Custom Chart Example#

This example shows how to customize the appearance of the different elements on a chart.

../_images/examples_customchart.png

Running the Example#

To run the example from Qt Creator , open the Welcome mode and select the example from Examples. For more information, visit Building and Running an Example.

Customizing Charts#

We begin by creating a simple line series and a chart object.

series = QLineSeries()
series << QPointF(0, 6) << QPointF(9, 4) << QPointF(15, 20) << QPointF(25, 12) << QPointF(29, 26)
chart = QChart()
chart.legend().hide()
chart.addSeries(series)

First we customize the series and the chart’s title and background.

# Customize series
pen = QPen(QRgb(0xfdb157))
pen.setWidth(5)
series.setPen(pen)
# Customize chart title
font = QFont()
font.setPixelSize(18)
chart.setTitleFont(font)
chart.setTitleBrush(QBrush(Qt.white))
chart.setTitle("Customchart example")
# Customize chart background
backgroundGradient = QLinearGradient()
backgroundGradient.setStart(QPointF(0, 0))
backgroundGradient.setFinalStop(QPointF(0, 1))
backgroundGradient.setColorAt(0.0, QRgb(0xd2d0d1))
backgroundGradient.setColorAt(1.0, QRgb(0x4c4547))
backgroundGradient.setCoordinateMode(QGradient.ObjectBoundingMode)
chart.setBackgroundBrush(backgroundGradient)
# Customize plot area background
plotAreaGradient = QLinearGradient()
plotAreaGradient.setStart(QPointF(0, 1))
plotAreaGradient.setFinalStop(QPointF(1, 0))
plotAreaGradient.setColorAt(0.0, QRgb(0x555555))
plotAreaGradient.setColorAt(1.0, QRgb(0x55aa55))
plotAreaGradient.setCoordinateMode(QGradient.ObjectBoundingMode)
chart.setPlotAreaBackgroundBrush(plotAreaGradient)
chart.setPlotAreaBackgroundVisible(True)

Then we customize the axes.

axisX = QCategoryAxis()
axisY = QCategoryAxis()
# Customize axis label font
labelsFont = QFont()
labelsFont.setPixelSize(12)
axisX.setLabelsFont(labelsFont)
axisY.setLabelsFont(labelsFont)
# Customize axis colors
axisPen = QPen(QRgb(0xd18952))
axisPen.setWidth(2)
axisX.setLinePen(axisPen)
axisY.setLinePen(axisPen)
# Customize axis label colors
axisBrush = QBrush(Qt.white)
axisX.setLabelsBrush(axisBrush)
axisY.setLabelsBrush(axisBrush)
# Customize grid lines and shades
axisX.setGridLineVisible(False)
axisY.setGridLineVisible(False)
axisY.setShadesPen(Qt.NoPen)
axisY.setShadesBrush(QBrush(QColor(0x99, 0xcc, 0xcc, 0x55)))
axisY.setShadesVisible(True)

Then the axis label values and ranges. Once the axes are ready, we set them to be used by the chart.

axisX.append("low", 10)
axisX.append("optimal", 20)
axisX.append("high", 30)
axisX.setRange(0, 30)
axisY.append("slow", 10)
axisY.append("med", 20)
axisY.append("fast", 30)
axisY.setRange(0, 30)
chart.addAxis(axisX, Qt.AlignBottom)
chart.addAxis(axisY, Qt.AlignLeft)
series.attachAxis(axisX)
series.attachAxis(axisY)

Finally, we create a view containing the chart.

chartView = QChartView(chart)
chartView.setRenderHint(QPainter.Antialiasing)

Now we are ready to show the chart on a main window.

window = QMainWindow()
window.setCentralWidget(chartView)
window.resize(400, 300)
window.show()

Example project @ code.qt.io