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Qt Graphs Migration from Qt Charts

The API and functionality between Qt Charts and Qt Graphs is slightly different. This article explains the differences between the API of both Qt Charts to Qt Graphs:

QML Import Statement

The import statement in Qt Charts:

import QtCharts

has to be changed to:

import QtGraphs

for Qt Graphs.

CMake Module Inclusion

The inclusion in Qt Charts:

find_package(Qt6 REQUIRED COMPONENTS Charts)
target_link_libraries(mytarget PRIVATE Qt6::Charts)

has to be changed to:

find_package(Qt6 REQUIRED COMPONENTS Graphs)
target_link_libraries(mytarget PRIVATE Qt6::Graphs)

for Qt Graphs.

Qmake Module Inclusion

The inclusion in Qt Charts:

QT += charts

has to be changed to:

QT += graphs

for Qt Graphs.

Features missing in Qt Graphs

These features are missing in Qt Graphs in 6.8 release:

  • Qt Graphs Widgets
  • Candlestick charts
  • Box-and-whiskers chart
  • Titles and legends
  • Log value axis
  • Polar chart view

Theme APIs

The theming between 2D and 3D graphs is unified, for the theme settings, see GraphsTheme.

The generic color scheme of the whole graph is now controlled by a color scheme property, and series colors by a theme property. If color scheme is not explicitly set, it will follow the desktop theming (Light/Dark).

Enums

In Qt Graphs 2D, all the enums are implemented as scoped enums, for example, for the PieSlice.LabelOutside in Qt Charts, the corresponding enum in Qt Graphs 2D is PieSlice.LabelPosition.Outside.

Migrating chart series in QML

This section gives the examples of how to migrate you code with Qt Charts to the Qt Graphs 2D.

Migrating Area series

These code samples implement similar charts:

With Qt Charts:

ChartView {
    anchors.fill: parent
    ValueAxis {
        id: valueAxisX
        max: 8
    }

    ValueAxis {
        id: valueAxisY
        max: 4
    }

    AreaSeries {
        axisX: valueAxisX
        axisY: valueAxisY
        upperSeries: LineSeries {
            XYPoint { x: 0; y: 2 }
            XYPoint { x: 1; y: 3.5 }
            XYPoint { x: 2; y: 3.8 }
        }
        lowerSeries: LineSeries {
            XYPoint { x: 0.4; y: 1.5 }
            XYPoint { x: 1; y: 2.5 }
            XYPoint { x: 2.4; y: 3 }
        }
    }
}

With Qt Graphs:

GraphsView {
    anchors.fill: parent
    axisX: ValueAxis {
        id: xAxis
        max: 8
        tickInterval: 2.0
    }

    axisY: ValueAxis {
        id: yAxis
        max: 4
        tickInterval: 1.0
    }

    AreaSeries {
        upperSeries: LineSeries {
            XYPoint { x: 0; y: 2 }
            XYPoint { x: 1; y: 3.5 }
            XYPoint { x: 2; y: 3.8 }
        }

        lowerSeries: LineSeries {
            XYPoint { x: 0.4; y: 1.5 }
            XYPoint { x: 1; y: 2.5 }
            XYPoint { x: 2.4; y: 3 }
        }
    }
}

Migrating Bar series

With Qt Charts:

import QtQuick
import QtCharts

ChartView {
    BarSeries {
        id: mySeries
        axisX: BarCategoryAxis { categories: ["2007", "2008", "2009", "2010", "2011", "2012" ] }
        BarSet { label: "Bob"; values: [2, 2, 3, 4, 5, 6] }
        BarSet { label: "Susan"; values: [5, 1, 2, 4, 1, 7] }
        BarSet { label: "James"; values: [3, 5, 8, 13, 5, 8] }
    }
}

With Qt Graphs:

GraphsView {
    axisX: BarCategoryAxis { categories: ["2007", "2008", "2009", "2010", "2011", "2012" ] }

    BarSeries {
        id: mySeries
        BarSet { label: "Bob"; values: [2, 2, 3, 4, 5, 6] }
        BarSet { label: "Susan"; values: [5, 1, 2, 4, 1, 7] }
        BarSet { label: "James"; values: [3, 5, 8, 13, 5, 8] }
    }
}

