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39
40#include "qabstractnativeeventfilter.h"
41#include "qabstracteventdispatcher.h"
42
43QT_BEGIN_NAMESPACE
44
45/*!
46 \class QAbstractNativeEventFilter
47 \inmodule QtCore
48 \since 5.0
49
50 \brief The QAbstractNativeEventFilter class provides an interface for receiving native
51 events, such as MSG or XCB event structs.
52*/
53
54/*!
55 Creates a native event filter.
56
57 By default this doesn't do anything. Remember to install it on the application
58 object.
59*/
60QAbstractNativeEventFilter::QAbstractNativeEventFilter()
61{
62 Q_UNUSED(d);
63}
64
65/*!
66 Destroys the native event filter.
67
68 This automatically removes it from the application.
69*/
70QAbstractNativeEventFilter::~QAbstractNativeEventFilter()
71{
72 QAbstractEventDispatcher *eventDispatcher = QAbstractEventDispatcher::instance();
73 if (eventDispatcher)
74 eventDispatcher->removeNativeEventFilter(filterObj: this);
75}
76
77// ### fixme Qt 6: result will be qintptr *
78/*!
79 \fn bool QAbstractNativeEventFilter::nativeEventFilter(const QByteArray &eventType, void *message, long *result)
80
81 This method is called for every native event.
82
83 \note The filter function here receives native messages,
84 for example, MSG or XCB event structs.
85
86 It is called by the QPA platform plugin. On Windows, it is called by
87 the event dispatcher.
88
89 The type of event \a eventType is specific to the platform plugin chosen at run-time,
90 and can be used to cast \a message to the right type.
91
92 On X11, \a eventType is set to "xcb_generic_event_t", and the \a message can be casted
93 to a xcb_generic_event_t pointer.
94
95 On Windows, \a eventType is set to "windows_generic_MSG" for messages sent to toplevel windows,
96 and "windows_dispatcher_MSG" for system-wide messages such as messages from a registered hot key.
97 In both cases, the \a message can be casted to a MSG pointer.
98 The \a result pointer is only used on Windows, and corresponds to the LRESULT pointer.
99
100 On macOS, \a eventType is set to "mac_generic_NSEvent", and the \a message can be casted to an NSEvent pointer.
101
102 In your reimplementation of this function, if you want to filter
103 the \a message out, i.e. stop it being handled further, return
104 true; otherwise return false.
105
106 \b {Linux example}
107 \snippet code/src_corelib_kernel_qabstractnativeeventfilter.cpp 0
108
109 \b {macOS example}
110
111 mycocoaeventfilter.h:
112 \snippet code/src_corelib_kernel_qabstractnativeeventfilter.h 0
113
114 mycocoaeventfilter.mm:
115 \snippet code/src_corelib_kernel_qabstractnativeeventfilter.mm 0
116
117 myapp.pro:
118 \snippet code/src_corelib_kernel_qabstractnativeeventfilter.pro 0
119*/
120
121QT_END_NAMESPACE
122

source code of qtbase/src/corelib/kernel/qabstractnativeeventfilter.cpp