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<?xml version="1.0"?>
<html xmlns="http://www.w3.org/1999/xhtml">
  <head>
    <title>Interfaces - Vala Reference Manual</title>
    <link rel="stylesheet" type="text/css" href="default.css"/>
  </head>
  <body>
    <div class="header">
      <a href="index.html">Vala Reference Manual</a>
    </div>
    <h2>Interfaces</h2>
    <p>Interfaces can be implemented by classes to provide functionality with a common interface. Each class
	can implement multiple interface and interfaces can require other interfaces to be implemented.</p>
    <h3>Interface declarations<a id="declaration"> </a></h3>
    <pre>
		public interface InterfaceName : RequiredInterface &lt;optional&gt;
		{
			&lt;interface members&gt;
		}
		</pre>
    <h3>Methods<a id="methods"> </a></h3>
    <p>Interfaces can contain abstract and non abstract methods.</p>
    <pre>
		public abstract void MethodName ();
		public void MethodName2 ()
		{
			&lt;Implementation&gt;
		}
		</pre>
    <h3>Delegates<a id="delegates"> </a></h3>
    <p>Interfaces can also contain delegates</p>
    <pre>
		public delegate void DelegateName (void* data);
		</pre>
    <h3>Signals<a id="signals"> </a></h3>
    <p>Signals are also supported by interfaces</p>
    <pre>
		public signal void SignalName ();
		</pre>
  </body>
</html>