// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.IO;
using System.Net.Http;
using System.Threading;
using System.Threading.Tasks;
using System.Timers;
using Microsoft.Maui.Controls;
using Microsoft.Maui.Graphics;
using SkiaSharp;
using Svg.Skia;
namespace Microsoft.Maui.Platform;
///
/// Skia-rendered image control with SVG support and GIF animation.
/// Full MAUI-compliant implementation.
///
public class SkiaImage : SkiaView
{
#region Image Cache
///
/// Static image cache for decoded bitmaps to avoid re-decoding.
/// Key is the file path or URI, value is the cached bitmap data.
///
private static readonly ConcurrentDictionary _imageCache = new();
private static readonly object _cacheLock = new();
private const int MaxCacheSize = 50; // Maximum number of cached images
private const long MaxCacheMemoryBytes = 100 * 1024 * 1024; // 100MB max cache
private class CachedImage
{
public SKBitmap? Bitmap { get; set; }
public List? Frames { get; set; }
public bool IsAnimated { get; set; }
public DateTime LastAccessed { get; set; }
public long MemorySize { get; set; }
}
///
/// Clears the image cache.
///
public static void ClearCache()
{
lock (_cacheLock)
{
foreach (var cached in _imageCache.Values)
{
cached.Bitmap?.Dispose();
if (cached.Frames != null)
{
foreach (var frame in cached.Frames)
{
frame.Bitmap?.Dispose();
}
}
}
_imageCache.Clear();
}
}
private static void TrimCacheIfNeeded()
{
lock (_cacheLock)
{
if (_imageCache.Count <= MaxCacheSize)
return;
// Calculate total memory
long totalMemory = 0;
foreach (var cached in _imageCache.Values)
{
totalMemory += cached.MemorySize;
}
// If under memory limit and count limit, don't trim
if (totalMemory < MaxCacheMemoryBytes && _imageCache.Count <= MaxCacheSize)
return;
// Remove oldest entries until under limits
var sortedEntries = _imageCache.ToArray();
Array.Sort(sortedEntries, (a, b) => a.Value.LastAccessed.CompareTo(b.Value.LastAccessed));
int removeCount = Math.Max(1, _imageCache.Count - MaxCacheSize + 10);
for (int i = 0; i < removeCount && i < sortedEntries.Length; i++)
{
if (_imageCache.TryRemove(sortedEntries[i].Key, out var removed))
{
removed.Bitmap?.Dispose();
if (removed.Frames != null)
{
foreach (var frame in removed.Frames)
{
frame.Bitmap?.Dispose();
}
}
}
}
}
}
#endregion
#region Animation Support
private class AnimationFrame
{
public SKBitmap? Bitmap { get; set; }
public int Duration { get; set; } // Duration in milliseconds
}
private List? _animationFrames;
private int _currentFrameIndex;
private System.Timers.Timer? _animationTimer;
private bool _isAnimatedImage;
#endregion
#region BindableProperties
///
/// Bindable property for Aspect.
///
public static readonly BindableProperty AspectProperty =
BindableProperty.Create(
nameof(Aspect),
typeof(Aspect),
typeof(SkiaImage),
Aspect.AspectFit,
BindingMode.TwoWay,
propertyChanged: (b, o, n) => ((SkiaImage)b).Invalidate());
///
/// Bindable property for IsOpaque.
///
public static readonly BindableProperty IsOpaqueProperty =
BindableProperty.Create(
nameof(IsOpaque),
typeof(bool),
typeof(SkiaImage),
false,
BindingMode.TwoWay,
propertyChanged: (b, o, n) => ((SkiaImage)b).Invalidate());
///
/// Bindable property for IsAnimationPlaying.
