NDalicPINVOKE.SWIGPendingException.Retrieve();
 141         }
 142
 143         /// <summary>
 144         /// Removes all previously appended relations.
 145         /// </summary>
 146         [EditorBrowsable(EditorBrowsableState.Never)]
 147         public void ClearAccessibilityRelations()
 148         {
 149             Interop.ControlDevel.DaliToolkitDevelControlClearAccessibilityRelations(SwigCPtr);
 150             if (NDalicPINVOKE.SWIGPendingException.Pending) throw NDalicPINVOKE.SWIGPendingException.Retrieve();
 151         }
 152
 153         /// <summary>
 154         /// Gets accessibility collection connected with the current object.
 155         /// </summary>
 156         /// <returns>A dictionary mapping a relation type to a set of objects in that relation</returns>
 157         [EditorBrowsable(EditorBrowsableState.Never)]
 158         public Dictionary<AccessibilityRelationType, List<View>> GetAccessibilityRelations()
 159         {
 160             var list = new List<KeyValuePair<int, IntPtr>>();
 161             var listHandle = GCHandle.Alloc(list);
 162             var callback = new Interop.ControlDevel.GetAccessibilityRelationsCallback(GetAccessibilityRelationsCallback);
 163
 164             Interop.ControlDevel.DaliToolkitDevelControlGetAccessibilityRelations(SwigCPtr, callback, GCHandle.ToIntPtr(listHandle));
 165             listHandle.Free();
 166             if (NDalicPINVOKE.SWIGPendingException.Pending) throw NDalicPINVOKE.SWIGPendingException.Retrieve();
 167
 168             var result = new Dictionary<AccessibilityRelationType, List<View>>();
 169
 170             foreach (var pair in list)
 171             {
 172                 var key = (AccessibilityRelationType)pair.Key;
 173                 var value = this.GetInstanceSafely<View>(pair.Value);
 174
 175                 if (!result.ContainsKey(key))
 176                 {
 177                     result[key] = new List<View>();
 178                 }
 179
 180                 result[key].Add(value);
 181             }
 182
 183             return result;
 184         }
 185
 186         private static void GetAccessibilityRelationsCallback(int relationType, IntPtr relationTarget, IntPtr userData)
 187         {
 188             var handle = GCHandle.FromIntPtr(userData);
 189             var list = (List<KeyValuePair<int, IntPtr>>)handle.Target;
 190
 191             list.Add(new KeyValuePair<int, IntPtr>(relationType, relationTarget));
 192         }
 193
 194         ///////////////////////////////////////////////////////////////////
 195         // ********************* ReadingInfoType *********************** //
 196         ///////////////////////////////////////////////////////////////////
 197
 198         /// <summary>
 199         /// Sets accessibility reading information.
 200         /// </summary>
 201         /// <param name="type">Reading information type</param>
 202         [EditorBrowsable(EditorBrowsableState.Never)]
 203         public void SetAccessibilityReadingInfoTypes(AccessibilityReadingInfoTypes type)
 204         {
 205             Interop.ControlDevel.DaliToolkitDevelControlSetAccessibilityReadingInfoTypes(SwigCPtr, (int)type);
 206             if (NDalicPINVOKE.SWIGPendingException.Pending) throw NDalicPINVOKE.SWIGPendingException.Retrieve();
 207         }
 208
 209         /// <summary>
 210         /// Gets accessibility reading information.
 211         /// </summary>
 212         /// <returns>Reading information type</returns>
 213         [EditorBrowsable(EditorBrowsableState.Never)]
 214         public AccessibilityReadingInfoTypes GetAccessibilityReadingInfoTypes()
 215         {
 216             AccessibilityReadingInfoTypes result = (AccessibilityReadingInfoTypes)Interop.ControlDevel.DaliToolkitDevelControlGetAccessibilityReadingInfoTypes(SwigCPtr);
 217             if (NDalicPINVOKE.SWIGPendingException.Pending) throw NDalicPINVOKE.SWIGPendingException.Retrieve();
 218             return result;
 219         }
 220
 221         ///////////////////////////////////////////////////////////////////
 222         // ******************** Accessibility States ******************* //
 223         ///////////////////////////////////////////////////////////////////
 224
 225         /// <summary>
 226         /// Notifies sending notifications about the current states to accessibility clients.
