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diff --git a/doc/man/man3/qcustomevent.3qt b/doc/man/man3/qcustomevent.3qt new file mode 100644 index 000000000..c1e63790b --- /dev/null +++ b/doc/man/man3/qcustomevent.3qt @@ -0,0 +1,130 @@ +'\" t +.TH QCustomEvent 3qt "2 February 2007" "Trolltech AS" \" -*- nroff -*- +.\" Copyright 1992-2007 Trolltech ASA. All rights reserved. See the +.\" license file included in the distribution for a complete license +.\" statement. +.\" +.ad l +.nh +.SH NAME +QCustomEvent \- Support for custom events +.SH SYNOPSIS +\fC#include <qevent.h>\fR +.PP +Inherits QEvent. +.PP +.SS "Public Members" +.in +1c +.ti -1c +.BI "\fBQCustomEvent\fR ( int type )" +.br +.ti -1c +.BI "\fBQCustomEvent\fR ( Type type, void * data )" +.br +.ti -1c +.BI "void * \fBdata\fR () const" +.br +.ti -1c +.BI "void \fBsetData\fR ( void * data )" +.br +.in -1c +.SH DESCRIPTION +The QCustomEvent class provides support for custom events. +.PP +QCustomEvent is a generic event class for user-defined events. User defined events can be sent to widgets or other QObject instances using QApplication::postEvent() or QApplication::sendEvent(). Subclasses of QObject can easily receive custom events by implementing the QObject::customEvent() event handler function. +.PP +QCustomEvent objects should be created with a type ID that uniquely identifies the event type. To avoid clashes with the Qt-defined events types, the value should be at least as large as the value of the "User" entry in the QEvent::Type enum. +.PP +QCustomEvent contains a generic void* data member that may be used for transferring event-specific data to the receiver. Note that since events are normally delivered asynchronously, the data pointer, if used, must remain valid until the event has been received and processed. +.PP +QCustomEvent can be used as-is for simple user-defined event types, but normally you will want to make a subclass of it for your event types. In a subclass, you can add data members that are suitable for your event type. +.PP +Example: +.PP +.nf +.br + class ColorChangeEvent : public QCustomEvent +.br + { +.br + public: +.br + ColorChangeEvent( QColor color ) +.br + : QCustomEvent( 65432 ), c( color ) {} +.br + QColor color() const { return c; } +.br + private: +.br + QColor c; +.br + }; +.br +.br + // To send an event of this custom event type: +.br +.br + ColorChangeEvent* ce = new ColorChangeEvent( blue ); +.br + QApplication::postEvent( receiver, ce ); // Qt will delete it when done +.br +.br + // To receive an event of this custom event type: +.br +.br + void MyWidget::customEvent( QCustomEvent * e ) +.br + { +.br + if ( e->type() == 65432 ) { // It must be a ColorChangeEvent +.br + ColorChangeEvent* ce = (ColorChangeEvent*)e; +.br + newColor = ce->color(); +.br + } +.br + } +.br +.fi +.PP +See also QWidget::customEvent(), QApplication::notify(), and Event Classes. +.SH MEMBER FUNCTION DOCUMENTATION +.SH "QCustomEvent::QCustomEvent ( int type )" +Constructs a custom event object with event type \fItype\fR. The value of \fItype\fR must be at least as large as QEvent::User. The data pointer is set to 0. +.SH "QCustomEvent::QCustomEvent ( Type type, void * data )" +Constructs a custom event object with the event type \fItype\fR and a pointer to \fIdata\fR. (Note that any int value may safely be cast to QEvent::Type). +.SH "void * QCustomEvent::data () const" +Returns a pointer to the generic event data. +.PP +See also setData(). +.SH "void QCustomEvent::setData ( void * data )" +Sets the generic data pointer to \fIdata\fR. +.PP +See also data(). + +.SH "SEE ALSO" +.BR http://doc.trolltech.com/qcustomevent.html +.BR http://www.trolltech.com/faq/tech.html +.SH COPYRIGHT +Copyright 1992-2007 Trolltech ASA, http://www.trolltech.com. See the +license file included in the distribution for a complete license +statement. +.SH AUTHOR +Generated automatically from the source code. +.SH BUGS +If you find a bug in Qt, please report it as described in +.BR http://doc.trolltech.com/bughowto.html . +Good bug reports help us to help you. Thank you. +.P +The definitive Qt documentation is provided in HTML format; it is +located at $QTDIR/doc/html and can be read using Qt Assistant or with +a web browser. This man page is provided as a convenience for those +users who prefer man pages, although this format is not officially +supported by Trolltech. +.P +If you find errors in this manual page, please report them to +.BR qt-bugs@trolltech.com . +Please include the name of the manual page (qcustomevent.3qt) and the Qt +version (3.3.8). |