You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
200 lines
9.7 KiB
200 lines
9.7 KiB
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
|
|
<!-- /home/espenr/tmp/qt-3.3.8-espenr-2499/qt-x11-free-3.3.8/src/kernel/qtimer.cpp:42 -->
|
|
<html>
|
|
<head>
|
|
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
|
|
<title>TQTimer Class</title>
|
|
<style type="text/css"><!--
|
|
fn { margin-left: 1cm; text-indent: -1cm; }
|
|
a:link { color: #004faf; text-decoration: none }
|
|
a:visited { color: #672967; text-decoration: none }
|
|
body { background: #ffffff; color: black; }
|
|
--></style>
|
|
</head>
|
|
<body>
|
|
|
|
<table border="0" cellpadding="0" cellspacing="0" width="100%">
|
|
<tr bgcolor="#E5E5E5">
|
|
<td valign=center>
|
|
<a href="index.html">
|
|
<font color="#004faf">Home</font></a>
|
|
| <a href="classes.html">
|
|
<font color="#004faf">All Classes</font></a>
|
|
| <a href="mainclasses.html">
|
|
<font color="#004faf">Main Classes</font></a>
|
|
| <a href="annotated.html">
|
|
<font color="#004faf">Annotated</font></a>
|
|
| <a href="groups.html">
|
|
<font color="#004faf">Grouped Classes</font></a>
|
|
| <a href="functions.html">
|
|
<font color="#004faf">Functions</font></a>
|
|
</td>
|
|
<td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>TQTimer Class Reference</h1>
|
|
|
|
<p>The TQTimer class provides timer signals and single-shot timers.
|
|
<a href="#details">More...</a>
|
|
<p><tt>#include <<a href="qtimer-h.html">ntqtimer.h</a>></tt>
|
|
<p>Inherits <a href="ntqobject.html">TQObject</a>.
|
|
<p><a href="qtimer-members.html">List of all member functions.</a>
|
|
<h2>Public Members</h2>
|
|
<ul>
|
|
<li class=fn><a href="#TQTimer"><b>TQTimer</b></a> ( TQObject * parent = 0, const char * name = 0 )</li>
|
|
<li class=fn><a href="#~TQTimer"><b>~TQTimer</b></a> ()</li>
|
|
<li class=fn>bool <a href="#isActive"><b>isActive</b></a> () const</li>
|
|
<li class=fn>int <a href="#start"><b>start</b></a> ( int msec, bool sshot = FALSE )</li>
|
|
<li class=fn>void <a href="#changeInterval"><b>changeInterval</b></a> ( int msec )</li>
|
|
<li class=fn>void <a href="#stop"><b>stop</b></a> ()</li>
|
|
<li class=fn>int <a href="#timerId"><b>timerId</b></a> () const</li>
|
|
</ul>
|
|
<h2>Signals</h2>
|
|
<ul>
|
|
<li class=fn>void <a href="#timeout"><b>timeout</b></a> ()</li>
|
|
</ul>
|
|
<h2>Static Public Members</h2>
|
|
<ul>
|
|
<li class=fn>void <a href="#singleShot"><b>singleShot</b></a> ( int msec, TQObject * receiver, const char * member )</li>
|
|
</ul>
|
|
<hr><a name="details"></a><h2>Detailed Description</h2>
|
|
|
|
|
|
The TQTimer class provides timer signals and single-shot timers.
|
|
<p>
|
|
|
|
|
|
<p> It uses <a href="qtimerevent.html">timer events</a> internally to
|
|
provide a more versatile timer. TQTimer is very easy to use:
|
|
create a TQTimer, call <a href="#start">start</a>() to start it and connect its
|
|
<a href="#timeout">timeout</a>() to the appropriate slots. When the time is up it will
|
|
emit the timeout() signal.
|
|
<p> Note that a TQTimer object is destroyed automatically when its
|
|
parent object is destroyed.
|
|
<p> Example:
|
|
<pre>
|
|
TQTimer *timer = new TQTimer( myObject );
|
|
<a href="ntqobject.html#connect">connect</a>( timer, SIGNAL(<a href="#timeout">timeout</a>()), myObject, SLOT(timerDone()) );
|
|
timer-><a href="#start">start</a>( 2000, TRUE ); // 2 seconds single-shot timer
|
|
</pre>
|
|
|
|
<p> You can also use the static <a href="#singleShot">singleShot</a>() function to create a
|
|
single shot timer.
