editeng/source/accessibility/AccessibleContextBase.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
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   9  * This file incorporates work covered by the following license notice:
  10  *
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  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 #include <editeng/AccessibleContextBase.hxx>
  21
  22 #include <com/sun/star/accessibility/XAccessibleEventListener.hpp>
  23 #include <com/sun/star/accessibility/AccessibleStateType.hpp>
  24 #include <com/sun/star/accessibility/AccessibleRelationType.hpp>
  25 #include <com/sun/star/lang/IndexOutOfBoundsException.hpp>
  26 #include <com/sun/star/accessibility/AccessibleEventId.hpp>
  27 #include <com/sun/star/accessibility/IllegalAccessibleComponentStateException.hpp>
  28
  29 #include <unotools/accessiblestatesethelper.hxx>
  30 #include <unotools/accessiblerelationsethelper.hxx>
  31 #include <comphelper/accessibleeventnotifier.hxx>
  32 #include <cppuhelper/supportsservice.hxx>
  33 #include <osl/mutex.hxx>
  34
  35 #include <utility>
  36
  37 using namespace ::com::sun::star;
  38 using namespace ::com::sun::star::accessibility;
  39
  40 namespace accessibility {
  41
  42 // internal
  43
  44 AccessibleContextBase::AccessibleContextBase (
  45         const uno::Reference<XAccessible>& rxParent,
  46         const sal_Int16 aRole)
  47     :   WeakComponentImplHelper(MutexOwner::maMutex),
  48         mxParent(rxParent),
  49         msDescription(),
  50         meDescriptionOrigin(NotSet),
  51         msName(),
  52         meNameOrigin(NotSet),
  53         mnClientId(0),
  54         maRole(aRole)
  55 {
  56     // Create the state set.
  57     ::utl::AccessibleStateSetHelper* pStateSet  = new ::utl::AccessibleStateSetHelper ();
  58     mxStateSet = pStateSet;
  59
  60     // Set some states.  Don't use the SetState method because no events
  61     // shall be broadcasted (that is not yet initialized anyway).
  62     pStateSet->AddState (AccessibleStateType::ENABLED);
  63     pStateSet->AddState (AccessibleStateType::SENSITIVE);
  64     pStateSet->AddState (AccessibleStateType::SHOWING);
  65     pStateSet->AddState (AccessibleStateType::VISIBLE);
  66     pStateSet->AddState (AccessibleStateType::FOCUSABLE);
  67     pStateSet->AddState (AccessibleStateType::SELECTABLE);
  68
  69     // Create the relation set.
  70     ::utl::AccessibleRelationSetHelper* pRelationSet = new ::utl::AccessibleRelationSetHelper ();
  71     mxRelationSet = pRelationSet;
  72 }
  73
  74 AccessibleContextBase::~AccessibleContextBase()
  75 {
  76 }
  77
  78 bool AccessibleContextBase::SetState (sal_Int16 aState)
  79 {
  80     ::osl::ClearableMutexGuard aGuard (maMutex);
  81     ::utl::AccessibleStateSetHelper* pStateSet =
  82         static_cast< ::utl::AccessibleStateSetHelper*>(mxStateSet.get());
  83     if ((pStateSet != nullptr) && !pStateSet->contains(aState))
  84     {
  85         pStateSet->AddState (aState);
  86         // Clear the mutex guard so that it is not locked during calls to
  87         // listeners.
  88         aGuard.clear();
  89
  90         // Send event for all states except the DEFUNC state.
  91         if (aState != AccessibleStateType::DEFUNC)
  92         {
  93             uno::Any aNewValue;
  94             aNewValue <<= aState;
  95             CommitChange(
  96                 AccessibleEventId::STATE_CHANGED,
  97                 aNewValue,
  98                 uno::Any());
  99         }
 100         return true;
 101     }
 102     else
 103         return false;
 104 }
 105
 106
 107 bool AccessibleContextBase::ResetState (sal_Int16 aState)
 108 {
 109     ::osl::ClearableMutexGuard aGuard (maMutex);
 110     ::utl::AccessibleStateSetHelper* pStateSet =
 111         static_cast< ::utl::AccessibleStateSetHelper*>(mxStateSet.get());
 112     if ((pStateSet != nullptr) && pStateSet->contains(aState))
 113     {
 114         pStateSet->RemoveState (aState);
 115         // Clear the mutex guard so that it is not locked during calls to listeners.