Migrating Donut series

With Qt Charts:

import QtQuick
import QtCharts

ChartView {
    PieSeries {
        id: pieOuter
        size: 0.96
        holeSize: 0.7
        PieSlice { id: slice; label: "Alpha"; value: 19511; color: "#99CA53" }
        PieSlice { label: "Epsilon"; value: 11105; color: "#209FDF" }
        PieSlice { label: "Psi"; value: 9352; color: "#F6A625" }
    }

    PieSeries {
        id: pieInner
        size: 0.7
        holeSize: 0.25

        PieSlice { label: "Materials"; value: 10334; color: "#B9DB8A" }
        PieSlice { label: "Employee"; value: 3066; color: "#DCEDC4" }
        PieSlice { label: "Logistics"; value: 6111; color: "#F3F9EB" }

        PieSlice { label: "Materials"; value: 7371; color: "#63BCE9" }
        PieSlice { label: "Employee"; value: 2443; color: "#A6D9F2" }
        PieSlice { label: "Logistics"; value: 1291; color: "#E9F5FC" }

        PieSlice { label: "Materials"; value: 4022; color: "#F9C36C" }
        PieSlice { label: "Employee"; value: 3998; color: "#FCE1B6" }
        PieSlice { label: "Logistics"; value: 1332; color: "#FEF5E7" }
    }

    Component.onCompleted: {
        // Set the common slice properties dynamically for convenience
        for (var i = 0; i < pieOuter.count; i++) {
            pieOuter.at(i).labelPosition = PieSlice.LabelOutside;
            pieOuter.at(i).labelVisible = true;
            pieOuter.at(i).borderWidth = 3;
        }
        for (var i = 0; i < pieInner.count; i++) {
            pieInner.at(i).labelPosition = PieSlice.LabelInsideNormal;
            pieInner.at(i).labelVisible = true;
            pieInner.at(i).borderWidth = 2;
        }
    }
}

With Qt Graphs:

GraphsView {
    PieSeries {
        id: pieOuter
        pieSize: 0.96
        holeSize: 0.7
        PieSlice { id: slice; label: "Alpha"; value: 19511; color: "#99CA53" }
        PieSlice { label: "Epsilon"; value: 11105; color: "#209FDF" }
        PieSlice { label: "Psi"; value: 9352; color: "#F6A625" }
    }

    PieSeries {
        id: pieInner
        pieSize: 0.7
        holeSize: 0.25

        PieSlice { label: "Materials"; value: 10334; color: "#B9DB8A" }
        PieSlice { label: "Employee"; value: 3066; color: "#DCEDC4" }
        PieSlice { label: "Logistics"; value: 6111; color: "#F3F9EB" }

        PieSlice { label: "Materials"; value: 7371; color: "#63BCE9" }
        PieSlice { label: "Employee"; value: 2443; color: "#A6D9F2" }
        PieSlice { label: "Logistics"; value: 1291; color: "#E9F5FC" }

        PieSlice { label: "Materials"; value: 4022; color: "#F9C36C" }
        PieSlice { label: "Employee"; value: 3998; color: "#FCE1B6" }
        PieSlice { label: "Logistics"; value: 1332; color: "#FEF5E7" }
    }

    Component.onCompleted: {
        // Set the common slice properties dynamically for convenience
        for (var i = 0; i < pieOuter.count; i++) {
            pieOuter.at(i).labelPosition = PieSlice.LabelPosition.Outside;
            pieOuter.at(i).labelVisible = true;
            pieOuter.at(i).borderWidth = 3;
        }
        for (var i = 0; i < pieInner.count; i++) {
            pieInner.at(i).labelPosition = PieSlice.LabelPosition.InsideNormal;
            pieInner.at(i).labelVisible = true;
            pieInner.at(i).borderWidth = 2;
        }
    }
}

Migrating Line series

With Qt Charts:

ChartView {
    LineSeries {
        XYPoint { x: 0; y: 0 }
        XYPoint { x: 1.1; y: 2.1 }
        XYPoint { x: 1.9; y: 3.3 }
        XYPoint { x: 2.1; y: 2.1 }
        XYPoint { x: 2.9; y: 4.9 }
        XYPoint { x: 3.4; y: 3.0 }
        XYPoint { x: 4.1; y: 3.3 }
    }
}

With Qt Graphs:

