LanMountainDesktop/LanMontainDesktop/Views/Components/ClockWidget.axaml.cs

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

namespace LanMontainDesktop.Views.Components;

public partial class ClockWidget : UserControl
{
    private readonly DispatcherTimer _timer = new()
    {
        Interval = TimeSpan.FromSeconds(1)
    };

    public ClockWidget()
    {
        InitializeComponent();

        _timer.Tick += OnTimerTick;
        AttachedToVisualTree += OnAttachedToVisualTree;
        DetachedFromVisualTree += OnDetachedFromVisualTree;
        UpdateClock();
    }

    private void OnAttachedToVisualTree(object? sender, VisualTreeAttachmentEventArgs e)
    {
        UpdateClock();
        _timer.Start();
    }

    private void OnDetachedFromVisualTree(object? sender, VisualTreeAttachmentEventArgs e)
    {
        _timer.Stop();
    }

    private void OnTimerTick(object? sender, EventArgs e)
    {
        UpdateClock();
    }

    private void UpdateClock()
    {
        var now = DateTime.Now;
        TimeTextBlock.Text = now.ToString("HH:mm:ss", CultureInfo.CurrentCulture);
    }
}