///
public static readonly BindableProperty IsAnimationPlayingProperty =
BindableProperty.Create(
nameof(IsAnimationPlaying),
typeof(bool),
typeof(SkiaImage),
false,
BindingMode.TwoWay,
propertyChanged: (b, o, n) => ((SkiaImage)b).OnIsAnimationPlayingChanged((bool)n));
///
/// Bindable property for ImageBackgroundColor (MAUI Color for background).
///
public static readonly BindableProperty ImageBackgroundColorProperty =
BindableProperty.Create(
nameof(ImageBackgroundColor),
typeof(Color),
typeof(SkiaImage),
Colors.Transparent,
BindingMode.TwoWay,
propertyChanged: (b, o, n) => ((SkiaImage)b).Invalidate());
#endregion
#region Color Conversion Helper
///
/// Converts a MAUI Color to SkiaSharp SKColor.
/// Uses the ToSKColor() extension from ColorExtensions for MAUI-compliant theming.
///
private static SKColor ToSKColor(Color color)
{
if (color == null) return SKColors.Transparent;
return color.ToSKColor();
}
#endregion
private SKBitmap? _bitmap;
private SKImage? _image;
private bool _isLoading;
private string? _currentFilePath;
private string? _cacheKey;
private bool _isSvg;
private CancellationTokenSource? _loadCts;
private readonly object _loadLock = new object();
private double _svgLoadedWidth;
private double _svgLoadedHeight;
private bool _pendingSvgReload;
private SKRect _lastArrangedBounds;
public SKBitmap? Bitmap
{
get => _bitmap;
set
{
// Don't dispose if this is a cached bitmap
if (_bitmap != null && (_cacheKey == null || !_imageCache.ContainsKey(_cacheKey)))
{
_bitmap.Dispose();
}
_bitmap = value;
_image?.Dispose();
_image = value != null ? SKImage.FromBitmap(value) : null;
Invalidate();
}
}
///
/// Gets or sets the aspect ratio scaling mode.
///
public Aspect Aspect
{
get => (Aspect)GetValue(AspectProperty);
set => SetValue(AspectProperty, value);
}
///
/// Gets or sets whether the image is opaque.
///
public bool IsOpaque
{
get => (bool)GetValue(IsOpaqueProperty);
set => SetValue(IsOpaqueProperty, value);
}
///
/// Gets whether the image is currently loading.
///
public bool IsLoading => _isLoading;
///
/// Gets or sets whether animation is playing (for GIF support).
/// When set to true, animated GIFs will play their animation.
/// When set to false, the first frame is displayed.
///
public bool IsAnimationPlaying
{
get => (bool)GetValue(IsAnimationPlayingProperty);
set => SetValue(IsAnimationPlayingProperty, value);
}
///
/// Gets or sets the image background color (MAUI Color type).
///
public Color ImageBackgroundColor
{
get => (Color)GetValue(ImageBackgroundColorProperty);
set => SetValue(ImageBackgroundColorProperty, value);
}
public new double WidthRequest
{
get => base.WidthRequest;
set
{
base.WidthRequest = value;
ScheduleSvgReloadIfNeeded();
}
}
public new double HeightRequest
{
get => base.HeightRequest;
set
{
base.HeightRequest = value;
ScheduleSvgReloadIfNeeded();
}
}
public event EventHandler? ImageLoaded;
public event EventHandler? ImageLoadingError;
private void OnIsAnimationPlayingChanged(bool isPlaying)
{
