Angular Gauge

sample image

View model

using System.Collections.Generic;
using LiveChartsCore;
using CommunityToolkit.Mvvm.ComponentModel;
using LiveChartsCore.SkiaSharpView;
using LiveChartsCore.SkiaSharpView.Extensions;
using LiveChartsCore.VisualElements;
using LiveChartsCore.SkiaSharpView.Drawing;
using LiveChartsCore.SkiaSharpView.VisualElements;
using LiveChartsCore.Defaults;
using CommunityToolkit.Mvvm.Input;
using System;

namespace ViewModelsSamples.Pies.AngularGauge;

public partial class ViewModel : ObservableObject
{
    private readonly Random _random = new();

    public ViewModel()
    {
        var sectionsOuter = 130;
        var sectionsWidth = 20;

        Needle = new NeedleVisual
        {
            Value = 45
        };

        Series = GaugeGenerator.BuildAngularGaugeSections(
            new GaugeItem(60, s => SetStyle(sectionsOuter, sectionsWidth, s)),
            new GaugeItem(30, s => SetStyle(sectionsOuter, sectionsWidth, s)),
            new GaugeItem(10, s => SetStyle(sectionsOuter, sectionsWidth, s)));

        VisualElements = new VisualElement<SkiaSharpDrawingContext>[]
        {
            new AngularTicksVisual
            {
                LabelsSize = 16,
                LabelsOuterOffset = 15,
                OuterOffset = 65,
                TicksLength = 20
            },
            Needle
        };
    }

    public IEnumerable<ISeries> Series { get; set; }

    public IEnumerable<VisualElement<SkiaSharpDrawingContext>> VisualElements { get; set; }

    public NeedleVisual Needle { get; set; }

    [RelayCommand]
    public void DoRandomChange()
    {
        // modifying the Value property updates and animates the chart automatically
        Needle.Value = _random.Next(0, 100);
    }

    private static void SetStyle(
        double sectionsOuter, double sectionsWidth, PieSeries<ObservableValue> series)
    {
        series.OuterRadiusOffset = sectionsOuter;
        series.MaxRadialColumnWidth = sectionsWidth;
    }
}

HTML

@page "/Pies/AngularGauge"
@using LiveChartsCore.SkiaSharpView.Blazor
@using ViewModelsSamples.Pies.AngularGauge

<style>
	.sample-wrap {
		display: inline-block;
		width: 600px;
		height: 600px;
	}
</style>

<button class="btn btn-primary" @onclick="ViewModel.DoRandomChange">
	Update Value
</button>

<div class="sample-wrap">
	<PieChart
		Series="ViewModel.Series"
        VisualElements="ViewModel.VisualElements"
		InitialRotation="-225"
        MaxAngle="270"
        MinValue="0"
        MaxValue="100">
	</PieChart>
</div>

@code {
	public ViewModel ViewModel { get; set; } = new();
}

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Pie chart control
pie series properties
Gauges