SlideArea.cs

using Gtk;
using SkiaSharp;
using SkiaSharp.Views.Desktop;
using SkiaSharp.Views.Gtk;
using System;
 
namespace BioGTK
{
    public class SlideArea : SKDrawingArea
    {
        #region Events
 
        public event Action<SKCanvas, int, int> OnSkiaRender;
 
        #endregion
 
        #region Fields
 
        private SKSlideRenderer _renderer;
        private bool _isInitialized;
 
        #endregion
 
        #region Constructor
 
        public SlideArea() : base()
        {
            // Configure widget
            this.Expand = true;
            this.CanFocus = true;
 
            // Subscribe to paint event
            this.PaintSurface += OnPaintSurface;
 
            _isInitialized = true;
        }
 
        #endregion
 
        #region Renderer Integration
 
        public void SetRenderer(SKSlideRenderer renderer)
        {
            _renderer = renderer;
        }
 
        #endregion
 
        #region Rendering
 
        private void OnPaintSurface(object sender, SKPaintSurfaceEventArgs e)
        {
            if (!_isInitialized)
                return;
 
            var canvas = e.Surface.Canvas;
            var width = e.Info.Width;
            var height = e.Info.Height;
 
            // Clear canvas
            canvas.Clear(SKColors.Black);
 
            try
            {
                // Render slide content from renderer
                if (_renderer != null)
                {
                    _renderer.DrawToCanvas(canvas, width, height);
                }
 
                // Allow custom drawing on top (annotations, etc.)
                OnSkiaRender?.Invoke(canvas, width, height);
            }
            catch (Exception ex)
            {
                Console.WriteLine($"Paint surface error: {ex.Message}");
            }
        }
 
        public void RequestRedraw()
        {
            this.QueueDraw();
 
            if (this.IsRealized && this.Window != null)
            {
                this.Window.InvalidateRect(this.Allocation, false);
                this.Window.ProcessUpdates(true);
            }
        }
 
        #endregion
 
        #region Cleanup
 
        protected override void Dispose(bool disposing)
        {
            if (disposing)
            {
                this.PaintSurface -= OnPaintSurface;
            }
 
            base.Dispose(disposing);
        }
 
        #endregion
    }
}