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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 >Line and 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="#combining-charts">Combining Charts</a></li>
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<h1 class="title">Line and BarChart Example</h1>
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<p>In the example we combine a linechart with a barchart and use the category axis as a common axis for both.</p>
<p class="centerAlign"><img src="images/examples_lineandbar.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="combining-charts"></a>
<h2 id="combining-charts">Combining Charts</h2>
<p>Here we create data for our bar series.</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">"Jane"</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">"John"</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">"Axel"</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">"Mary"</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">"Sam"</span>);
<span class="operator">*</span>set0 <span class="operator"><</span><span class="operator"><</span> <span class="number">1</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">2</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">3</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">4</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">5</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">6</span>;
<span class="operator">*</span>set1 <span class="operator"><</span><span class="operator"><</span> <span class="number">5</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">0</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">0</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">4</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">0</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">7</span>;
<span class="operator">*</span>set2 <span class="operator"><</span><span class="operator"><</span> <span class="number">3</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">5</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">8</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">13</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">8</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">5</span>;
<span class="operator">*</span>set3 <span class="operator"><</span><span class="operator"><</span> <span class="number">5</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">6</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">7</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">3</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">4</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">5</span>;
<span class="operator">*</span>set4 <span class="operator"><</span><span class="operator"><</span> <span class="number">9</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">7</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">5</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">3</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">1</span> <span class="operator"><</span><span class="operator"><</span> <span class="number">2</span>;
</pre>
<p>We create a bar series and append sets to it. The first values of each set are grouped together in the first category, the second values in the second category and so on.</p>
<pre class="cpp">
<span class="type"><a href="qbarseries.html">QBarSeries</a></span> <span class="operator">*</span>barseries <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qbarseries.html">QBarSeries</a></span>();
barseries<span class="operator">-</span><span class="operator">></span>append(set0);
barseries<span class="operator">-</span><span class="operator">></span>append(set1);
barseries<span class="operator">-</span><span class="operator">></span>append(set2);
barseries<span class="operator">-</span><span class="operator">></span>append(set3);
barseries<span class="operator">-</span><span class="operator">></span>append(set4);
</pre>
<p>Then we create a line series and add data to it. To make the data match with the barchart, we use the index as an x-value for our line series, so that first point is at (0,value) second at (1,value) and so on.</p>
<pre class="cpp">
<span class="type"><a href="qlineseries.html">QLineSeries</a></span> <span class="operator">*</span>lineseries <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qlineseries.html">QLineSeries</a></span>();
lineseries<span class="operator">-</span><span class="operator">></span>setName(<span class="string">"trend"</span>);
lineseries<span class="operator">-</span><span class="operator">></span>append(<span class="type">QPoint</span>(<span class="number">0</span><span class="operator">,</span> <span class="number">4</span>));
lineseries<span class="operator">-</span><span class="operator">></span>append(<span class="type">QPoint</span>(<span class="number">1</span><span class="operator">,</span> <span class="number">15</span>));
lineseries<span class="operator">-</span><span class="operator">></span>append(<span class="type">QPoint</span>(<span class="number">2</span><span class="operator">,</span> <span class="number">20</span>));
lineseries<span class="operator">-</span><span class="operator">></span>append(<span class="type">QPoint</span>(<span class="number">3</span><span class="operator">,</span> <span class="number">4</span>));
lineseries<span class="operator">-</span><span class="operator">></span>append(<span class="type">QPoint</span>(<span class="number">4</span><span class="operator">,</span> <span class="number">12</span>));
lineseries<span class="operator">-</span><span class="operator">></span>append(<span class="type">QPoint</span>(<span class="number">5</span><span class="operator">,</span> <span class="number">17</span>));
</pre>
<p>Here we create the chart and add both series to it.</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">></span>addSeries(barseries);
chart<span class="operator">-</span><span class="operator">></span>addSeries(lineseries);
chart<span class="operator">-</span><span class="operator">></span>setTitle(<span class="string">"Line and barchart example"</span>);
</pre>
<p>To make the chart show the series properly, we have to create custom axes for the series. If we don't create custom axes, then each series will get scaled to use the maximum area of the chart (like in single series case) and the result will be incorrect. With custom axes we set the range of both series to follow the same axis. For the x-axis we use the <a href="qbarcategoryaxis.html">QBarCategoryAxis</a> and for the y-axis we use QValuesAxis.</p>
<pre class="cpp">
<span class="type">QStringList</span> categories;
categories <span class="operator"><</span><span class="operator"><</span> <span class="string">"Jan"</span> <span class="operator"><</span><span class="operator"><</span> <span class="string">"Feb"</span> <span class="operator"><</span><span class="operator"><</span> <span class="string">"Mar"</span> <span class="operator"><</span><span class="operator"><</span> <span class="string">"Apr"</span> <span class="operator"><</span><span class="operator"><</span> <span class="string">"May"</span> <span class="operator"><</span><span class="operator"><</span> <span class="string">"Jun"</span>;
<span class="type"><a href="qbarcategoryaxis.html">QBarCategoryAxis</a></span> <span class="operator">*</span>axisX <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qbarcategoryaxis.html">QBarCategoryAxis</a></span>();
axisX<span class="operator">-</span><span class="operator">></span>append(categories);
chart<span class="operator">-</span><span class="operator">></span>setAxisX(axisX<span class="operator">,</span> lineseries);
chart<span class="operator">-</span><span class="operator">></span>setAxisX(axisX<span class="operator">,</span> barseries);
axisX<span class="operator">-</span><span class="operator">></span>setRange(<span class="type">QString</span>(<span class="string">"Jan"</span>)<span class="operator">,</span> <span class="type">QString</span>(<span class="string">"Jun"</span>));
<span class="type"><a href="qvalueaxis.html">QValueAxis</a></span> <span class="operator">*</span>axisY <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qvalueaxis.html">QValueAxis</a></span>();
chart<span class="operator">-</span><span class="operator">></span>setAxisY(axisY<span class="operator">,</span> lineseries);
chart<span class="operator">-</span><span class="operator">></span>setAxisY(axisY<span class="operator">,</span> barseries);
axisY<span class="operator">-</span><span class="operator">></span>setRange(<span class="number">0</span><span class="operator">,</span> <span class="number">20</span>);
</pre>
<p>And we also want to show the legend.</p>
<pre class="cpp">
chart<span class="operator">-</span><span class="operator">></span>legend()<span class="operator">-</span><span class="operator">></span>setVisible(<span class="keyword">true</span>);
chart<span class="operator">-</span><span class="operator">></span>legend()<span class="operator">-</span><span class="operator">></span>setAlignment(<span class="type">Qt</span><span class="operator">::</span>AlignBottom);
</pre>
<p>Finally we add the chart onto a view.</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">></span>setRenderHint(<span class="type">QPainter</span><span class="operator">::</span>Antialiasing);
</pre>
<p>Now it is ready to be shown in a window.</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">440</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-lineandbar-main-cpp.html">lineandbar/main.cpp</a></li>
<li><a href="qtcharts-lineandbar-lineandbar-pro.html">lineandbar/lineandbar.pro</a></li>
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