 116         aGuard.clear();
 117
 118         uno::Any aOldValue;
 119         aOldValue <<= aState;
 120         CommitChange(
 121             AccessibleEventId::STATE_CHANGED,
 122             uno::Any(),
 123             aOldValue);
 124         return true;
 125     }
 126     else
 127         return false;
 128 }
 129
 130
 131 bool AccessibleContextBase::GetState (sal_Int16 aState)
 132 {
 133     ::osl::MutexGuard aGuard (maMutex);
 134     ::utl::AccessibleStateSetHelper* pStateSet =
 135         static_cast< ::utl::AccessibleStateSetHelper*>(mxStateSet.get());
 136     if (pStateSet != nullptr)
 137         return pStateSet->contains(aState);
 138     else
 139         // If there is no state set then return false as a default value.
 140         return false;
 141 }
 142
 143
 144 void AccessibleContextBase::SetRelationSet (
 145     const uno::Reference<XAccessibleRelationSet>& rxNewRelationSet)
 146 {
 147     // Try to emit some meaningful events indicating differing relations in
 148     // both sets.
 149     typedef std::pair<short int,short int> RD;
 150     const RD aRelationDescriptors[] = {
 151         RD(AccessibleRelationType::CONTROLLED_BY, AccessibleEventId::CONTROLLED_BY_RELATION_CHANGED),
 152         RD(AccessibleRelationType::CONTROLLER_FOR, AccessibleEventId::CONTROLLER_FOR_RELATION_CHANGED),
 153         RD(AccessibleRelationType::LABELED_BY, AccessibleEventId::LABELED_BY_RELATION_CHANGED),
 154         RD(AccessibleRelationType::LABEL_FOR, AccessibleEventId::LABEL_FOR_RELATION_CHANGED),
 155         RD(AccessibleRelationType::MEMBER_OF, AccessibleEventId::MEMBER_OF_RELATION_CHANGED),
 156         RD(AccessibleRelationType::INVALID, -1),
 157     };
 158     for (int i=0; aRelationDescriptors[i].first!=AccessibleRelationType::INVALID; i++)
 159         if (mxRelationSet->containsRelation(aRelationDescriptors[i].first)
 160         != rxNewRelationSet->containsRelation(aRelationDescriptors[i].first))
 161         CommitChange (aRelationDescriptors[i].second, uno::Any(), uno::Any());
 162
 163     mxRelationSet = rxNewRelationSet;
 164 }
 165
 166
 167 // XAccessible
 168
 169 uno::Reference< XAccessibleContext> SAL_CALL
 170     AccessibleContextBase::getAccessibleContext()
 171 {
 172     return this;
 173 }
 174
 175
 176 // XAccessibleContext
 177
 178 /** No children.
 179 */
 180 sal_Int32 SAL_CALL
 181        AccessibleContextBase::getAccessibleChildCount()
 182 {
 183     return 0;
 184 }
 185
 186
 187 /** Forward the request to the shape.  Return the requested shape or throw
 188     an exception for a wrong index.
 189 */
 190 uno::Reference<XAccessible> SAL_CALL
 191     AccessibleContextBase::getAccessibleChild (sal_Int32 nIndex)
 192 {
 193     ThrowIfDisposed ();
 194     throw lang::IndexOutOfBoundsException (
 195         "no child with index " + OUString::number(nIndex),
 196         nullptr);
 197 }
 198
 199
 200 uno::Reference<XAccessible> SAL_CALL
 201        AccessibleContextBase::getAccessibleParent()
 202 {
 203     ThrowIfDisposed ();
 204     return mxParent;
 205 }
 206
 207
 208 sal_Int32 SAL_CALL
 209        AccessibleContextBase::getAccessibleIndexInParent()
 210 {
 211     ThrowIfDisposed ();
 212     //  Use a simple but slow solution for now.  Optimize later.
 213
 214     //  Iterate over all the parent's children and search for this object.
 215     if (mxParent.is())
 216     {
 217         uno::Reference<XAccessibleContext> xParentContext (
 218             mxParent->getAccessibleContext());
 219         if (xParentContext.is())
 220         {
 221             sal_Int32 nChildCount = xParentContext->getAccessibleChildCount();
 222             for (sal_Int32 i=0; i<nChildCount; i++)
 223             {
 224                 uno::Reference<XAccessible> xChild (xParentContext->getAccessibleChild (i));
 225                 if (xChild.is())
 226                 {
 227                     uno::Reference<XAccessibleContext> xChildContext = xChild->getAccessibleContext();
 228                     if (xChildContext == static_cast<XAccessibleContext*>(this))
 229                         return i;
 230                 }
 231             }
 232         }
 233     }
 234
 235     //   Return -1 to indicate that this object's parent does not know about the
 236     //   object.