 227         /// </summary>
 228         /// <remarks>
 229         /// In essence, this is equivalent to calling EmitAccessibilityStateChangedEvent in a loop for all specified states.
 230         /// If recursive mode is specified, all children of the Accessibility object will also re-emit the states.
 231         /// </remarks>
 232         /// <param name="states">Accessibility States</param>
 233         /// <param name="notifyMode">Controls the notification strategy</param>
 234         [EditorBrowsable(EditorBrowsableState.Never)]
 235         public void NotifyAccessibilityStatesChange(AccessibilityStates states, AccessibilityStatesNotifyMode notifyMode)
 236         {
 237             if (states is null)
 238             {
 239                 throw new ArgumentNullException(nameof(states));
 240             }
 241
 242             Interop.ControlDevel.DaliToolkitDevelControlNotifyAccessibilityStateChange(SwigCPtr, states.BitMask, (int)notifyMode);
 243             if (NDalicPINVOKE.SWIGPendingException.Pending) throw NDalicPINVOKE.SWIGPendingException.Retrieve();
 244         }
 245
 246         /// <summary>
 247         /// Gets Accessibility States.
 248         /// </summary>
 249         /// <returns>Accessibility States</returns>
 250         [EditorBrowsable(EditorBrowsableState.Never)]
 251         public AccessibilityStates GetAccessibilityStates()
 252         {
 253             var result = new AccessibilityStates {BitMask = Interop.ControlDevel.DaliToolkitDevelControlGetAccessibilityStates(SwigCPtr)};
 254             if (NDalicPINVOKE.SWIGPendingException.Pending) throw NDalicPINVOKE.SWIGPendingException.Retrieve();
 255             return result;
 256         }
 257
 258         ///////////////////////////////////////////////////////////////////
 259         // ************************ Accessible ************************* //
 260         ///////////////////////////////////////////////////////////////////
 261
 262         /// <summary>
 263         /// Emits accessibility property changed event.
 264         /// </summary>
 265         /// <param name="changeEvent">Property changed event</param>
 266         [EditorBrowsable(EditorBrowsableState.Never)]
 267         public void EmitAccessibilityEvent(AccessibilityPropertyChangeEvent changeEvent)
 268         {
 269             Interop.ControlDevel.DaliAccessibilityEmitAccessibilityEvent(SwigCPtr, Convert.ToInt32(changeEvent));
 270             if (NDalicPINVOKE.SWIGPendingException.Pending) throw NDalicPINVOKE.SWIGPendingException.Retrieve();
 271         }
 272
 273         /// <summary>
 274         /// Emits accessibility states changed event.
 275         /// </summary>
 276         /// <param name="state">Accessibility state</param>
 277         /// <param name="equal">True if the state is set or enabled, otherwise false</param>
 278         [EditorBrowsable(EditorBrowsableState.Never)]
 279         public void EmitAccessibilityStateChangedEvent(AccessibilityState state, bool equal)
 280         {
 281             Interop.ControlDevel.DaliAccessibilityEmitAccessibilityStateChangedEvent(SwigCPtr, (int)state, Convert.ToInt32(equal));
 282             if (NDalicPINVOKE.SWIGPendingException.Pending) throw NDalicPINVOKE.SWIGPendingException.Retrieve();
 283         }
 284
 285         /// <summary>
 286         /// Emits accessibility text inserted event.
