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  45 <div class="title">Signals</div>  </div>
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  48
  49 <p>Use sigc::signal::connect() with <a class="el" href="group__mem__fun.html#ga6ed5c519845b36eb7c6461ebd2a073c9" title="Creates a functor of type sigc::mem_functor which wraps a method. ">sigc::mem_fun()</a> and <a class="el" href="group__ptr__fun.html#ga203dd1ac5747cf2f3d2b2d590ad32e82" title="Creates a functor of type sigc::pointer_functor which wraps an existing non-member function...">sigc::ptr_fun()</a> to connect a method or function with a signal.
  50 <a href="#details">More...</a></p>
  51 <table class="memberdecls">
  52 <tr class="heading"><td colspan="2"><h2 class="groupheader"><a name="nested-classes"></a>
  53 Classes</h2></td></tr>
  54 <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">struct &#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="structsigc_1_1connection.html">sigc::connection</a></td></tr>
  55 <tr class="memdesc:"><td class="mdescLeft">&#160;</td><td class="mdescRight">Convinience class for safe disconnection.  <a href="structsigc_1_1connection.html#details">More...</a><br /></td></tr>
  56 <tr class="separator:"><td class="memSeparator" colspan="2">&#160;</td></tr>
  57 <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">class &#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="classsigc_1_1signal.html">sigc::signal&lt; T_return, T_arg &gt;</a></td></tr>
  58 <tr class="memdesc:"><td class="mdescLeft">&#160;</td><td class="mdescRight">signal can be used to connect() slots that are invoked during subsequent calls to emit().  <a href="classsigc_1_1signal.html#details">More...</a><br /></td></tr>
  59 <tr class="separator:"><td class="memSeparator" colspan="2">&#160;</td></tr>
  60 <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">class &#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="classsigc_1_1signal_3_01T__return_07T__arg_8_8_8_08_4_1_1accumulated.html">sigc::signal&lt; T_return(T_arg...)&gt;::accumulated&lt; T_accumulator &gt;</a></td></tr>
  61 <tr class="memdesc:"><td class="mdescLeft">&#160;</td><td class="mdescRight">Like <a class="el" href="classsigc_1_1signal.html" title="signal can be used to connect() slots that are invoked during subsequent calls to emit()...">sigc::signal</a> but the additional template parameter <em>T_accumulator</em> defines the accumulator type that should be used.  <a href="classsigc_1_1signal_3_01T__return_07T__arg_8_8_8_08_4_1_1accumulated.html#details">More...</a><br /></td></tr>
  62 <tr class="separator:"><td class="memSeparator" colspan="2">&#160;</td></tr>
  63 <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">struct &#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="structsigc_1_1signal__base.html">sigc::signal_base</a></td></tr>
  64 <tr class="memdesc:"><td class="mdescLeft">&#160;</td><td class="mdescRight">Base class for the <a class="el" href="classsigc_1_1signal.html" title="signal can be used to connect() slots that are invoked during subsequent calls to emit()...">sigc::signal</a># templates.  <a href="structsigc_1_1signal__base.html#details">More...</a><br /></td></tr>
  65 <tr class="separator:"><td class="memSeparator" colspan="2">&#160;</td></tr>
  66 <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">class &#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="classsigc_1_1signal__with__accumulator.html">sigc::signal_with_accumulator&lt; T_return, T_accumulator, T_arg &gt;</a></td></tr>
  67 <tr class="memdesc:"><td class="mdescLeft">&#160;</td><td class="mdescRight">Signal declaration.  <a href="classsigc_1_1signal__with__accumulator.html#details">More...</a><br /></td></tr>
  68 <tr class="separator:"><td class="memSeparator" colspan="2">&#160;</td></tr>
  69 <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">struct &#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="structsigc_1_1slot__const__iterator.html">sigc::slot_const_iterator&lt; T_slot &gt;</a></td></tr>
  70 <tr class="memdesc:"><td class="mdescLeft">&#160;</td><td class="mdescRight">STL-style const iterator for <a class="el" href="structsigc_1_1slot__list.html" title="STL-style list interface for sigc::signal#. ">slot_list</a>.  <a href="structsigc_1_1slot__const__iterator.html#details">More...</a><br /></td></tr>
  71 <tr class="separator:"><td class="memSeparator" colspan="2">&#160;</td></tr>
  72 <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">struct &#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="structsigc_1_1slot__iterator.html">sigc::slot_iterator&lt; T_slot &gt;</a></td></tr>
  73 <tr class="memdesc:"><td class="mdescLeft">&#160;</td><td class="mdescRight">STL-style iterator for <a class="el" href="structsigc_1_1slot__list.html" title="STL-style list interface for sigc::signal#. ">slot_list</a>.  <a href="structsigc_1_1slot__iterator.html#details">More...</a><br /></td></tr>
