src/gui/accessible/qaccessible_mac_carbon.cpp

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  41
  42 static OSStatus applicationEventHandler(EventHandlerCallRef next_ref, EventRef event, void *data);
  43 static EventHandlerUPP applicationEventHandlerUPP = 0;
  44 static EventTypeSpec application_events[] = {
  45     { kEventClassAccessibility,  kEventAccessibleGetChildAtPoint },
  46     { kEventClassAccessibility,  kEventAccessibleGetNamedAttribute }
  47 };
  48
  49 static CFStringRef kObjectQtAccessibility = CFSTR("com.trolltech.qt.accessibility");
  50 static EventHandlerUPP objectCreateEventHandlerUPP = 0;
  51 static EventTypeSpec objectCreateEvents[] = {
  52     { kEventClassHIObject,  kEventHIObjectConstruct },
  53     { kEventClassHIObject,  kEventHIObjectInitialize },
  54     { kEventClassHIObject,  kEventHIObjectDestruct },
  55     { kEventClassHIObject,  kEventHIObjectPrintDebugInfo }
  56 };
  57
  58 static OSStatus accessibilityEventHandler(EventHandlerCallRef next_ref, EventRef event, void *data);
  59 static EventHandlerUPP accessibilityEventHandlerUPP = 0;
  60 static EventTypeSpec accessibilityEvents[] = {
  61     { kEventClassAccessibility,  kEventAccessibleGetChildAtPoint },
  62     { kEventClassAccessibility,  kEventAccessibleGetFocusedChild },
  63     { kEventClassAccessibility,  kEventAccessibleGetAllAttributeNames },
  64     { kEventClassAccessibility,  kEventAccessibleGetNamedAttribute },
  65     { kEventClassAccessibility,  kEventAccessibleSetNamedAttribute },
  66     { kEventClassAccessibility,  kEventAccessibleIsNamedAttributeSettable },
  67     { kEventClassAccessibility,  kEventAccessibleGetAllActionNames },
  68     { kEventClassAccessibility,  kEventAccessiblePerformNamedAction },
  69     { kEventClassAccessibility,  kEventAccessibleGetNamedActionDescription }
  70 };
  71
  72 static void installAcessibilityEventHandler(HIObjectRef hiObject)
  73 {
  74     if (!accessibilityEventHandlerUPP)
  75         accessibilityEventHandlerUPP = NewEventHandlerUPP(accessibilityEventHandler);
  76
  77     InstallHIObjectEventHandler(hiObject, accessibilityEventHandlerUPP,
  78                                         GetEventTypeCount(accessibilityEvents),
  79                                         accessibilityEvents, 0, 0);
  80 }
  81
  82 static OSStatus objectCreateEventHandler(EventHandlerCallRef next_ref, EventRef event, void *data)
  83 {
  84     Q_UNUSED(data)
  85     Q_UNUSED(event)
  86     Q_UNUSED(next_ref)
  87     return noErr;
  88 }
  89
  90 static void registerQtAccessibilityHIObjectSubclass()
  91 {
  92     if (!objectCreateEventHandlerUPP)
  93         objectCreateEventHandlerUPP = NewEventHandlerUPP(objectCreateEventHandler);
  94     OSStatus err = HIObjectRegisterSubclass(kObjectQtAccessibility, 0, 0, objectCreateEventHandlerUPP,
  95                                          GetEventTypeCount(objectCreateEvents), objectCreateEvents, 0, 0);
  96     if (err && err != hiObjectClassExistsErr)
  97         qWarning("qaccessible_mac internal error: Could not register accessibility HIObject subclass");
  98 }
  99
 100 static void installApplicationEventhandler()
 101 {
 102     if (!applicationEventHandlerUPP)
 103         applicationEventHandlerUPP = NewEventHandlerUPP(applicationEventHandler);
 104
 105     OSStatus err = InstallApplicationEventHandler(applicationEventHandlerUPP,
 106                             GetEventTypeCount(application_events), application_events,
 107                             0, 0);
 108
 109     if (err && err != eventHandlerAlreadyInstalledErr)
 110         qWarning("qaccessible_mac internal error: Could not install application accessibility event handler");
 111 }
 112
 113 static void removeEventhandler(EventHandlerUPP eventHandler)
 114 {
 115     if (eventHandler) {
 116         DisposeEventHandlerUPP(eventHandler);
 117         eventHandler = 0;
 118     }
 119 }