if (_isAnimatedImage && _animationFrames != null && _animationFrames.Count > 1)
{
if (isPlaying)
{
StartAnimation();
}
else
{
StopAnimation();
}
}
}
private void StartAnimation()
{
if (_animationFrames == null || _animationFrames.Count <= 1)
return;
StopAnimation();
var frame = _animationFrames[_currentFrameIndex];
int duration = frame.Duration > 0 ? frame.Duration : 100; // Default 100ms if not specified
_animationTimer = new System.Timers.Timer(duration);
_animationTimer.Elapsed += OnAnimationTimerElapsed;
_animationTimer.AutoReset = false;
_animationTimer.Start();
}
private void StopAnimation()
{
if (_animationTimer != null)
{
_animationTimer.Stop();
_animationTimer.Elapsed -= OnAnimationTimerElapsed;
_animationTimer.Dispose();
_animationTimer = null;
}
}
private void OnAnimationTimerElapsed(object? sender, ElapsedEventArgs e)
{
if (_animationFrames == null || _animationFrames.Count <= 1 || !IsAnimationPlaying)
return;
// Move to next frame
_currentFrameIndex = (_currentFrameIndex + 1) % _animationFrames.Count;
// Update the displayed image
var frame = _animationFrames[_currentFrameIndex];
if (frame.Bitmap != null)
{
_image?.Dispose();
_image = SKImage.FromBitmap(frame.Bitmap);
Invalidate();
}
// Schedule next frame
if (IsAnimationPlaying)
{
int duration = frame.Duration > 0 ? frame.Duration : 100;
_animationTimer?.Stop();
if (_animationTimer != null)
{
_animationTimer.Interval = duration;
_animationTimer.Start();
}
}
}
private void ScheduleSvgReloadIfNeeded()
{
if (_isSvg && !string.IsNullOrEmpty(_currentFilePath))
{
double widthRequest = WidthRequest;
double heightRequest = HeightRequest;
if (widthRequest > 0.0 && heightRequest > 0.0 &&
(Math.Abs(_svgLoadedWidth - widthRequest) > 0.5 || Math.Abs(_svgLoadedHeight - heightRequest) > 0.5) &&
!_pendingSvgReload)
{
_pendingSvgReload = true;
_ = ReloadSvgDebounced();
}
}
}
private async Task ReloadSvgDebounced()
{
await Task.Delay(10);
_pendingSvgReload = false;
if (!string.IsNullOrEmpty(_currentFilePath) && WidthRequest > 0.0 && HeightRequest > 0.0)
{
await LoadSvgAtSizeAsync(_currentFilePath, WidthRequest, HeightRequest);
}
}
protected override void OnDraw(SKCanvas canvas, SKRect bounds)
{
// Draw background if not opaque
var bgColor = ImageBackgroundColor != null ? ToSKColor(ImageBackgroundColor) : SKColors.Transparent;
if (!IsOpaque && bgColor != SKColors.Transparent)
{
using var bgPaint = new SKPaint
{
Color = bgColor,
Style = SKPaintStyle.Fill
};
canvas.DrawRect(bounds, bgPaint);
}
if (_image == null)
return;
int width = _image.Width;
int height = _image.Height;
if (width <= 0 || height <= 0)
return;
SKRect destRect = CalculateDestRect(bounds, width, height);
using var paint = new SKPaint
{
IsAntialias = true,
FilterQuality = SKFilterQuality.High
};
canvas.DrawImage(_image, destRect, paint);
}
private SKRect CalculateDestRect(SKRect bounds, float imageWidth, float imageHeight)
{
switch (Aspect)
{
case Aspect.Fill:
return bounds;
case Aspect.AspectFit:
{
float scale = Math.Min(bounds.Width / imageWidth, bounds.Height / imageHeight);