 287         /// </summary>
 288         /// <param name="cursorPosition">Text cursor position</param>
 289         /// <param name="length">Text length</param>
 290         /// <param name="content">Inserted text content</param>
 291         [EditorBrowsable(EditorBrowsableState.Never)]
 292         public void EmitTextInsertedEvent(int cursorPosition, int length, string content)
 293         {
 294             Interop.ControlDevel.DaliAccessibilityEmitTextInsertedEvent(SwigCPtr, cursorPosition, length, content);
 295             if (NDalicPINVOKE.SWIGPendingException.Pending) throw NDalicPINVOKE.SWIGPendingException.Retrieve();
 296         }
 297
 298         /// <summary>
 299         /// Emits accessibility text deleted event.
 300         /// </summary>
 301         /// <param name="cursorPosition">Text cursor position</param>
 302         /// <param name="length">Text length</param>
 303         /// <param name="content">Inserted text content</param>
 304         [EditorBrowsable(EditorBrowsableState.Never)]
 305         public void EmitTextDeletedEvent(int cursorPosition, int length, string content)
 306         {
 307             Interop.ControlDevel.DaliAccessibilityEmitTextDeletedEvent(SwigCPtr, cursorPosition, length, content);
 308             if (NDalicPINVOKE.SWIGPendingException.Pending) throw NDalicPINVOKE.SWIGPendingException.Retrieve();
 309         }
 310
 311         /// <summary>
 312         /// Emits accessibility text cursor moved event.
 313         /// </summary>
 314         /// <param name="cursorPosition">The new cursor position</param>
 315         [EditorBrowsable(EditorBrowsableState.Never)]
 316         public void EmitTextCursorMovedEvent(int cursorPosition)
 317         {
 318             Interop.ControlDevel.DaliAccessibilityEmitTextCursorMovedEvent(SwigCPtr, cursorPosition);
 319             if (NDalicPINVOKE.SWIGPendingException.Pending) throw NDalicPINVOKE.SWIGPendingException.Retrieve();
 320         }
 321
 322         /// <summary>
 323         /// Modifiable collection of suppressed AT-SPI events (D-Bus signals).
 324         /// </summary>
 325         [EditorBrowsable(EditorBrowsableState.Never)]
 326         public AccessibilityEvents AccessibilitySuppressedEvents
 327         {
 328             get
 329             {
 330                 return new AccessibilityEvents {Owner = this};
 331             }
 332         }
 333
 334         ///////////////////////////////////////////////////////////////////
 335         // ************************** Bridge *************************** //
 336         ///////////////////////////////////////////////////////////////////
 337
 338         /// <summary>
 339         /// Registers component as a source of an accessibility "default label".
 340         /// The "Default label" is a text that could be read by screen-reader immediately
 341         /// after the navigation context has changed (window activates, popup shows up, tab changes)
 342         /// and before first UI element is highlighted.
 343         /// </summary>
 344         [EditorBrowsable(EditorBrowsableState.Never)]
 345         public void RegisterDefaultLabel()
 346         {
 347             Interop.ControlDevel.DaliAccessibilityBridgeRegisterDefaultLabel(SwigCPtr);
 348             if (NDalicPINVOKE.SWIGPendingException.Pending) throw NDalicPINVOKE.SWIGPendingException.Retrieve();
 349         }
 350
 351         /// <summary>
 352         /// Unregisters component that has been registered previously as a source of an accessibility "default label".
 353         /// The "Default label" is a text that could be read by screen-reader immediately
 354         /// after the navigation context has changed (window activates, popup shows up, tab changes)
 355         /// and before first UI element is highlighted.
 356         /// </summary>
 357         [EditorBrowsable(EditorBrowsableState.Never)]
 358         public void UnregisterDefaultLabel()
 359         {
 360             Interop.ControlDevel.DaliAccessibilityBridgeUnregisterDefaultLabel(SwigCPtr);
 361             if (NDalicPINVOKE.SWIGPendingException.Pending) throw NDalicPINVOKE.SWIGPendingException.Retrieve();
 362         }
 363
 364         [EditorBrowsable(EditorBrowsableState.Never)]
 365         protected override void Dispose(bool disposing)
 366         {
 367             if (disposed)
 368             {
 369                 return;
 370             }
 371
 372             internalName = null;
 373
 374             if (disposing == false)
 375             {
 376                 if (IsNativeHandleInvalid() || SwigCMemOwn == false)
 377                 {
 378                     // at this case, implicit nor explicit dispose is not required. No native object is made.