  74 <tr class="separator:"><td class="memSeparator" colspan="2">&#160;</td></tr>
  75 <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">struct &#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="structsigc_1_1slot__list.html">sigc::slot_list&lt; T_slot &gt;</a></td></tr>
  76 <tr class="memdesc:"><td class="mdescLeft">&#160;</td><td class="mdescRight">STL-style list interface for <a class="el" href="classsigc_1_1signal.html" title="signal can be used to connect() slots that are invoked during subsequent calls to emit()...">sigc::signal</a>#.  <a href="structsigc_1_1slot__list.html#details">More...</a><br /></td></tr>
  77 <tr class="separator:"><td class="memSeparator" colspan="2">&#160;</td></tr>
  78 <tr class="memitem:"><td class="memItemLeft" align="right" valign="top">struct &#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="structsigc_1_1trackable.html">sigc::trackable</a></td></tr>
  79 <tr class="memdesc:"><td class="mdescLeft">&#160;</td><td class="mdescRight">Base class for objects with auto-disconnection.  <a href="structsigc_1_1trackable.html#details">More...</a><br /></td></tr>
  80 <tr class="separator:"><td class="memSeparator" colspan="2">&#160;</td></tr>
  81 </table>
  82 <a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2>
  83 <p>Use sigc::signal::connect() with <a class="el" href="group__mem__fun.html#ga6ed5c519845b36eb7c6461ebd2a073c9" title="Creates a functor of type sigc::mem_functor which wraps a method. ">sigc::mem_fun()</a> and <a class="el" href="group__ptr__fun.html#ga203dd1ac5747cf2f3d2b2d590ad32e82" title="Creates a functor of type sigc::pointer_functor which wraps an existing non-member function...">sigc::ptr_fun()</a> to connect a method or function with a signal. </p>
  84 <div class="fragment"><div class="line">signal_clicked.connect( <a class="code" href="group__mem__fun.html#ga6ed5c519845b36eb7c6461ebd2a073c9">sigc::mem_fun</a>(*<span class="keyword">this</span>, &amp;MyWindow::on_clicked) );</div>
  85 </div><!-- fragment --><p>When the signal is emitted your method will be called.</p>
  86 <p>signal::connect() returns a connection, which you can later use to disconnect your method. If the type of your object inherits from <a class="el" href="structsigc_1_1trackable.html" title="Base class for objects with auto-disconnection. ">sigc::trackable</a> the method is disconnected automatically when your object is destroyed.</p>
  87 <p>When signals are copied they share the underlying information, so you can have a protected/private <a class="el" href="classsigc_1_1signal.html" title="signal can be used to connect() slots that are invoked during subsequent calls to emit()...">sigc::signal</a> member and a public accessor method. A <a class="el" href="classsigc_1_1signal.html" title="signal can be used to connect() slots that are invoked during subsequent calls to emit()...">sigc::signal</a> is a kind of reference-counting pointer. It's similar to std::shared_ptr&lt;&gt;, although <a class="el" href="classsigc_1_1signal.html" title="signal can be used to connect() slots that are invoked during subsequent calls to emit()...">sigc::signal</a> is restricted to holding a pointer to a sigc::internal::signal_impl object that contains the implementation of the signal.</p>
  88 <div class="fragment"><div class="line"><span class="keyword">class </span>MyClass</div>
  89 <div class="line">{</div>
  90 <div class="line"><span class="keyword">public</span>:</div>
  91 <div class="line">  <span class="keyword">using</span> MySignalType = <a class="code" href="classsigc_1_1signal.html">sigc::signal&lt;void()&gt;</a>;</div>
  92 <div class="line">  MySignalType get_my_signal() { <span class="keywordflow">return</span> m_my_signal; }</div>
  93 <div class="line"><span class="keyword">private</span>:</div>
  94 <div class="line">  MySignalType m_my_signal;</div>
  95 <div class="line">};</div>
  96 </div><!-- fragment --><p>signal and slot objects provide the core functionality of this library. A slot is a container for an arbitrary functor. A signal is a list of slots that are executed on emission. For compile time type safety a list of template arguments must be provided for the signal template that determines the parameter list for emission. Functors and closures are converted into slots implicitly on connection, triggering compiler errors if the given functor or closure cannot be invoked with the parameter list of the signal to connect to.</p>
  97 <p>Almost any functor with the correct signature can be converted to a <a class="el" href="classsigc_1_1slot.html" title="Converts an arbitrary functor to a unified type which is opaque. ">sigc::slot</a> and connected to a signal. See <a class="el" href="group__slot.html">Slots</a> and sigc::signal::connect(). </p>
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