float destWidth = imageWidth * scale;
float destHeight = imageHeight * scale;
float destX = bounds.Left + (bounds.Width - destWidth) / 2f;
float destY = bounds.Top + (bounds.Height - destHeight) / 2f;
return new SKRect(destX, destY, destX + destWidth, destY + destHeight);
}
case Aspect.AspectFill:
{
float scale = Math.Max(bounds.Width / imageWidth, bounds.Height / imageHeight);
float destWidth = imageWidth * scale;
float destHeight = imageHeight * scale;
float destX = bounds.Left + (bounds.Width - destWidth) / 2f;
float destY = bounds.Top + (bounds.Height - destHeight) / 2f;
return new SKRect(destX, destY, destX + destWidth, destY + destHeight);
}
case Aspect.Center:
{
float destX = bounds.Left + (bounds.Width - imageWidth) / 2f;
float destY = bounds.Top + (bounds.Height - imageHeight) / 2f;
return new SKRect(destX, destY, destX + imageWidth, destY + imageHeight);
}
default:
return bounds;
}
}
public async Task LoadFromFileAsync(string filePath)
{
_isLoading = true;
Invalidate();
try
{
List searchPaths = new List
{
filePath,
Path.Combine(AppContext.BaseDirectory, filePath),
Path.Combine(AppContext.BaseDirectory, "Resources", "Images", filePath),
Path.Combine(AppContext.BaseDirectory, "Resources", filePath)
};
// Also try SVG if looking for PNG
if (filePath.EndsWith(".png", StringComparison.OrdinalIgnoreCase))
{
string svgPath = Path.ChangeExtension(filePath, ".svg");
searchPaths.Add(svgPath);
searchPaths.Add(Path.Combine(AppContext.BaseDirectory, svgPath));
searchPaths.Add(Path.Combine(AppContext.BaseDirectory, "Resources", "Images", svgPath));
searchPaths.Add(Path.Combine(AppContext.BaseDirectory, "Resources", svgPath));
}
string? foundPath = null;
foreach (string path in searchPaths)
{
if (File.Exists(path))
{
foundPath = path;
break;
}
}
if (foundPath == null)
{
_isLoading = false;
_isSvg = false;
_currentFilePath = null;
_cacheKey = null;
ImageLoadingError?.Invoke(this, new ImageLoadingErrorEventArgs(new FileNotFoundException(filePath)));
return;
}
_isSvg = foundPath.EndsWith(".svg", StringComparison.OrdinalIgnoreCase);
_currentFilePath = foundPath;
_cacheKey = foundPath;
// Check cache first
if (_imageCache.TryGetValue(foundPath, out var cached))
{
cached.LastAccessed = DateTime.UtcNow;
if (cached.IsAnimated && cached.Frames != null)
{
_isAnimatedImage = true;
_animationFrames = cached.Frames;
_currentFrameIndex = 0;
if (cached.Frames.Count > 0 && cached.Frames[0].Bitmap != null)
{
_image?.Dispose();
_image = SKImage.FromBitmap(cached.Frames[0].Bitmap);
}
if (IsAnimationPlaying)
{
StartAnimation();
}
}
else if (cached.Bitmap != null)
{
_isAnimatedImage = false;
_bitmap = cached.Bitmap;
_image?.Dispose();
_image = SKImage.FromBitmap(cached.Bitmap);
}
_isLoading = false;
ImageLoaded?.Invoke(this, EventArgs.Empty);
Invalidate();
return;
}
if (_isSvg)
{
await LoadSvgAtSizeAsync(foundPath, WidthRequest, HeightRequest);
}
else
{
await LoadImageWithAnimationSupportAsync(foundPath);
}
_isLoading = false;
ImageLoaded?.Invoke(this, EventArgs.Empty);
}
catch (Exception ex)
{