 379                     disposed = true;
 380                     return;
 381                 }
 382             }
 383
 384             if (disposing)
 385             {
 386                 Unparent();
 387             }
 388
 389             base.Dispose(disposing);
 390         }
 391
 392         [EditorBrowsable(EditorBrowsableState.Never)]
 393         protected static readonly string AccessibilityActivateAction = "activate";
 394         [EditorBrowsable(EditorBrowsableState.Never)]
 395         protected static readonly string AccessibilityReadingSkippedAction = "ReadingSkipped";
 396         [EditorBrowsable(EditorBrowsableState.Never)]
 397         protected static readonly string AccessibilityReadingCancelledAction = "ReadingCancelled";
 398         [EditorBrowsable(EditorBrowsableState.Never)]
 399         protected static readonly string AccessibilityReadingStoppedAction = "ReadingStopped";
 400         [EditorBrowsable(EditorBrowsableState.Never)]
 401         protected static readonly string AccessibilityReadingPausedAction = "ReadingPaused";
 402         [EditorBrowsable(EditorBrowsableState.Never)]
 403         protected static readonly string AccessibilityReadingResumedAction = "ReadingResumed";
 404
 405         [EditorBrowsable(EditorBrowsableState.Never)]
 406         private static readonly string[] AccessibilityActions = {
 407             AccessibilityActivateAction,
 408             AccessibilityReadingSkippedAction,
 409             AccessibilityReadingCancelledAction,
 410             AccessibilityReadingStoppedAction,
 411             AccessibilityReadingPausedAction,
 412             AccessibilityReadingResumedAction,
 413         };
 414
 415         [EditorBrowsable(EditorBrowsableState.Never)]
 416         protected virtual string AccessibilityGetName()
 417         {
 418             return "";
 419         }
 420
 421         [EditorBrowsable(EditorBrowsableState.Never)]
 422         protected virtual string AccessibilityGetDescription()
 423         {
 424             return "";
 425         }
 426
 427         [EditorBrowsable(EditorBrowsableState.Never)]
 428         protected virtual bool AccessibilityDoAction(string name)
 429         {
 430             if (name == AccessibilityActivateAction)
 431             {
 432                 if (ActivateSignal?.Empty() == false)
 433                 {
 434                     ActivateSignal?.Emit();
 435                     return true;
 436                 }
 437                 else
 438                 {
 439                     return OnAccessibilityActivated();
 440                 }
 441             }
 442             else if (name == AccessibilityReadingSkippedAction)
 443             {
 444                 if (ReadingSkippedSignal?.Empty() == false)
 445                 {
 446                     ReadingSkippedSignal?.Emit();
 447                     return true;
 448                 }
 449                 else
 450                 {
 451                     return OnAccessibilityReadingSkipped();
 452                 }
 453             }
 454             else if (name == AccessibilityReadingCancelledAction)
 455             {
 456                 if (ReadingCancelledSignal?.Empty() == false)
 457                 {
 458                     ReadingCancelledSignal?.Emit();
 459                     return true;
 460                 }
 461                 else
 462                 {
 463                     return OnAccessibilityReadingCancelled();
 464                 }
 465             }
 466             else if (name == AccessibilityReadingStoppedAction)
 467             {
 468                 if (ReadingStoppedSignal?.Empty() == false)
 469                 {
 470                     ReadingStoppedSignal?.Emit();
 471                     return true;
 472                 }
 473                 else
 474                 {
 475                     return OnAccessibilityReadingStopped();
 476                 }
 477             }
 478             else if (name == AccessibilityReadingPausedAction)
 479             {
 480                 if (ReadingPausedSignal?.Empty() == false)
 481                 {
 482                     ReadingPausedSignal?.Emit();
 483                     return true;
 484                 }
 485                 else
 486                 {
 487                     return OnAccessibilityReadingPaused();
 488                 }
 489             }
 490             else if (name == AccessibilityReadingResumedAction)