GraphsView {
    // Graphs don't calculate a visible range for axes.
    // You should define the visible range explicitly.
    axisX: ValueAxis {
        id: xAxis
        max: 4.1
    }
    axisY: ValueAxis {
        id: yAxis
        max: 4.9
    }

    LineSeries {
        XYPoint { x: 0; y: 0 }
        XYPoint { x: 1.1; y: 2.1 }
        XYPoint { x: 1.9; y: 3.3 }
        XYPoint { x: 2.1; y: 2.1 }
        XYPoint { x: 2.9; y: 4.9 }
        XYPoint { x: 3.4; y: 3.0 }
        XYPoint { x: 4.1; y: 3.3 }
    }
}

Migrating Pie series

With Qt Charts:

ChartView {
    property variant othersSlice: 0

    PieSeries {
        id: pieSeries
        PieSlice { label: "Volkswagen"; value: 13.5 }
        PieSlice { label: "Toyota"; value: 10.9 }
        PieSlice { label: "Ford"; value: 8.6 }
        PieSlice { label: "Skoda"; value: 8.2 }
        PieSlice { label: "Volvo"; value: 6.8 }
    }

    Component.onCompleted: {
        othersSlice = pieSeries.append("Others", 52.0);
        pieSeries.find("Volkswagen").exploded = true;
    }
}

With Qt Graphs:

GraphsView {
    property variant othersSlice: 0

    PieSeries {
        id: pieSeries
        PieSlice { label: "Volkswagen"; value: 13.5 }
        PieSlice { label: "Toyota"; value: 10.9 }
        PieSlice { label: "Ford"; value: 8.6 }
        PieSlice { label: "Skoda"; value: 8.2 }
        PieSlice { label: "Volvo"; value: 6.8 }
    }

    Component.onCompleted: {
        othersSlice = pieSeries.append("Others", 52.0);
        pieSeries.find("Volkswagen").exploded = true;
    }
}

Migrating Scatter series

With Qt Charts:

ChartView {
    ScatterSeries {
        XYPoint { x: 1.5; y: 1.5 }
        XYPoint { x: 1.5; y: 1.6 }
        XYPoint { x: 1.57; y: 1.55 }
        XYPoint { x: 1.8; y: 1.8 }
        XYPoint { x: 1.9; y: 1.6 }
        XYPoint { x: 2.1; y: 1.3 }
        XYPoint { x: 2.5; y: 2.1 }
    }
}

With Qt Graphs:

GraphsView {
    // Graphs don't calculate a visible range for axes.
    // You should define the visible range explicitly.
    ValueAxis {
        id: xyAxis
        min: 1.3
        max: 2.5
    }
    axisX: xyAxis
    axisY: xyAxis

    ScatterSeries {
        XYPoint { x: 1.5; y: 1.5 }
        XYPoint { x: 1.5; y: 1.6 }
        XYPoint { x: 1.57; y: 1.55 }
        XYPoint { x: 1.8; y: 1.8 }
        XYPoint { x: 1.9; y: 1.6 }
        XYPoint { x: 2.1; y: 1.3 }
        XYPoint { x: 2.5; y: 2.1 }
    }
}

Migrating Spline series

With Qt Charts:

ChartView {
    SplineSeries {
        name: "Spline"
        XYPoint { x: 0; y: 0.0 }
        XYPoint { x: 1.1; y: 3.2 }
        XYPoint { x: 1.9; y: 2.4 }
        XYPoint { x: 2.1; y: 2.1 }
        XYPoint { x: 2.9; y: 2.6 }
        XYPoint { x: 3.4; y: 2.3 }
        XYPoint { x: 4.1; y: 3.1 }
    }
}

With Qt Graphs:

GraphsView {
    ValueAxis {
        id: xyAxis
        max: 5
    }
    axisX: xyAxis
    axisY: xyAxis
    SplineSeries {
        XYPoint { x: 0; y: 0.0 }
        XYPoint { x: 1.1; y: 3.2 }
        XYPoint { x: 1.9; y: 2.4 }
        XYPoint { x: 2.1; y: 2.1 }
        XYPoint { x: 2.9; y: 2.6 }
        XYPoint { x: 3.4; y: 2.3 }
        XYPoint { x: 4.1; y: 3.1 }
    }
}
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