_isLoading = false;
ImageLoadingError?.Invoke(this, new ImageLoadingErrorEventArgs(ex));
}
Invalidate();
}
private async Task LoadImageWithAnimationSupportAsync(string filePath)
{
await Task.Run(() =>
{
using var stream = File.OpenRead(filePath);
using var codec = SKCodec.Create(stream);
if (codec == null)
{
// Fallback to simple decode
stream.Position = 0;
var bitmap = SKBitmap.Decode(stream);
if (bitmap != null)
{
CacheAndSetBitmap(filePath, bitmap, false);
}
return;
}
int frameCount = codec.FrameCount;
if (frameCount > 1)
{
// Animated image (GIF)
_isAnimatedImage = true;
_animationFrames = new List();
var info = codec.Info;
for (int i = 0; i < frameCount; i++)
{
var frameInfo = codec.FrameInfo[i];
var bitmap = new SKBitmap(info.Width, info.Height);
var options = new SKCodecOptions(i);
codec.GetPixels(bitmap.Info, bitmap.GetPixels(), options);
_animationFrames.Add(new AnimationFrame
{
Bitmap = bitmap,
Duration = frameInfo.Duration > 0 ? frameInfo.Duration : 100
});
}
// Cache the animation frames
long memorySize = _animationFrames.Sum(f => (long)(f.Bitmap?.ByteCount ?? 0));
_imageCache[filePath] = new CachedImage
{
Frames = _animationFrames,
IsAnimated = true,
LastAccessed = DateTime.UtcNow,
MemorySize = memorySize
};
TrimCacheIfNeeded();
// Set first frame as current image
_currentFrameIndex = 0;
if (_animationFrames.Count > 0 && _animationFrames[0].Bitmap != null)
{
_image?.Dispose();
_image = SKImage.FromBitmap(_animationFrames[0].Bitmap);
}
// Start animation if requested
if (IsAnimationPlaying)
{
StartAnimation();
}
}
else
{
// Static image
_isAnimatedImage = false;
var bitmap = SKBitmap.Decode(codec, codec.Info);
if (bitmap != null)
{
CacheAndSetBitmap(filePath, bitmap, false);
}
}
});
}
private void CacheAndSetBitmap(string cacheKey, SKBitmap bitmap, bool isAnimated)
{
_imageCache[cacheKey] = new CachedImage
{
Bitmap = bitmap,
IsAnimated = isAnimated,
LastAccessed = DateTime.UtcNow,
MemorySize = bitmap.ByteCount
};
TrimCacheIfNeeded();
_bitmap = bitmap;
_image?.Dispose();
_image = SKImage.FromBitmap(bitmap);
}
private async Task LoadSvgAtSizeAsync(string svgPath, double targetWidth, double targetHeight)
{
_loadCts?.Cancel();
CancellationTokenSource cts = new CancellationTokenSource();
_loadCts = cts;
try
{
SKBitmap? newBitmap = null;
await Task.Run(() =>
{
if (cts.Token.IsCancellationRequested)
return;
using var svg = new SKSvg();
svg.Load(svgPath);
if (svg.Picture != null && !cts.Token.IsCancellationRequested)
{
SKRect cullRect = svg.Picture.CullRect;
float requestedWidth = (targetWidth > 0.0)
? (float)targetWidth
: ((cullRect.Width <= 24f) ? 24f : cullRect.Width);
float requestedHeight = (targetHeight > 0.0)
? (float)targetHeight
: ((cullRect.Height <= 24f) ? 24f : cullRect.Height);
float scale = Math.Min(requestedWidth / cullRect.Width, requestedHeight / cullRect.Height);
int bitmapWidth = Math.Max(1, (int)(cullRect.Width * scale));
int bitmapHeight = Math.Max(1, (int)(cullRect.Height * scale));
newBitmap = new SKBitmap(bitmapWidth, bitmapHeight, false);