|
|
<p> As a special case, a TQTimer with timeout 0 times out as soon as
|
|
all the events in the window system's event queue have been
|
|
processed.
|
|
<p> This can be used to do heavy work while providing a snappy
|
|
user interface:
|
|
<pre>
|
|
TQTimer *t = new TQTimer( myObject );
|
|
<a href="ntqobject.html#connect">connect</a>( t, SIGNAL(<a href="#timeout">timeout</a>()), SLOT(processOneThing()) );
|
|
t-><a href="#start">start</a>( 0, FALSE );
|
|
</pre>
|
|
|
|
<p> myObject->processOneThing() will be called repeatedly and should
|
|
return quickly (typically after processing one data item) so that
|
|
TQt can deliver events to widgets and stop the timer as soon as it
|
|
has done all its work. This is the traditional way of
|
|
implementing heavy work in GUI applications; multi-threading is
|
|
now becoming available on more and more platforms, and we expect
|
|
that null events will eventually be replaced by threading.
|
|
<p> Note that TQTimer's accuracy depends on the underlying operating
|
|
system and hardware. Most platforms support an accuracy of 20ms;
|
|
some provide more. If TQt is unable to deliver the requested
|
|
number of timer clicks, it will silently discard some.
|
|
<p> An alternative to using TQTimer is to call <a href="ntqobject.html#startTimer">TQObject::startTimer</a>()
|
|
for your object and reimplement the <a href="ntqobject.html#timerEvent">TQObject::timerEvent</a>() event
|
|
handler in your class (which must, of course, inherit <a href="ntqobject.html">TQObject</a>).
|
|
The disadvantage is that <a href="ntqobject.html#timerEvent">timerEvent</a>() does not support such
|
|
high-level features as single-shot timers or signals.
|
|
<p> Some operating systems limit the number of timers that may be
|
|
used; TQt tries to work around these limitations.
|
|
<p>See also <a href="events.html">Event Classes</a> and <a href="time.html">Time and Date</a>.
|
|
|
|
<hr><h2>Member Function Documentation</h2>
|
|
<h3 class=fn><a name="TQTimer"></a>TQTimer::TQTimer ( <a href="ntqobject.html">TQObject</a> * parent = 0, const char * name = 0 )
|
|
</h3>
|
|
Constructs a timer called <em>name</em>, with the parent <em>parent</em>.
|
|
<p> Note that the parent object's destructor will destroy this timer
|
|
object.
|
|
|
|
<h3 class=fn><a name="~TQTimer"></a>TQTimer::~TQTimer ()
|
|
</h3>
|
|
Destroys the timer.
|
|
|
|
<h3 class=fn>void <a name="changeInterval"></a>TQTimer::changeInterval ( int msec )
|
|
</h3>
|
|
Changes the timeout interval to <em>msec</em> milliseconds.
|
|
<p> If the timer signal is pending, it will be stopped and restarted;
|
|
otherwise it will be started.
|
|
<p> <p>See also <a href="#start">start</a>() and <a href="#isActive">isActive</a>().
|
|
|
|
<h3 class=fn>bool <a name="isActive"></a>TQTimer::isActive () const
|
|
</h3>
|
|
|
|
<p> Returns TRUE if the timer is running (pending); otherwise returns
|
|
FALSE.
|
|
|
|
<p>Example: <a href="tutorial1-11.html#x2376">t11/cannon.cpp</a>.
|
|
<h3 class=fn>void <a name="singleShot"></a>TQTimer::singleShot ( int msec, <a href="ntqobject.html">TQObject</a> * receiver, const char * member )<tt> [static]</tt>
|
|
</h3>
|
|
This static function calls a slot after a given time interval.
|
|
<p> It is very convenient to use this function because you do not need
|
|
to bother with a <a href="ntqobject.html#timerEvent">timerEvent</a> or
|
|
to create a local TQTimer object.
