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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"><html><head><meta name="robots" content="noindex,noarchive">
<title>Qt Toolkit - QCloseEvent Class</title><style type="text/css"><!--
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<h1 align=center>QCloseEvent Class Reference</h1><br clear="all">
<p>
The QCloseEvent class contains parameters that describe a close event.
<a href="#details">More...</a>
<p>
<code>#include <<a href="qevent-h.html">qevent.h</a>></code>
<p>
Inherits <a href="qevent.html">QEvent</a>.
<p><a href="qcloseevent-members.html">List of all member functions.</a>
<h2>Public Members</h2>
<ul>
<li><span class="fn"><a href="qcloseevent.html#a0"><strong>QCloseEvent</strong></a>()</span>
<li><span class="fn">bool<a href="qcloseevent.html#a1"><strong>isAccepted</strong></a>()const</span>
<li><span class="fn">void<a href="qcloseevent.html#a2"><strong>accept</strong></a>()</span>
<li><span class="fn">void<a href="qcloseevent.html#a3"><strong>ignore</strong></a>()</span>
</ul>
<hr><h2><a name="details"></a>Detailed Description</h2>
The QCloseEvent class contains parameters that describe a close event.
<p>
Close events are sent to widgets that the user wants to close, usually
by choosing "Close" from the window menu. They are also sent when you
call <a href="qwidget.html#k5">QWidget::close</a>() to close a widget from inside the program.
<p>Close events contain a special accept flag which tells whether the
receiver wants the widget to be closed. When a widget accepts the close
event, it is <a href="qwidget.html#k3">hidden</a>. If it refuses to
accept the close event, nothing happens.
<p>The <a href="qapplication.html#b9">main widget</a> of the
application is a special case. When it accepts the close event, the
application is immediately <a href="qapplication.html#f0">terminated</a>.
<p>The event handler <a href="qwidget.html#o7">QWidget::closeEvent</a>() receives close events.
<p>The default implementation of this event handler accepts the close event.
This makes Qt <a href="qwidget.html#k3">hide</a> the widget.
<p><pre> void QWidget::closeEvent( <a href="qcloseevent.html">QCloseEvent</a> *e )
{
e-><a href="qcloseevent.html#a2">accept</a>(); // hides the widget
}
</pre>
<p>If you do not want your widget to be hidden, you should reimplement the
event handler.
<p><pre> void MyWidget::closeEvent( <a href="qcloseevent.html">QCloseEvent</a> *e )
{
e-><a href="qcloseevent.html#a3">ignore</a>(); // does not hide the widget
}
</pre>
<p>If you want your widget to be deleted when it is closed, simply delete
it in the close event. In this case, calling <a href="qcloseevent.html#a2">QCloseEvent::accept</a>() or
<a href="qcloseevent.html#a3">QCloseEvent::ignore</a>() makes no difference.<p><strong>Warning:</strong> Be careful. The code below assumes that the widget was created
on the heap using the <code>new</code> operator. Even when the widget has been
created by new doing this is a tricky opreation. Be sure that you cannot
have any other pointers to the widget hanging around.
<p><pre> void MyWidget::closeEvent( <a href="qcloseevent.html">QCloseEvent</a> * )
{
delete this;
}
</pre>
<p><a href="qobject.html">QObject</a> emits the <a href="qobject.html#d2">destroyed()</a> signal
when it is deleted. This is a useful signal if a widget needs to know
when another widget is deleted.
<p>See also: <a href="qwidget.html#k5">QWidget::close</a>(), <a href="qwidget.html#k3">QWidget::hide</a>(), <a href="qobject.html#d2">QObject::destroyed</a>(), <a href="qapplication.html#b9">QApplication::setMainWidget</a>() and <a href="qapplication.html#f0">QApplication::quit</a>().
<hr><h2>Member Function Documentation</h2>
<h3 class="fn"><a name="a0"></a>QCloseEvent::QCloseEvent()</h3>
<p>Constructs a close event object with the accept parameter flag set to FALSE.
<h3 class="fn">void<a name="a2"></a>QCloseEvent::accept()</h3>
<p>Sets the accep flag of the close event object.
<p>Setting the accept flag indicates that the receiver of this event agrees
to close the widget.
<p>The accept flag is not set by default.
<p>If you choose to accept in <a href="qwidget.html#o7">QWidget::closeEvent</a>(), the widget will be
hidden.
<p>See also: <a href="qcloseevent.html#a3">ignore</a>() and <a href="qwidget.html#k3">QWidget::hide</a>().
<h3 class="fn">void<a name="a3"></a>QCloseEvent::ignore()</h3>
<p>Clears the accept flag of the close event object.
<p>Clearing the accept flag indicates that the receiver of this event does not
want the widget to be hidden.
<p>The accept flag is not set by default.
<p>See also: <a href="qcloseevent.html#a2">accept</a>().
<h3 class="fn">bool<a name="a1"></a>QCloseEvent::isAccepted()const</h3>
<p>Returns TRUE if the receiver of the event has agreed to close the widget.
<p>See also: <a href="qcloseevent.html#a2">accept</a>() and <a href="qcloseevent.html#a3">ignore</a>().
<hr><p>
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It was generated from the following files:
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<li>qevent.h: 1998/10/05
<li>qdnd_x11.cpp: 1998/12/17
<li>qevent.cpp: 1999/01/13
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