using var canvas = new SKCanvas(newBitmap);
canvas.Clear(SKColors.Transparent);
canvas.Scale(scale);
// Translate to handle negative viewBox coordinates (e.g., Material icons use 0 -960 960 960)
canvas.Translate(-cullRect.Left, -cullRect.Top);
canvas.DrawPicture(svg.Picture, null);
}
}, cts.Token);
if (!cts.Token.IsCancellationRequested && newBitmap != null)
{
_svgLoadedWidth = (targetWidth > 0.0) ? targetWidth : newBitmap.Width;
_svgLoadedHeight = (targetHeight > 0.0) ? targetHeight : newBitmap.Height;
_isAnimatedImage = false;
Bitmap = newBitmap;
}
else
{
newBitmap?.Dispose();
}
}
catch (OperationCanceledException)
{
// Cancellation is expected when reloading SVG at different sizes
}
}
public async Task LoadFromStreamAsync(Stream stream)
{
_isLoading = true;
_cacheKey = null; // Streams are not cached by default
Invalidate();
try
{
await Task.Run(() =>
{
using var codec = SKCodec.Create(stream);
if (codec == null)
{
stream.Position = 0;
var bitmap = SKBitmap.Decode(stream);
if (bitmap != null)
{
_isAnimatedImage = false;
Bitmap = bitmap;
}
return;
}
int frameCount = codec.FrameCount;
if (frameCount > 1)
{
// Animated image
_isAnimatedImage = true;
_animationFrames = new List();
var info = codec.Info;
for (int i = 0; i < frameCount; i++)
{
var frameInfo = codec.FrameInfo[i];
var bitmap = new SKBitmap(info.Width, info.Height);
var options = new SKCodecOptions(i);
codec.GetPixels(bitmap.Info, bitmap.GetPixels(), options);
_animationFrames.Add(new AnimationFrame
{
Bitmap = bitmap,
Duration = frameInfo.Duration > 0 ? frameInfo.Duration : 100
});
}
_currentFrameIndex = 0;
if (_animationFrames.Count > 0 && _animationFrames[0].Bitmap != null)
{
_image?.Dispose();
_image = SKImage.FromBitmap(_animationFrames[0].Bitmap);
}
if (IsAnimationPlaying)
{
StartAnimation();
}
}
else
{
_isAnimatedImage = false;
var bitmap = SKBitmap.Decode(codec, codec.Info);
if (bitmap != null)
{
Bitmap = bitmap;
}
}
});
_isLoading = false;
ImageLoaded?.Invoke(this, EventArgs.Empty);
}
catch (Exception ex)
{
_isLoading = false;
ImageLoadingError?.Invoke(this, new ImageLoadingErrorEventArgs(ex));
}
Invalidate();
}
public async Task LoadFromUriAsync(Uri uri)
{
_isLoading = true;
_cacheKey = uri.ToString();
Invalidate();
try
{
// Check cache first
if (_imageCache.TryGetValue(_cacheKey, out var cached))
{
cached.LastAccessed = DateTime.UtcNow;
if (cached.IsAnimated && cached.Frames != null)
{
_isAnimatedImage = true;
_animationFrames = cached.Frames;
_currentFrameIndex = 0;
if (cached.Frames.Count > 0 && cached.Frames[0].Bitmap != null)
{
_image?.Dispose();
_image = SKImage.FromBitmap(cached.Frames[0].Bitmap);
}
if (IsAnimationPlaying)
{
StartAnimation();
}
}
else if (cached.Bitmap != null)
{
_isAnimatedImage = false;
_bitmap = cached.Bitmap;
_image?.Dispose();
_image = SKImage.FromBitmap(cached.Bitmap);
}
_isLoading = false;
ImageLoaded?.Invoke(this, EventArgs.Empty);
Invalidate();
return;
}
using HttpClient httpClient = new HttpClient();
var data = await httpClient.GetByteArrayAsync(uri);