 237     return -1;
 238 }
 239
 240
 241 sal_Int16 SAL_CALL
 242     AccessibleContextBase::getAccessibleRole()
 243 {
 244     ThrowIfDisposed ();
 245     return maRole;
 246 }
 247
 248
 249 OUString SAL_CALL
 250        AccessibleContextBase::getAccessibleDescription()
 251 {
 252     ThrowIfDisposed ();
 253
 254     return msDescription;
 255 }
 256
 257
 258 OUString SAL_CALL
 259        AccessibleContextBase::getAccessibleName()
 260 {
 261     ThrowIfDisposed ();
 262
 263     if (meNameOrigin == NotSet)
 264     {
 265         // Do not send an event because this is the first time it has been
 266         // requested.
 267         msName = CreateAccessibleName();
 268         meNameOrigin = AutomaticallyCreated;
 269     }
 270
 271     return msName;
 272 }
 273
 274
 275 /** Return a copy of the relation set.
 276 */
 277 uno::Reference<XAccessibleRelationSet> SAL_CALL
 278        AccessibleContextBase::getAccessibleRelationSet()
 279 {
 280     ThrowIfDisposed ();
 281
 282     // Create a copy of the relation set and return it.
 283     ::utl::AccessibleRelationSetHelper* pRelationSet =
 284         static_cast< ::utl::AccessibleRelationSetHelper*>(mxRelationSet.get());
 285     if (pRelationSet != nullptr)
 286     {
 287         return uno::Reference<XAccessibleRelationSet> (
 288             new ::utl::AccessibleRelationSetHelper (*pRelationSet));
 289     }
 290     else
 291         return uno::Reference<XAccessibleRelationSet>(nullptr);
 292 }
 293
 294
 295 /** Return a copy of the state set.
 296     Possible states are:
 297         ENABLED
 298         SHOWING
 299         VISIBLE
 300 */
 301 uno::Reference<XAccessibleStateSet> SAL_CALL
 302     AccessibleContextBase::getAccessibleStateSet()
 303 {
 304     ::utl::AccessibleStateSetHelper* pStateSet = nullptr;
 305
 306     if (rBHelper.bDisposed)
 307     {
 308         // We are already disposed!
 309         // Create a new state set that has only set the DEFUNC state.
 310         pStateSet = new ::utl::AccessibleStateSetHelper ();
 311         pStateSet->AddState (AccessibleStateType::DEFUNC);
 312     }
 313     else
 314     {
 315         // Create a copy of the state set and return it.
 316         pStateSet = static_cast< ::utl::AccessibleStateSetHelper*>(mxStateSet.get());
 317
 318         if (pStateSet != nullptr)
 319             pStateSet = new ::utl::AccessibleStateSetHelper (*pStateSet);
 320     }
 321
 322     return uno::Reference<XAccessibleStateSet>(pStateSet);
 323 }
 324
 325
 326 lang::Locale SAL_CALL
 327        AccessibleContextBase::getLocale()
 328 {
 329     ThrowIfDisposed ();
 330     // Delegate request to parent.
 331     if (mxParent.is())
 332     {
 333         uno::Reference<XAccessibleContext> xParentContext (
 334             mxParent->getAccessibleContext());
 335         if (xParentContext.is())
 336             return xParentContext->getLocale ();
 337     }
 338
 339     //  No locale and no parent.  Therefore throw exception to indicate this
 340     //  cluelessness.
 341     throw IllegalAccessibleComponentStateException ();
 342 }
 343
 344
 345 // XAccessibleEventListener
 346
 347 void SAL_CALL AccessibleContextBase::addAccessibleEventListener (
 348         const uno::Reference<XAccessibleEventListener >& rxListener)
 349 {
 350     if (!rxListener.is())
 351         return;
 352
 353     if (rBHelper.bDisposed || rBHelper.bInDispose)
 354     {
 355         uno::Reference<uno::XInterface> x (static_cast<lang::XComponent *>(this), uno::UNO_QUERY);
 356         rxListener->disposing (lang::EventObject (x));
 357     }
 358     else
 359     {
 360         if (!mnClientId)
 361             mnClientId = comphelper::AccessibleEventNotifier::registerClient( );
 362         comphelper::AccessibleEventNotifier::addEventListener( mnClientId, rxListener );
 363     }
 364 }
 365
 366
 367 void SAL_CALL AccessibleContextBase::removeAccessibleEventListener (
 368         const uno::Reference<XAccessibleEventListener >& rxListener )
 369 {
 370     ThrowIfDisposed ();
 371     if (!(rxListener.is() && mnClientId))
 372         return;
 373
 374     sal_Int32 nListenerCount = comphelper::AccessibleEventNotifier::removeEventListener( mnClientId, rxListener );
 375     if ( !nListenerCount )
 376     {
 377         // no listeners anymore
 378         // -> revoke ourself. This may lead to the notifier thread dying (if we were the last client),
 379         // and at least to us not firing any events anymore, in case somebody calls
 380         // NotifyAccessibleEvent, again
 381         comphelper::AccessibleEventNotifier::revokeClient( mnClientId );
 382         mnClientId = 0;
 383     }
 384 }
 385
 386 // XServiceInfo
 387 OUString SAL_CALL AccessibleContextBase::getImplementationName()
 388 {
 389     return "AccessibleContextBase";
 390 }
 391
 392 sal_Bool SAL_CALL AccessibleContextBase::supportsService (const OUString& sServiceName)
 393 {
 394     return cppu::supportsService(this, sServiceName);
 395 }
 396
 397 uno::Sequence< OUString > SAL_CALL
 398        AccessibleContextBase::getSupportedServiceNames()
 399 {
 400     return {
 401         "com.sun.star.accessibility.Accessible",
 402         "com.sun.star.accessibility.AccessibleContext"};
 403 }
 404
 405
 406 // XTypeProvider
 407
 408 uno::Sequence<sal_Int8> SAL_CALL
 409     AccessibleContextBase::getImplementationId()
 410 {
 411     return css::uno::Sequence<sal_Int8>();
 412 }
 413
 414 // internal
 415
 416 void SAL_CALL AccessibleContextBase::disposing()
 417 {
 418     SetState (AccessibleStateType::DEFUNC);
 419
 420     ::osl::MutexGuard aGuard (maMutex);
 421
 422     // Send a disposing to all listeners.