|
|
<p> Example:
|
|
<pre>
|
|
#include <<a href="qapplication-h.html">ntqapplication.h</a>>
|
|
#include <<a href="qtimer-h.html">ntqtimer.h</a>>
|
|
|
|
int main( int argc, char **argv )
|
|
{
|
|
<a href="ntqapplication.html">TQApplication</a> a( argc, argv );
|
|
TQTimer::<a href="#singleShot">singleShot</a>( 10*60*1000, &a, SLOT(<a href="ntqapplication.html#quit">quit</a>()) );
|
|
... // create and show your widgets
|
|
return a.<a href="ntqapplication.html#exec">exec</a>();
|
|
}
|
|
</pre>
|
|
|
|
<p> This sample program automatically terminates after 10 minutes (i.e.
|
|
600000 milliseconds).
|
|
<p> The <em>receiver</em> is the receiving object and the <em>member</em> is the
|
|
slot. The time interval is <em>msec</em>.
|
|
|
|
<h3 class=fn>int <a name="start"></a>TQTimer::start ( int msec, bool sshot = FALSE )
|
|
</h3>
|
|
Starts the timer with a <em>msec</em> milliseconds timeout, and returns
|
|
the ID of the timer, or zero when starting the timer failed.
|
|
<p> If <em>sshot</em> is TRUE, the timer will be activated only once;
|
|
otherwise it will continue until it is stopped.
|
|
<p> Any pending timer will be stopped.
|
|
<p> <p>See also <a href="#singleShot">singleShot</a>(), <a href="#stop">stop</a>(), <a href="#changeInterval">changeInterval</a>(), and <a href="#isActive">isActive</a>().
|
|
|
|
<p>Examples: <a href="aclock-example.html#x1204">aclock/aclock.cpp</a>, <a href="dirview-example.html#x1704">dirview/dirview.cpp</a>, <a href="distributor-example.html#x2671">distributor/distributor.ui.h</a>, <a href="forever-example.html#x1053">forever/forever.cpp</a>, <a href="hello-example.html#x1639">hello/hello.cpp</a>, <a href="tutorial1-11.html#x2377">t11/cannon.cpp</a>, and <a href="tutorial1-13.html#x2407">t13/cannon.cpp</a>.
|
|
<h3 class=fn>void <a name="stop"></a>TQTimer::stop ()
|
|
</h3>
|
|
Stops the timer.
|
|
<p> <p>See also <a href="#start">start</a>().
|
|
|
|
<p>Examples: <a href="dirview-example.html#x1705">dirview/dirview.cpp</a>, <a href="tutorial1-11.html#x2378">t11/cannon.cpp</a>, <a href="tutorial1-12.html#x2400">t12/cannon.cpp</a>, and <a href="tutorial1-13.html#x2408">t13/cannon.cpp</a>.
|
|
<h3 class=fn>void <a name="timeout"></a>TQTimer::timeout ()<tt> [signal]</tt>
|
|
</h3>
|
|
|
|
<p> This signal is emitted when the timer is activated.
|
|
|
|
<p>Examples: <a href="aclock-example.html#x1205">aclock/aclock.cpp</a>, <a href="dirview-example.html#x1706">dirview/dirview.cpp</a>, <a href="distributor-example.html#x2672">distributor/distributor.ui.h</a>, <a href="forever-example.html#x1054">forever/forever.cpp</a>, <a href="hello-example.html#x1640">hello/hello.cpp</a>, and <a href="tutorial1-11.html#x2379">t11/cannon.cpp</a>.
|
|
<h3 class=fn>int <a name="timerId"></a>TQTimer::timerId () const
|
|
</h3>
|
|
|
|
<p> Returns the ID of the timer if the timer is running; otherwise returns
|
|
-1.
|
|
|
|
<!-- eof -->
|
|
<hr><p>
|
|
This file is part of the <a href="index.html">TQt toolkit</a>.
|
|
Copyright © 1995-2007
|
|
<a href="http://www.trolltech.com/">Trolltech</a>. All Rights Reserved.<p><address><hr><div align=center>
|
|
<table width=100% cellspacing=0 border=0><tr>
|
|
<td>Copyright © 2007
|
|
<a href="troll.html">Trolltech</a><td align=center><a href="trademarks.html">Trademarks</a>
|
|
<td align=right><div align=right>TQt 3.3.8</div>
|
|
</table></div></address></body>
|
|
</html>
|