using var stream = new MemoryStream(data);
await Task.Run(() =>
{
using var codec = SKCodec.Create(stream);
if (codec == null)
{
stream.Position = 0;
var bitmap = SKBitmap.Decode(stream);
if (bitmap != null)
{
_isAnimatedImage = false;
CacheAndSetBitmap(_cacheKey, bitmap, false);
}
return;
}
int frameCount = codec.FrameCount;
if (frameCount > 1)
{
// Animated image
_isAnimatedImage = true;
_animationFrames = new List();
var info = codec.Info;
for (int i = 0; i < frameCount; i++)
{
var frameInfo = codec.FrameInfo[i];
var bitmap = new SKBitmap(info.Width, info.Height);
var options = new SKCodecOptions(i);
codec.GetPixels(bitmap.Info, bitmap.GetPixels(), options);
_animationFrames.Add(new AnimationFrame
{
Bitmap = bitmap,
Duration = frameInfo.Duration > 0 ? frameInfo.Duration : 100
});
}
// Cache the animation frames
long memorySize = _animationFrames.Sum(f => (long)(f.Bitmap?.ByteCount ?? 0));
_imageCache[_cacheKey] = new CachedImage
{
Frames = _animationFrames,
IsAnimated = true,
LastAccessed = DateTime.UtcNow,
MemorySize = memorySize
};
TrimCacheIfNeeded();
_currentFrameIndex = 0;
if (_animationFrames.Count > 0 && _animationFrames[0].Bitmap != null)
{
_image?.Dispose();
_image = SKImage.FromBitmap(_animationFrames[0].Bitmap);
}
if (IsAnimationPlaying)
{
StartAnimation();
}
}
else
{
_isAnimatedImage = false;
var bitmap = SKBitmap.Decode(codec, codec.Info);
if (bitmap != null)
{
CacheAndSetBitmap(_cacheKey, bitmap, false);
}
}
});
_isLoading = false;
ImageLoaded?.Invoke(this, EventArgs.Empty);
}
catch (Exception ex)
{
_isLoading = false;
ImageLoadingError?.Invoke(this, new ImageLoadingErrorEventArgs(ex));
}
Invalidate();
}
public void LoadFromData(byte[] data)
{
try
{
_cacheKey = null;
using var stream = new MemoryStream(data);
using var codec = SKCodec.Create(stream);
if (codec == null)
{
stream.Position = 0;
var bitmap = SKBitmap.Decode(stream);
if (bitmap != null)
{
_isAnimatedImage = false;
Bitmap = bitmap;
}
ImageLoaded?.Invoke(this, EventArgs.Empty);
return;
}
int frameCount = codec.FrameCount;
if (frameCount > 1)
{
// Animated image
_isAnimatedImage = true;
_animationFrames = new List();
var info = codec.Info;
for (int i = 0; i < frameCount; i++)
{
var frameInfo = codec.FrameInfo[i];
var bitmap = new SKBitmap(info.Width, info.Height);
var options = new SKCodecOptions(i);
codec.GetPixels(bitmap.Info, bitmap.GetPixels(), options);
_animationFrames.Add(new AnimationFrame
{
Bitmap = bitmap,
Duration = frameInfo.Duration > 0 ? frameInfo.Duration : 100
});
}
_currentFrameIndex = 0;
if (_animationFrames.Count > 0 && _animationFrames[0].Bitmap != null)
{
_image?.Dispose();
_image = SKImage.FromBitmap(_animationFrames[0].Bitmap);
}
if (IsAnimationPlaying)
{
StartAnimation();
}
}
else
{
_isAnimatedImage = false;
var bitmap = SKBitmap.Decode(codec, codec.Info);
if (bitmap != null)
{
Bitmap = bitmap;
}
}
ImageLoaded?.Invoke(this, EventArgs.Empty);
}
catch (Exception ex)
{
ImageLoadingError?.Invoke(this, new ImageLoadingErrorEventArgs(ex));
}
}
///
/// Loads the image from an SKBitmap.
