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<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 >BarChart Example</td></tr></table><table class="buildversion"><tr>
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<h3><a name="toc">Contents</a></h3>
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<li class="level1"><a href="#running-the-example">Running the Example</a></li>
<li class="level1"><a href="#creating-bar-charts">Creating Bar Charts</a></li>
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<h1 class="title">BarChart Example</h1>
<span class="subtitle"></span>
<!-- $$$barchart-description -->
<div class="descr"> <a name="details"></a>
<p>BarChart shows the data in sets as separate bars, which are in categories.</p>
<p class="centerAlign"><img src="images/examples_barchart.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="creating-bar-charts"></a>
<h2 id="creating-bar-charts">Creating Bar Charts</h2>
<p>The barsets are used in the same way in all barcharts. To illustrate the difference between various barcharts, we use the same data in the examples. Data that the barchart visualizes, is defined by the <a href="qbarset.html">QBarSet</a> instances. Here we create the sets and append data to them. The data is appended here with the &lt;&lt; operator. Alternatively, the append method could be used.</p>
<pre class="cpp">

      <span class="type"><a href="qbarset.html">QBarSet</a></span> <span class="operator">*</span>set0 <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qbarset.html">QBarSet</a></span>(<span class="string">&quot;Jane&quot;</span>);
      <span class="type"><a href="qbarset.html">QBarSet</a></span> <span class="operator">*</span>set1 <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qbarset.html">QBarSet</a></span>(<span class="string">&quot;John&quot;</span>);
      <span class="type"><a href="qbarset.html">QBarSet</a></span> <span class="operator">*</span>set2 <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qbarset.html">QBarSet</a></span>(<span class="string">&quot;Axel&quot;</span>);
      <span class="type"><a href="qbarset.html">QBarSet</a></span> <span class="operator">*</span>set3 <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qbarset.html">QBarSet</a></span>(<span class="string">&quot;Mary&quot;</span>);
      <span class="type"><a href="qbarset.html">QBarSet</a></span> <span class="operator">*</span>set4 <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qbarset.html">QBarSet</a></span>(<span class="string">&quot;Samantha&quot;</span>);

      <span class="operator">*</span>set0 <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">1</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">2</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">3</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">4</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">5</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">6</span>;
      <span class="operator">*</span>set1 <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">5</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">0</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">0</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">4</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">0</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">7</span>;
      <span class="operator">*</span>set2 <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">3</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">5</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">8</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">13</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">8</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">5</span>;
      <span class="operator">*</span>set3 <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">5</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">6</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">7</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">3</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">4</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">5</span>;
      <span class="operator">*</span>set4 <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">9</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">7</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">5</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">3</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">1</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">2</span>;

</pre>
<p>We create the series and append the barsets to it. The series takes ownership of the barsets. The series groups the data from sets to categories. First values of each set are grouped together at first category second value to second category and so on.</p>
<pre class="cpp">

      <span class="type"><a href="qbarseries.html">QBarSeries</a></span> <span class="operator">*</span>series <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qbarseries.html">QBarSeries</a></span>();
      series<span class="operator">-</span><span class="operator">&gt;</span>append(set0);
      series<span class="operator">-</span><span class="operator">&gt;</span>append(set1);
      series<span class="operator">-</span><span class="operator">&gt;</span>append(set2);
      series<span class="operator">-</span><span class="operator">&gt;</span>append(set3);
      series<span class="operator">-</span><span class="operator">&gt;</span>append(set4);

</pre>
<p>Here we create the chart object and add the series to it. We set the title for chart with setTitle and then turn on animations of the series by calling setAnimationOptions(<a href="qchart.html#AnimationOption-enum">QChart::SeriesAnimations</a>)</p>
<pre class="cpp">

      <span class="type"><a href="qchart.html">QChart</a></span> <span class="operator">*</span>chart <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qchart.html">QChart</a></span>();
      chart<span class="operator">-</span><span class="operator">&gt;</span>addSeries(series);
      chart<span class="operator">-</span><span class="operator">&gt;</span>setTitle(<span class="string">&quot;Simple barchart example&quot;</span>);
      chart<span class="operator">-</span><span class="operator">&gt;</span>setAnimationOptions(<span class="type"><a href="qchart.html">QChart</a></span><span class="operator">::</span>SeriesAnimations);

</pre>
<p>To have categories displayed on axis, we need to create a <a href="qbarcategoryaxis.html">QBarCategoryAxis</a> for that. Here we create a category axis with a list of categories and set it to be the x-axis of the chart. The chart takes ownership of axis. For y-axis we use default axis, which is created and scaled to series data by calling createDefaultAxes of the chart. Note that the call for createDefaultAxes must be before we set the category axis. Otherwise the default axis will override the category axis.</p>
<pre class="cpp">

      <span class="type">QStringList</span> categories;
      categories <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;Jan&quot;</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;Feb&quot;</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;Mar&quot;</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;Apr&quot;</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;May&quot;</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;Jun&quot;</span>;
      <span class="type"><a href="qbarcategoryaxis.html">QBarCategoryAxis</a></span> <span class="operator">*</span>axis <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qbarcategoryaxis.html">QBarCategoryAxis</a></span>();
      axis<span class="operator">-</span><span class="operator">&gt;</span>append(categories);
      chart<span class="operator">-</span><span class="operator">&gt;</span>createDefaultAxes();
      chart<span class="operator">-</span><span class="operator">&gt;</span>setAxisX(axis<span class="operator">,</span> series);

</pre>
<p>We also want to show the legend. To do that, we get the legend pointer from the chart and set it to visible. We also place the legend to the bottom of the chart by setting its alignment to Qt::AlignBottom.</p>
<pre class="cpp">

      chart<span class="operator">-</span><span class="operator">&gt;</span>legend()<span class="operator">-</span><span class="operator">&gt;</span>setVisible(<span class="keyword">true</span>);
      chart<span class="operator">-</span><span class="operator">&gt;</span>legend()<span class="operator">-</span><span class="operator">&gt;</span>setAlignment(<span class="type">Qt</span><span class="operator">::</span>AlignBottom);

</pre>
<p>Finally we add the chart onto a view. We also turn on the antialiasing for the chartView.</p>
<pre class="cpp">

      <span class="type"><a href="qchartview.html">QChartView</a></span> <span class="operator">*</span>chartView <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qchartview.html">QChartView</a></span>(chart);
      chartView<span class="operator">-</span><span class="operator">&gt;</span>setRenderHint(<span class="type">QPainter</span><span class="operator">::</span>Antialiasing);

</pre>
<p>The chart is ready to be shown. We set the chart to be central widget of the window. We also set the size for the chart window and show it.</p>
<pre class="cpp">

      <span class="type">QMainWindow</span> window;
      window<span class="operator">.</span>setCentralWidget(chartView);
      window<span class="operator">.</span>resize(<span class="number">420</span><span class="operator">,</span> <span class="number">300</span>);
      window<span class="operator">.</span>show();

</pre>
<p>Files:</p>
<ul>
<li><a href="qtcharts-barchart-main-cpp.html">barchart/main.cpp</a></li>
<li><a href="qtcharts-barchart-barchart-pro.html">barchart/barchart.pro</a></li>
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