protected override Size ArrangeOverride(Size finalSize)
{
if (this.Log().IsEnabled(Microsoft.Extensions.Logging.LogLevel.Debug))
{
this.Log().Debug(Panel.ToString() + $" arranging with finalSize={finalSize}");
}
//If we are given a non-zero size to draw into, set the target dimensions to load the image with accordingly
ImageControl.SetTargetImageSize(finalSize);
if (this.Log().IsEnabled(LogLevel.Warning))
{
if (ImageControl._openedImage != null)
{
var renderedSize = finalSize.LogicalToPhysicalPixels();
var loadedSize = ImageControl.SourceImageSize.LogicalToPhysicalPixels();
if (((renderedSize.Width + 512) < loadedSize.Width ||
(renderedSize.Height + 512) < loadedSize.Height) && ImageControl.Source.UseTargetSize)
{
this.Log().Warn("The image was opened with a size of {0} and is displayed using a size of only {1}. Try optimizing the image size by using a smaller source or not using Stretch.Uniform or using fixed Width and Height."
.InvariantCultureFormat(loadedSize, renderedSize));
}
}
}
return(finalSize);
}
protected override Size MeasureOverride(Size availableSize)
{
if (this.Log().IsEnabled(Microsoft.Extensions.Logging.LogLevel.Debug))
{
this.Log().Debug(Panel.ToString() + $" measuring with availableSize={availableSize}");
}
ImageControl.SetTargetImageSize(availableSize);
var size = InnerMeasureOverride(availableSize);
return(size);
}
protected override Size MeasureOverride(Size availableSize)
{
Size sourceSize = ImageControl.SourceImageSize;
var hasKnownWidth = ImageControl.HasKnownWidth(availableSize.Width);
var hasKnownHeight = ImageControl.HasKnownHeight(availableSize.Height);
ImageControl._hasFiniteBounds = hasKnownWidth && hasKnownHeight;
// If one dimension is known and the other isn't, we need to consider uniformity based on the dimension we know.
// Example: Horizontal=Stretch, Vertical=Top, Stretch=Uniform, SourceWidth=200, SourceHeight=100 (AspectRatio=2)
// This Image is Inside a StackPanel (infinite height and width=300).
// When being measured, the height can be calculated using the aspect ratio of the source image and the available width.
// That means the Measure should return
// height = (KnownWidth=300) / (AspectRatio=2) = 150
// ...and not height = (SourceHeight=100) = 100
if (hasKnownWidth ^ hasKnownHeight)
{
var aspectRatio = sourceSize.Width / sourceSize.Height;
var desiredSize = new Size();
if (hasKnownWidth)
{
var knownWidth = ImageControl.GetKnownWidth(availableSize.Width, sourceSize.Width);
desiredSize.Width = knownWidth;
switch (ImageControl.Stretch)
{
case Stretch.Uniform:
// If sourceSize is empty, aspect ratio is undefined so we return 0.
// Since apsect ratio can have a lot of decimal, iOS ceils Image size to 0.5 if it's not a precise size (like 111.111111111)
// so the desiredSize will never match the actual size causing an infinite measuring and can freeze the app
desiredSize.Height = sourceSize == default(Size) ? 0 : Math.Ceiling((knownWidth / aspectRatio) * 2) / 2;
break;
case Stretch.None:
desiredSize.Height = sourceSize.Height;
break;
case Stretch.Fill:
case Stretch.UniformToFill:
desiredSize.Height = double.IsInfinity(availableSize.Height) ? sourceSize.Height : availableSize.Height;
break;
}
if (this.Log().IsEnabled(Microsoft.Extensions.Logging.LogLevel.Debug))
{
this.Log().Debug(Panel.ToString() + $" measuring with knownWidth={knownWidth} with availableSize={availableSize}, returning desiredSize={desiredSize}");
}
return(desiredSize);
}
else if (hasKnownHeight)
{
var knownHeight = ImageControl.GetKnownHeight(availableSize.Height, sourceSize.Height);
desiredSize.Height = knownHeight;
switch (ImageControl.Stretch)
{
case Stretch.Uniform:
//If sourceSize is empty, aspect ratio is undefined so we return 0
// Since apsect ratio can have a lot of decimal, iOS ceils Image size to 0.5 if it's not a precise size (like 111.111111111)
// so the desiredSize will never match the actual size causing an infinite measuring and can freeze the app
desiredSize.Width = sourceSize == default(Size) ? 0 : Math.Ceiling(knownHeight * aspectRatio * 2) / 2;
break;
case Stretch.None:
desiredSize.Width = sourceSize.Width;
break;
case Stretch.Fill:
case Stretch.UniformToFill:
desiredSize.Width = double.IsInfinity(availableSize.Width) ? sourceSize.Width : availableSize.Width;
break;
}
if (this.Log().IsEnabled(Microsoft.Extensions.Logging.LogLevel.Debug))
{
this.Log().Debug(Panel.ToString() + $" measuring with knownHeight={knownHeight} with availableSize={availableSize}, returning desiredSize={desiredSize}");
}
return(desiredSize);
}
}
if (sourceSize.Width > availableSize.Width || sourceSize.Height > availableSize.Height || (hasKnownWidth && hasKnownHeight))
{
var knownWidth = ImageControl.GetKnownWidth(availableSize.Width, sourceSize.Width);
var knownHeight = ImageControl.GetKnownHeight(availableSize.Height, sourceSize.Height);
var knownSize = new Size(knownWidth, knownHeight);
switch (ImageControl.Stretch)
{
case Stretch.Uniform:
var desiredSize = new Size();
var aspectRatio = sourceSize.Width / sourceSize.Height;
// Since apsect ratio can have a lot of decimal, iOS ceils Image size to 0.5 if it's not a precise size (like 111.111111111)
// so the desiredSize will never match the actual size causing an infinite measuring and can freeze the app
desiredSize.Width = Math.Min(knownWidth, Math.Ceiling(knownHeight * aspectRatio * 2) / 2);
desiredSize.Height = Math.Min(knownHeight, Math.Ceiling(knownWidth / aspectRatio * 2) / 2);
if (this.Log().IsEnabled(Microsoft.Extensions.Logging.LogLevel.Debug))
{
this.Log().Debug(Panel.ToString() + $" measuring with knownSize={knownSize} and Stretch.Uniform with availableSize={availableSize}, returning desiredSize={desiredSize}");
}
return(desiredSize);
//TODO: #11103 - For futur needs, for an Image with no specified size, need to implement Stretching: UniformToFill, Fill, None
//case Stretch.UniformToFill:
//case Stretch.Fill:
//case Stretch.None:
//return sourceSize;
}
}
if (this.Log().IsEnabled(Microsoft.Extensions.Logging.LogLevel.Debug))
{
this.Log().Debug(Panel.ToString() + $" measuring with availableSize={availableSize}, returning sourceSize={sourceSize}");
}
return(sourceSize);
}