///
public void LoadFromBitmap(SKBitmap bitmap)
{
try
{
_isSvg = false;
_currentFilePath = null;
_cacheKey = null;
_isAnimatedImage = false;
StopAnimation();
_animationFrames = null;
Bitmap = bitmap;
_isLoading = false;
ImageLoaded?.Invoke(this, EventArgs.Empty);
}
catch (Exception ex)
{
_isLoading = false;
ImageLoadingError?.Invoke(this, new ImageLoadingErrorEventArgs(ex));
}
Invalidate();
}
public override void Arrange(Rect bounds)
{
base.Arrange(bounds);
// If no explicit size requested and this is an SVG, check if we need to reload at larger size
if (!(base.WidthRequest > 0.0) || !(base.HeightRequest > 0.0))
{
if (_isSvg && !string.IsNullOrEmpty(_currentFilePath) && !_isLoading)
{
float width = (float)bounds.Width;
float height = (float)bounds.Height;
if ((width > _svgLoadedWidth * 1.1 || height > _svgLoadedHeight * 1.1) &&
width > 0f && height > 0f &&
(width != _lastArrangedBounds.Width || height != _lastArrangedBounds.Height))
{
_lastArrangedBounds = new SKRect((float)bounds.Left, (float)bounds.Top, (float)bounds.Right, (float)bounds.Bottom);
_ = LoadSvgAtSizeAsync(_currentFilePath, width, height);
}
}
}
}
protected override Rect ArrangeOverride(Rect bounds)
{
var desiredWidth = DesiredSize.Width;
var desiredHeight = DesiredSize.Height;
if (desiredWidth > 0 && desiredHeight > 0 &&
(desiredWidth < bounds.Width || desiredHeight < bounds.Height))
{
double finalWidth = Math.Min(desiredWidth, bounds.Width);
double finalHeight = Math.Min(desiredHeight, bounds.Height);
double x = bounds.Left;
var hAlignValue = (int)HorizontalOptions.Alignment;
if (hAlignValue == 1) x = bounds.Left + (bounds.Width - finalWidth) / 2;
else if (hAlignValue == 2) x = bounds.Right - finalWidth;
double y = bounds.Top;
var vAlignValue = (int)VerticalOptions.Alignment;
if (vAlignValue == 1) y = bounds.Top + (bounds.Height - finalHeight) / 2;
else if (vAlignValue == 2) y = bounds.Bottom - finalHeight;
return new Rect(x, y, finalWidth, finalHeight);
}
return bounds;
}
protected override Size MeasureOverride(Size availableSize)
{
double widthRequest = base.WidthRequest;
double heightRequest = base.HeightRequest;
if (widthRequest > 0.0 && heightRequest > 0.0)
return new Size(widthRequest, heightRequest);
if (_image == null)
{
if (widthRequest > 0.0) return new Size(widthRequest, widthRequest);
if (heightRequest > 0.0) return new Size(heightRequest, heightRequest);
return new Size(100.0, 100.0);
}
float imageWidth = _image.Width;
float imageHeight = _image.Height;
if (widthRequest > 0.0)
{
double scale = widthRequest / imageWidth;
return new Size(widthRequest, imageHeight * scale);
}
if (heightRequest > 0.0)
{
double scale = heightRequest / imageHeight;
return new Size(imageWidth * scale, heightRequest);
}
if (availableSize.Width < double.MaxValue && availableSize.Height < double.MaxValue)
{
double scale = Math.Min(availableSize.Width / imageWidth, availableSize.Height / imageHeight);
return new Size(imageWidth * scale, imageHeight * scale);
}
if (availableSize.Width < double.MaxValue)
{
double scale = availableSize.Width / imageWidth;
return new Size(availableSize.Width, imageHeight * scale);
}
if (availableSize.Height < double.MaxValue)
{
double scale = availableSize.Height / imageHeight;
return new Size(imageWidth * scale, availableSize.Height);
}
return new Size(imageWidth, imageHeight);
}
protected override void Dispose(bool disposing)
{
if (disposing)
{
StopAnimation();
// Only dispose if not cached
if (_cacheKey == null || !_imageCache.ContainsKey(_cacheKey))
{
_bitmap?.Dispose();
if (_animationFrames != null)
{
foreach (var frame in _animationFrames)
{
frame.Bitmap?.Dispose();
}
}
}
_image?.Dispose();
}
base.Dispose(disposing);
}
}
///
/// Event args for image loading errors.
///
public class ImageLoadingErrorEventArgs : EventArgs
{
public Exception Exception { get; }
public ImageLoadingErrorEventArgs(Exception exception)
{
Exception = exception;
}
}