YZWater3/src/YZWater.Avalonia/Controls/FanControl.cs

using Avalonia;
using Avalonia.Controls;
using Avalonia.Media;
using Avalonia.Threading;
using System;
using System.Globalization;

namespace YZWater.Avalonia.Controls;

public class FanControl : Control
{
    public static readonly StyledProperty<bool> IsRunningProperty =
        AvaloniaProperty.Register<FanControl, bool>(nameof(IsRunning), false);
    public static readonly StyledProperty<double> SpeedProperty =
        AvaloniaProperty.Register<FanControl, double>(nameof(Speed), 1.0);
    public static readonly StyledProperty<string> TextProperty =
        AvaloniaProperty.Register<FanControl, string>(nameof(Text), "风扇");

    public bool IsRunning { get => GetValue(IsRunningProperty); set => SetValue(IsRunningProperty, value); }
    public double Speed { get => GetValue(SpeedProperty); set => SetValue(SpeedProperty, value); }
    public string Text { get => GetValue(TextProperty); set => SetValue(TextProperty, value); }

    private double _angle;
    private IDisposable? _timer;

    static FanControl() { AffectsRender<FanControl>(IsRunningProperty, SpeedProperty, TextProperty); }
    protected override void OnAttachedToVisualTree(VisualTreeAttachmentEventArgs e) { base.OnAttachedToVisualTree(e); if (IsRunning) StartAnim(); }
    protected override void OnDetachedFromVisualTree(VisualTreeAttachmentEventArgs e) { base.OnDetachedFromVisualTree(e); StopAnim(); }
    protected override void OnPropertyChanged(AvaloniaPropertyChangedEventArgs change)
    {
        base.OnPropertyChanged(change);
        if (change.Property == IsRunningProperty) { if (IsRunning) StartAnim(); else { StopAnim(); _angle = 0; } }
    }
    private void StartAnim() { StopAnim(); _timer = DispatcherTimer.Run(() => { _angle += Speed * 2; if (_angle >= 360) _angle -= 360; InvalidateVisual(); return true; }, TimeSpan.FromMilliseconds(50)); }
    private void StopAnim() { _timer?.Dispose(); _timer = null; }

    public override void Render(DrawingContext context)
    {
        base.Render(context);
        var bounds = new Rect(Bounds.Size);
        var cx = bounds.Width / 2; var cy = bounds.Height / 2;
        var radius = Math.Min(bounds.Width, bounds.Height) / 2 - 5;
        var typeface = new Typeface("Microsoft YaHei", FontStyle.Normal, FontWeight.Bold);
        var fanColor = IsRunning ? ThemeHelper.Success() : ThemeHelper.TextDisabled();

        // 外框
        context.DrawRectangle(null, new Pen(ThemeHelper.Border(), 2), new Rect(cx - radius, cy - radius, radius * 2, radius * 2));

        // 叶片
        var bladeCount = 4;
        var bladeLen = radius * 0.8;
        var bladeW = radius * 0.25;
        for (int i = 0; i < bladeCount; i++)
        {
            var angle = _angle + (360.0 / bladeCount) * i;
            var bx = cx + Math.Cos(angle * Math.PI / 180) * bladeLen * 0.4;
            var by = cy + Math.Sin(angle * Math.PI / 180) * bladeLen * 0.4;
            context.DrawRectangle(fanColor, null, new Rect(bx - bladeW / 2, by - bladeLen / 2, bladeW, bladeLen));
        }

        // 中心
        var cr = radius * 0.15;
        context.DrawEllipse(fanColor, null, new Rect(cx - cr, cy - cr, cr * 2, cr * 2));

        // 文字
        if (!string.IsNullOrEmpty(Text))
        {
            var t = new FormattedText(Text, CultureInfo.CurrentCulture, FlowDirection.LeftToRight, typeface, 10, ThemeHelper.TextPrimary());
            context.DrawText(t, new Point(cx - t.Width / 2, bounds.Bottom - t.Height - 2));
        }
    }

    protected override Size MeasureOverride(Size availableSize) => new Size(50, 50);
}