<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html> <html lang="en"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <!-- invoke-static.qdoc --> <title>Qt SCXML Invoke Example (Static) | Qt SCXML 5.12.6</title> <link rel="stylesheet" type="text/css" href="style/offline-simple.css" /> <script type="text/javascript"> document.getElementsByTagName("link").item(0).setAttribute("href", "style/offline.css"); // loading style sheet breaks anchors that were jumped to before // so force jumping to anchor again setTimeout(function() { var anchor = location.hash; // need to jump to different anchor first (e.g. none) location.hash = "#"; setTimeout(function() { location.hash = anchor; }, 0); }, 0); </script> </head> <body> <div class="header" id="qtdocheader"> <div class="main"> <div class="main-rounded"> <div class="navigationbar"> <table><tr> <td >Qt 5.12</td><td ><a href="qtscxml-index.html">Qt SCXML</a></td><td ><a href="examples-qtscxml.html">Qt SCXML Examples</a></td><td >Qt SCXML Invoke Example (Static)</td></tr></table><table class="buildversion"><tr> <td id="buildversion" width="100%" align="right"><a href="qtscxml-index.html">Qt 5.12.6 Reference Documentation</a></td> </tr></table> </div> </div> <div class="content"> <div class="line"> <div class="content mainContent"> <div class="sidebar"> <div class="toc"> <h3><a name="toc">Contents</a></h3> <ul> <li class="level1"><a href="#running-the-example">Running the Example</a></li> <li class="level1"><a href="#invoking-the-state-machine">Invoking the State Machine</a></li> <li class="level1"><a href="#compiling-the-state-machine">Compiling the State Machine</a></li> <li class="level1"><a href="#instantiating-the-state-machine">Instantiating the State Machine</a></li> </ul> </div> <div class="sidebar-content" id="sidebar-content"></div></div> <h1 class="title">Qt SCXML Invoke Example (Static)</h1> <span class="subtitle"></span> <!-- $$$invoke-static-brief --> <p>Invokes a compiled nested state machine.</p> <!-- @@@invoke-static --> <!-- $$$invoke-static-description --> <div class="descr"> <a name="details"></a> <p class="centerAlign"><img src="images/invoke-static.png" alt="" /></p><p><i>Invoke Example (Static)</i> demonstrates how to use the <code><invoke></code> element with generated nested state-machines, where the SCXML file is compiled to a C++ class. The <code><invoke></code> element is used to create an instance of an external service.</p> <a name="running-the-example"></a> <h2 id="running-the-example">Running the Example</h2> <p>To run the example from Qt Creator, open the <b>Welcome</b> mode and select the example from <b>Examples</b>. For more information, visit Building and Running an Example.</p> <a name="invoking-the-state-machine"></a> <h2 id="invoking-the-state-machine">Invoking the State Machine</h2> <p>In <i>statemachine.scxml</i>, we specify a state machine with the name <i>Directions</i> of type <i>http://www.w3.org/TR/scxml/</i> to invoke:</p> <pre class="cpp"> <scxml xmlns="http://www.w3.org/2005/07/scxml" version="1.0" name="Directions" initial="anyplace" > <state id="anyplace"> <transition event="goNowhere" target="nowhere"/> <transition event="goSomewhere" target="somewhere"/> <state id="nowhere"/> <state id="somewhere"> <invoke type="http://www.w3.org/TR/scxml/"> <content> <scxml name="anywhere" version="1.0"> <state id="here"> <transition event="goThere" target="there"/> </state> <state id="there"> <transition event="goHere" target="here"/> </state> </scxml> </content> </invoke> </state> </state> </scxml> </pre> <a name="compiling-the-state-machine"></a> <h2 id="compiling-the-state-machine">Compiling the State Machine</h2> <p>We link against the Qt SCXML module by adding the following line to the <i>invoke-static.pro</i> file:</p> <pre class="cpp"> QT += qml scxml </pre> <p>We then specify the state machine to compile:</p> <pre class="cpp"> STATECHARTS = ../invoke-common/statemachine.scxml </pre> <p>The Qt SCXML Compiler, <code>qscxmlc</code>, is run automatically to generate <i>statemachine.h</i> and <i>statemachine.cpp</i>, and to add them to the <code>HEADERS</code> and <code>SOURCES</code> variables for compilation.</p> <a name="instantiating-the-state-machine"></a> <h2 id="instantiating-the-state-machine">Instantiating the State Machine</h2> <p>We instantiate the generated <code>Directions</code> class in the <i>invoke-static.cpp</i> file, as follows:</p> <pre class="cpp"> <span class="preprocessor">#include "statemachine.h"</span> <span class="type">int</span> main(<span class="type">int</span> argc<span class="operator">,</span> <span class="type">char</span> <span class="operator">*</span>argv<span class="operator">[</span><span class="operator">]</span>) { <span class="type">QGuiApplication</span> app(argc<span class="operator">,</span> argv); qmlRegisterType<span class="operator"><</span>Directions<span class="operator">></span>(<span class="string">"Directions"</span><span class="operator">,</span> <span class="number">1</span><span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> <span class="string">"Directions"</span>); <span class="type">QQmlApplicationEngine</span> engine; engine<span class="operator">.</span>load(<span class="type">QUrl</span>(<span class="type">QStringLiteral</span>(<span class="string">"qrc:/invoke-static.qml"</span>))); <span class="keyword">if</span> (engine<span class="operator">.</span>rootObjects()<span class="operator">.</span>isEmpty()) <span class="keyword">return</span> <span class="operator">-</span><span class="number">1</span>; <span class="keyword">return</span> app<span class="operator">.</span>exec(); } </pre> <p>Files:</p> <ul> <li><a href="qtscxml-invoke-static-invoke-static-cpp.html">invoke-static/invoke-static.cpp</a></li> <li><a href="qtscxml-invoke-static-invoke-static-pro.html">invoke-static/invoke-static.pro</a></li> <li><a href="qtscxml-invoke-static-invoke-static-qml.html">invoke-static/invoke-static.qml</a></li> <li><a href="qtscxml-invoke-static-invoke-static-qrc.html">invoke-static/invoke-static.qrc</a></li> <li><a href="qtscxml-invoke-static-statemachine-cpp.html">invoke-static/statemachine.cpp</a></li> <li><a href="qtscxml-invoke-static-statemachine-h.html">invoke-static/statemachine.h</a></li> </ul> </div> <!-- @@@invoke-static --> </div> </div> </div> </div> </div> <div class="footer"> <p> <acronym title="Copyright">©</acronym> 2019 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners.<br/> The documentation provided herein is licensed under the terms of the <a href="http://www.gnu.org/licenses/fdl.html">GNU Free Documentation License version 1.3</a> as published by the Free Software Foundation.<br/> Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property of their respective owners. </p> </div> </body> </html>