 491             {
 492                 if (ReadingResumedSignal?.Empty() == false)
 493                 {
 494                     ReadingResumedSignal?.Emit();
 495                     return true;
 496                 }
 497                 else
 498                 {
 499                     return OnAccessibilityReadingResumed();
 500                 }
 501             }
 502             else
 503             {
 504                 return false;
 505             }
 506         }
 507
 508         [EditorBrowsable(EditorBrowsableState.Never)]
 509         protected virtual AccessibilityStates AccessibilityCalculateStates()
 510         {
 511             var states = AccessibilityInitialStates;
 512
 513             states[AccessibilityState.Focused] = this.State == States.Focused;
 514             states[AccessibilityState.Enabled] = this.State != States.Disabled;
 515             states[AccessibilityState.Sensitive] = this.Sensitive;
 516
 517             return states;
 518         }
 519
 520         [EditorBrowsable(EditorBrowsableState.Never)]
 521         protected virtual int AccessibilityGetActionCount()
 522         {
 523             return AccessibilityActions.Length;
 524         }
 525
 526         [EditorBrowsable(EditorBrowsableState.Never)]
 527         protected virtual string AccessibilityGetActionName(int index)
 528         {
 529             if (index >= 0 && index < AccessibilityActions.Length)
 530             {
 531                 return AccessibilityActions[index];
 532             }
 533             else
 534             {
 535                 return "";
 536             }
 537         }
 538
 539         [EditorBrowsable(EditorBrowsableState.Never)]
 540         protected virtual bool AccessibilityIsScrollable()
 541         {
 542             return false;
 543         }
 544
 545         [EditorBrowsable(EditorBrowsableState.Never)]
 546         protected virtual bool AccessibilityScrollToChild(View child)
 547         {
 548             return false;
 549         }
 550
 551         /// <summary>
 552         /// This method is called when the control accessibility is activated.<br />
 553         /// Derived classes should override this to perform custom accessibility activation.<br />
 554         /// </summary>
 555         /// <returns>True if this control can perform accessibility activation.</returns>
 556         [EditorBrowsable(EditorBrowsableState.Never)]
 557         protected virtual bool OnAccessibilityActivated()
 558         {
 559             return false;
 560         }
 561
 562         /// <summary>
 563         /// This method is called when reading is skipped.
 564         /// </summary>
 565         /// <returns>True if information was served.</returns>
 566         [EditorBrowsable(EditorBrowsableState.Never)]
 567         protected virtual bool OnAccessibilityReadingSkipped()
 568         {
 569             return false;
 570         }
 571
 572         /// <summary>
 573         /// This method is called when reading is cancelled.
 574         /// </summary>
 575         /// <returns>True if information was served.</returns>
 576         [EditorBrowsable(EditorBrowsableState.Never)]
 577         protected virtual bool OnAccessibilityReadingCancelled()
 578         {
 579             return false;
 580         }
 581
 582         /// <summary>
 583         /// This method is called when reading is stopped.
 584         /// </summary>
 585         /// <returns>True if information was served.</returns>
 586         [EditorBrowsable(EditorBrowsableState.Never)]
 587         protected virtual bool OnAccessibilityReadingStopped()
 588         {
 589             return false;
 590         }
 591
 592         /// <summary>
 593         /// This method is called when reading was paused.
 594         /// </summary>
 595         /// <returns>True if information was served.</returns>
 596         [EditorBrowsable(EditorBrowsableState.Never)]
 597         protected virtual bool OnAccessibilityReadingPaused()
 598         {
 599             return false;
 600         }
 601
 602         /// <summary>
 603         /// This method is called when reading is resumed.
 604         /// </summary>
 605         /// <returns>True if information was served.</returns>
 606         [EditorBrowsable(EditorBrowsableState.Never)]
 607         protected virtual bool OnAccessibilityReadingResumed()
 608         {
 609             return false;
 610         }
 611     }
 612 }