 423     if ( mnClientId )
 424     {
 425         comphelper::AccessibleEventNotifier::revokeClientNotifyDisposing( mnClientId, *this );
 426         mnClientId =  0;
 427     }
 428 }
 429
 430
 431 void AccessibleContextBase::SetAccessibleDescription (
 432     const OUString& rDescription,
 433     StringOrigin eDescriptionOrigin)
 434 {
 435     if (!(eDescriptionOrigin < meDescriptionOrigin
 436         || (eDescriptionOrigin == meDescriptionOrigin && msDescription != rDescription)))
 437         return;
 438
 439     uno::Any aOldValue, aNewValue;
 440     aOldValue <<= msDescription;
 441     aNewValue <<= rDescription;
 442
 443     msDescription = rDescription;
 444     meDescriptionOrigin = eDescriptionOrigin;
 445
 446     CommitChange(
 447         AccessibleEventId::DESCRIPTION_CHANGED,
 448         aNewValue,
 449         aOldValue);
 450 }
 451
 452
 453 void AccessibleContextBase::SetAccessibleName (
 454     const OUString& rName,
 455     StringOrigin eNameOrigin)
 456 {
 457     if (!(eNameOrigin < meNameOrigin
 458         || (eNameOrigin == meNameOrigin && msName != rName)))
 459         return;
 460
 461     uno::Any aOldValue, aNewValue;
 462     aOldValue <<= msName;
 463     aNewValue <<= rName;
 464
 465     msName = rName;
 466     meNameOrigin = eNameOrigin;
 467
 468     CommitChange(
 469         AccessibleEventId::NAME_CHANGED,
 470         aNewValue,
 471         aOldValue);
 472 }
 473
 474
 475 OUString AccessibleContextBase::CreateAccessibleName()
 476 {
 477     return "Empty Name";
 478 }
 479
 480
 481 void AccessibleContextBase::CommitChange (
 482     sal_Int16 nEventId,
 483     const uno::Any& rNewValue,
 484     const uno::Any& rOldValue)
 485 {
 486     // Do not call FireEvent and do not even create the event object when no
 487     // listener has been registered yet.  Creating the event object can
 488     // otherwise lead to a crash.  See issue 93419 for details.
 489     if (mnClientId != 0)
 490     {
 491         AccessibleEventObject aEvent (
 492             static_cast<XAccessibleContext*>(this),
 493             nEventId,
 494             rNewValue,
 495             rOldValue);
 496
 497         FireEvent (aEvent);
 498     }
 499 }
 500
 501
 502 void AccessibleContextBase::FireEvent (const AccessibleEventObject& aEvent)
 503 {
 504     if (mnClientId)
 505         comphelper::AccessibleEventNotifier::addEvent( mnClientId, aEvent );
 506 }
 507
 508
 509 void AccessibleContextBase::ThrowIfDisposed()
 510 {
 511     if (rBHelper.bDisposed || rBHelper.bInDispose)
 512     {
 513         throw lang::DisposedException ("object has been already disposed",
 514             static_cast<uno::XWeak*>(this));
 515     }
 516 }
 517
 518
 519 bool AccessibleContextBase::IsDisposed() const
 520 {
 521     return (rBHelper.bDisposed || rBHelper.bInDispose);
 522 }
 523
 524
 525 void AccessibleContextBase::SetAccessibleRole( sal_Int16 _nRole )
 526 {
 527     maRole = _nRole;
 528 }
 529
 530
 531 } // end of namespace accessibility
 532
 533 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */