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<td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>QSignal Class Reference</h1>
<p>The QSignal class can be used to send signals for classes
that don't inherit QObject.
<a href="#details">More...</a>
<p><tt>#include &lt;<a href="qsignal-h.html">qsignal.h</a>&gt;</tt>
<p>Inherits <a href="qobject.html">QObject</a>.
<p><a href="qsignal-members.html">List of all member functions.</a>
<h2>Public Members</h2>
<ul>
<li class=fn><a href="#QSignal"><b>QSignal</b></a> ( QObject&nbsp;*&nbsp;parent = 0, const&nbsp;char&nbsp;*&nbsp;name = 0 )</li>
<li class=fn><a href="#~QSignal"><b>~QSignal</b></a> ()</li>
<li class=fn>bool <a href="#connect"><b>connect</b></a> ( const&nbsp;QObject&nbsp;*&nbsp;receiver, const&nbsp;char&nbsp;*&nbsp;member )</li>
<li class=fn>bool <a href="#disconnect"><b>disconnect</b></a> ( const&nbsp;QObject&nbsp;*&nbsp;receiver, const&nbsp;char&nbsp;*&nbsp;member = 0 )</li>
<li class=fn>void <a href="#activate"><b>activate</b></a> ()</li>
<li class=fn>bool isBlocked () const &nbsp;<em>(obsolete)</em></li>
<li class=fn>void block ( bool&nbsp;b ) &nbsp;<em>(obsolete)</em></li>
<li class=fn>void setParameter ( int&nbsp;value ) &nbsp;<em>(obsolete)</em></li>
<li class=fn>int parameter () const &nbsp;<em>(obsolete)</em></li>
<li class=fn>void <a href="#setValue"><b>setValue</b></a> ( const&nbsp;QVariant&nbsp;&amp;&nbsp;value )</li>
<li class=fn>QVariant <a href="#value"><b>value</b></a> () const</li>
</ul>
<hr><a name="details"></a><h2>Detailed Description</h2>
The QSignal class can be used to send signals for classes
that don't inherit <a href="qobject.html">QObject</a>.
<p>
<p> If you want to send signals from a class that does not inherit
QObject, you can create an internal QSignal object to emit the
signal. You must also provide a function that connects the signal
to an outside object slot. This is how we have implemented
signals in the <a href="qmenudata.html">QMenuData</a> class, which is not a QObject.
<p> In general, we recommend inheriting QObject instead. QObject
provides much more functionality.
<p> You can set a single <a href="qvariant.html">QVariant</a> parameter for the signal with
<a href="#setValue">setValue</a>().
<p> Note that QObject is a <em>private</em> base class of QSignal, i.e. you
cannot call any QObject member functions from a QSignal object.
<p> Example:
<pre>
#include &lt;<a href="qsignal-h.html">qsignal.h</a>&gt;
class MyClass
{
public:
MyClass();
~MyClass();
void doSomething();
void connect( <a href="qobject.html">QObject</a> *receiver, const char *member );
private:
QSignal *sig;
};
MyClass::MyClass()
{
sig = new QSignal;
}
MyClass::~MyClass()
{
delete sig;
}
void MyClass::doSomething()
{
// ... does something
sig-&gt;<a href="#activate">activate</a>(); // emits the signal
}
void MyClass::connect( <a href="qobject.html">QObject</a> *receiver, const char *member )
{
sig-&gt;<a href="#connect">connect</a>( receiver, member );
}
</pre>
<p>See also <a href="io.html">Input/Output and Networking</a> and <a href="misc.html">Miscellaneous Classes</a>.
<hr><h2>Member Function Documentation</h2>
<h3 class=fn><a name="QSignal"></a>QSignal::QSignal ( <a href="qobject.html">QObject</a>&nbsp;*&nbsp;parent = 0, const&nbsp;char&nbsp;*&nbsp;name = 0 )
</h3>
Constructs a signal object called <em>name</em>, with the parent object
<em>parent</em>. These arguments are passed directly to <a href="qobject.html">QObject</a>.
<h3 class=fn><a name="~QSignal"></a>QSignal::~QSignal ()
</h3>
Destroys the signal. All connections are removed, as is the case
with all QObjects.
<h3 class=fn>void <a name="activate"></a>QSignal::activate ()
</h3>
<p> Emits the signal. If the platform supports <a href="qvariant.html">QVariant</a> and a
parameter has been set with <a href="#setValue">setValue</a>(), this value is passed in
the signal.
<h3 class=fn>void <a name="block"></a>QSignal::block ( bool&nbsp;b )
</h3>
<b>This function is obsolete.</b> It is provided to keep old source working. We strongly advise against using it in new code.
<p> Blocks the signal if <em>b</em> is TRUE, or unblocks the signal if <em>b</em> is FALSE.
<p> An activated signal disappears into hyperspace if it is blocked.
<p> <p>See also <a href="#isBlocked">isBlocked</a>(), <a href="#activate">activate</a>(), and <a href="qobject.html#blockSignals">QObject::blockSignals</a>().
<h3 class=fn>bool <a name="connect"></a>QSignal::connect ( const&nbsp;<a href="qobject.html">QObject</a>&nbsp;*&nbsp;receiver, const&nbsp;char&nbsp;*&nbsp;member )
</h3>
Connects the signal to <em>member</em> in object <em>receiver</em>.
<p> <p>See also <a href="#disconnect">disconnect</a>() and <a href="qobject.html#connect">QObject::connect</a>().
<h3 class=fn>bool <a name="disconnect"></a>QSignal::disconnect ( const&nbsp;<a href="qobject.html">QObject</a>&nbsp;*&nbsp;receiver, const&nbsp;char&nbsp;*&nbsp;member = 0 )
</h3>
Disonnects the signal from <em>member</em> in object <em>receiver</em>.
<p> <p>See also <a href="#connect">connect</a>() and <a href="qobject.html#disconnect">QObject::disconnect</a>().
<h3 class=fn>bool <a name="isBlocked"></a>QSignal::isBlocked () const
</h3>
<b>This function is obsolete.</b> It is provided to keep old source working. We strongly advise against using it in new code.
<p> Returns TRUE if the signal is blocked, or FALSE if it is not blocked.
<p> The signal is not blocked by default.
<p> <p>See also <a href="#block">block</a>() and <a href="qobject.html#signalsBlocked">QObject::signalsBlocked</a>().
<h3 class=fn>int <a name="parameter"></a>QSignal::parameter () const
</h3> <b>This function is obsolete.</b> It is provided to keep old source working. We strongly advise against using it in new code.
<h3 class=fn>void <a name="setParameter"></a>QSignal::setParameter ( int&nbsp;value )
</h3> <b>This function is obsolete.</b> It is provided to keep old source working. We strongly advise against using it in new code.
<h3 class=fn>void <a name="setValue"></a>QSignal::setValue ( const&nbsp;<a href="qvariant.html">QVariant</a>&nbsp;&amp;&nbsp;value )
</h3>
Sets the signal's parameter to <em>value</em>
<h3 class=fn><a href="qvariant.html">QVariant</a> <a name="value"></a>QSignal::value () const
</h3>
Returns the signal's parameter
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