<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html> <html lang="en"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <!-- examples-qmlf1legends.qdoc --> <title>Qml F1 Legends | Qt Charts 5.9</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 5.9</td><td ><a href="qtcharts-index.html">Qt Charts</a></td><td ><a href="qtcharts-examples.html">Qt Charts Examples</a></td><td >Qml F1 Legends</td></tr></table><table class="buildversion"><tr> <td id="buildversion" width="100%" align="right">Qt 5.9.4 Reference Documentation</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="#using-list-models-as-data-sources">Using List Models as Data Sources</a></li> </ul> </div> <div class="sidebar-content" id="sidebar-content"></div></div> <h1 class="title">Qml F1 Legends</h1> <span class="subtitle"></span> <!-- $$$qmlf1legends-description --> <div class="descr"> <a name="details"></a> <p class="centerAlign"><img src="images/examples_qmlf1legends.png" alt="" /></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="using-list-models-as-data-sources"></a> <h2 id="using-list-models-as-data-sources">Using List Models as Data Sources</h2> <p>Let's define an empty <a href="qml-qtcharts-chartview.html">ChartView</a> first:</p> <pre class="qml"> <span class="type"><a href="qml-qtcharts-chartview.html">ChartView</a></span> { <span class="name">id</span>: <span class="name">chartView</span> <span class="name">title</span>: <span class="string">"Driver Speeds, lap 1"</span> <span class="name">anchors</span>.fill: <span class="name">parent</span> <span class="name">legend</span>.alignment: <span class="name">Qt</span>.<span class="name">AlignTop</span> <span class="name">animationOptions</span>: <span class="name">ChartView</span>.<span class="name">SeriesAnimations</span> <span class="name">antialiasing</span>: <span class="number">true</span> } </pre> <p>Our XmlListModel uses hard-coded test data. In a real application the data source would be a timing system.</p> <pre class="qml"> <span class="type">XmlListModel</span> { <span class="comment">// Hard-coded test data</span> <span class="name">xml</span>: <span class="string">"<results><row><speedTrap>0</speedTrap><driver>Fittipaldi</driver><speed>104.12</speed></row>"</span> <span class="operator">+</span><span class="string">"<row><speedTrap>0</speedTrap><driver>Stewart</driver><speed>106.12</speed></row>"</span> <span class="operator">+</span><span class="string">"<row><speedTrap>0</speedTrap><driver>Hunt</driver><speed>106.12</speed></row>"</span> ... <span class="name">query</span>: <span class="string">"/results/row"</span> <span class="type">XmlRole</span> { <span class="name">name</span>: <span class="string">"speedTrap"</span>; <span class="name">query</span>: <span class="string">"speedTrap/string()"</span> } <span class="type">XmlRole</span> { <span class="name">name</span>: <span class="string">"driver"</span>; <span class="name">query</span>: <span class="string">"driver/string()"</span> } <span class="type">XmlRole</span> { <span class="name">name</span>: <span class="string">"speed"</span>; <span class="name">query</span>: <span class="string">"speed/string()"</span> } } <span class="comment">// An example XmlListModel containing F1 legend drivers' speeds at speed traps</span> <span class="type">SpeedsXml</span> { <span class="name">id</span>: <span class="name">speedsXml</span> <span class="name">onStatusChanged</span>: { <span class="keyword">if</span> (<span class="name">status</span> <span class="operator">==</span> <span class="name">XmlListModel</span>.<span class="name">Ready</span>) { <span class="name">timer</span>.<span class="name">start</span>(); } } } </pre> <p>The data is parsed with a timer. The line series representing each driver are created on the fly.</p> <pre class="qml"> <span class="comment">// A timer to mimic refreshing the data dynamically</span> <span class="type">Timer</span> { <span class="name">id</span>: <span class="name">timer</span> <span class="name">interval</span>: <span class="number">700</span> <span class="name">repeat</span>: <span class="number">true</span> <span class="name">triggeredOnStart</span>: <span class="number">true</span> <span class="name">running</span>: <span class="number">false</span> <span class="name">onTriggered</span>: { currentIndex++; <span class="keyword">if</span> (<span class="name">currentIndex</span> <span class="operator"><</span> <span class="name">speedsXml</span>.<span class="name">count</span>) { <span class="comment">// Check if there is a series for the data already</span> <span class="comment">// (we are using driver name to identify series)</span> var <span class="name">lineSeries</span> = <span class="name">chartView</span>.<span class="name">series</span>(<span class="name">speedsXml</span>.<span class="name">get</span>(<span class="name">currentIndex</span>).<span class="name">driver</span>); <span class="keyword">if</span> (!<span class="name">lineSeries</span>) { <span class="name">lineSeries</span> <span class="operator">=</span> <span class="name">chartView</span>.