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-rw-r--r--Xamarin.Forms.Platform.Tizen/Native/Image.cs124
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diff --git a/Xamarin.Forms.Platform.Tizen/Native/Image.cs b/Xamarin.Forms.Platform.Tizen/Native/Image.cs
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+using System.Threading.Tasks;
+using ElmSharp;
+using EImage = ElmSharp.Image;
+using ESize = ElmSharp.Size;
+
+namespace Xamarin.Forms.Platform.Tizen.Native
+{
+ /// <summary>
+ /// Extends the ElmSharp.Image class with functionality useful to renderer.
+ /// </summary>
+ public class Image : EImage, IMeasurable
+ {
+ Aspect _aspect;
+
+ /// <summary>
+ /// Initializes a new instance of the <see cref="Xamarin.Forms.Platform.Tizen.Native.Image"/> class.
+ /// </summary>
+ /// <param name="parent">The parent EvasObject.</param>
+ public Image(EvasObject parent) : base(parent)
+ {
+ IsScaling = true;
+ CanScaleUp = true;
+ CanScaleDown = true;
+
+ ApplyAspect(Aspect.AspectFit);
+ }
+
+ /// <summary>
+ /// Gets or sets the image aspect ratio preserving option.
+ /// </summary>
+ /// <value>The aspect option.</value>
+ public Aspect Aspect
+ {
+ get
+ {
+ return _aspect;
+ }
+
+ set
+ {
+ if (_aspect != value)
+ {
+ ApplyAspect(value);
+ }
+ }
+ }
+
+ /// <summary>
+ /// Loads image data from the given <see cref="Xamarin.Forms.ImageSource"/> asynchronously.
+ /// </summary>
+ /// <returns>A task which will be completed when image data is loaded.</returns>
+ /// <param name="source">Image source specifying from where the image data has to be loaded.</param>
+ public Task<bool> LoadFromImageSourceAsync(ImageSource source)
+ {
+ IImageSourceHandler handler;
+ if (source != null && (handler = Registrar.Registered.GetHandler<IImageSourceHandler>(source.GetType())) != null)
+ {
+ return handler.LoadImageAsync(this, source);
+ }
+ return Task.FromResult<bool>(false);
+ }
+
+ /// <summary>
+ /// Implements the <see cref="Xamarin.Forms.Platform.Tizen.Native.IMeasurable"/> interface.
+ /// </summary>
+ /// <param name="availableWidth">Available width.</param>
+ /// <param name="availableHeight">Available height.</param>
+ public ESize Measure(int availableWidth, int availableHeight)
+ {
+ var imageSize = ObjectSize;
+
+ var size = new ESize()
+ {
+ Width = imageSize.Width,
+ Height = imageSize.Height,
+ };
+
+ if (0 != availableWidth && 0 != availableHeight
+ && (imageSize.Width > availableWidth || imageSize.Height > availableHeight))
+ {
+ // when available size is limited and insufficient for the image ...
+ double imageRatio = (double)imageSize.Width / (double)imageSize.Height;
+ double availableRatio = (double)availableWidth / (double)availableHeight;
+ // depending on the relation between availableRatio and imageRatio, copy the availableWidth or availableHeight
+ // and calculate the size which preserves the image ratio, but does not exceed the available size
+ size.Width = availableRatio > imageRatio ? imageSize.Width * availableHeight / imageSize.Height : availableWidth;
+ size.Height = availableRatio > imageRatio ? availableHeight : imageSize.Height * availableWidth / imageSize.Width;
+ }
+
+ return size;
+ }
+
+ /// <summary>
+ /// Sets the <c>IsFixedAspect</c> and <c>CanFillOutside</c> properties according to the given <paramref name="aspect"/>.
+ /// </summary>
+ /// <param name="aspect">The aspect setting to be applied to the image.</param>
+ void ApplyAspect(Aspect aspect)
+ {
+ _aspect = aspect;
+
+ switch (_aspect)
+ {
+ case Aspect.AspectFit:
+ IsFixedAspect = true;
+ CanFillOutside = false;
+ break;
+
+ case Aspect.AspectFill:
+ IsFixedAspect = true;
+ CanFillOutside = true;
+ break;
+
+ case Aspect.Fill:
+ IsFixedAspect = false;
+ CanFillOutside = false;
+ break;
+
+ default:
+ Log.Warn("Invalid Aspect value: {0}", _aspect);
+ break;
+ }
+ }
+ }
+}