<span class="name">createSeries</span>(<span class="name">ChartView</span>.<span class="name">SeriesTypeLine</span>, <span class="name">speedsXml</span>.<span class="name">get</span>(<span class="name">currentIndex</span>).<span class="name">driver</span>); <span class="name">chartView</span>.<span class="name">axisY</span>().<span class="name">min</span> <span class="operator">=</span> <span class="number">0</span>; <span class="name">chartView</span>.<span class="name">axisY</span>().<span class="name">max</span> <span class="operator">=</span> <span class="number">250</span>; <span class="name">chartView</span>.<span class="name">axisY</span>().<span class="name">tickCount</span> <span class="operator">=</span> <span class="number">6</span>; <span class="name">chartView</span>.<span class="name">axisY</span>().<span class="name">titleText</span> <span class="operator">=</span> <span class="string">"speed (kph)"</span>; <span class="name">chartView</span>.<span class="name">axisX</span>().<span class="name">titleText</span> <span class="operator">=</span> <span class="string">"speed trap"</span>; <span class="name">chartView</span>.<span class="name">axisX</span>().<span class="name">labelFormat</span> <span class="operator">=</span> <span class="string">"%.0f"</span>; } <span class="name">lineSeries</span>.<span class="name">append</span>(<span class="name">speedsXml</span>.<span class="name">get</span>(<span class="name">currentIndex</span>).<span class="name">speedTrap</span>, <span class="name">speedsXml</span>.<span class="name">get</span>(<span class="name">currentIndex</span>).<span class="name">speed</span>); <span class="keyword">if</span> (<span class="name">speedsXml</span>.<span class="name">get</span>(<span class="name">currentIndex</span>).<span class="name">speedTrap</span> <span class="operator">></span> <span class="number">3</span>) { <span class="name">chartView</span>.<span class="name">axisX</span>().<span class="name">max</span> <span class="operator">=</span> <span class="name">Number</span>(<span class="name">speedsXml</span>.<span class="name">get</span>(<span class="name">currentIndex</span>).<span class="name">speedTrap</span>) <span class="operator">+</span> <span class="number">1</span>; <span class="name">chartView</span>.<span class="name">axisX</span>().<span class="name">min</span> <span class="operator">=</span> <span class="name">chartView</span>.<span class="name">axisX</span>().<span class="name">max</span> <span class="operator">-</span> <span class="number">5</span>; } <span class="keyword">else</span> { <span class="name">chartView</span>.<span class="name">axisX</span>().<span class="name">max</span> <span class="operator">=</span> <span class="number">5</span>; <span class="name">chartView</span>.<span class="name">axisX</span>().<span class="name">min</span> <span class="operator">=</span> <span class="number">0</span>; } <span class="name">chartView</span>.<span class="name">axisX</span>().<span class="name">tickCount</span> <span class="operator">=</span> <span class="name">chartView</span>.<span class="name">axisX</span>().<span class="name">max</span> <span class="operator">-</span> <span class="name">chartView</span>.<span class="name">axisX</span>().<span class="name">min</span> <span class="operator">+</span> <span class="number">1</span>; } <span class="keyword">else</span> { <span class="comment">// No more data, change x-axis range to show all the data</span> <span class="name">timer</span>.<span class="name">stop</span>(); <span class="name">chartView</span>.<span class="name">animationOptions</span> <span class="operator">=</span> <span class="name">ChartView</span>.<span class="name">AllAnimations</span>; <span class="name">chartView</span>.<span class="name">axisX</span>().<span class="name">min</span> <span class="operator">=</span> <span class="number">0</span>; <span class="name">chartView</span>.<span class="name">axisX</span>().<span class="name">max</span> <span class="operator">=</span> <span class="name">speedsXml</span>.<span class="name">get</span>(<span class="name">currentIndex</span> <span class="operator">-</span> <span class="number">1</span>).<span class="name">speedTrap</span>; } } } </pre> <p>Files:</p> <ul> <li><a href="qtcharts-qmlf1legends-qml-qmlf1legends-speedsxml-qml.html">qmlf1legends/qml/qmlf1legends/SpeedsXml.qml</a></li> <li><a href="qtcharts-qmlf1legends-qml-qmlf1legends-main-qml.html">qmlf1legends/qml/qmlf1legends/main.qml</a></li> <li><a href="qtcharts-qmlf1legends-main-cpp.html">qmlf1legends/main.cpp</a></li> <li><a href="qtcharts-qmlf1legends-qmlf1legends-pro.html">qmlf1legends/qmlf1legends.pro</a></li> <li><a href="qtcharts-qmlf1legends-resources-qrc.html">qmlf1legends/resources.qrc</a></li> </ul> </div> <!-- @@@qmlf1legends --> </div> </div> </div> </div> </div> <div class="footer"> <p> <acronym title="Copyright">©</acronym> 2017 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>