protected override void OnMeasure(int widthMeasureSpec, int heightMeasureSpec)
{
base.OnMeasure(widthMeasureSpec, heightMeasureSpec);
var availableSize = ViewHelper.LogicalSizeFromSpec(widthMeasureSpec, heightMeasureSpec);
var measuredSize = _layouter.Measure(availableSize);
if (
!double.IsInfinity(availableSize.Width) &&
!double.IsInfinity(availableSize.Height)
)
{
measuredSize = this.AdjustSize(availableSize, measuredSize);
}
var physicalMeasuredSize = measuredSize
.LogicalToPhysicalPixels();
// Report our final dimensions.
var width = (int)physicalMeasuredSize.Width;
var height = (int)physicalMeasuredSize.Height;
SetMeasuredDimension(width, height);
IFrameworkElementHelper
.SizeThatFits(this, new Size(width, height).PhysicalToLogicalPixels());
}
public override CGSize SizeThatFits(CGSize size)
{
size = IFrameworkElementHelper.SizeThatFits(this, size);
size = _layouter.Measure(size.ToFoundationSize());
return(size);
}
public override CGSize SizeThatFits(CGSize size)
{
var hasSameDesiredSize =
!_measureInvalidated &&
_previousAvailableSize != null &&
_previousDesiredSize.Width == size.Width &&
_previousDesiredSize.Height == size.Height;
var isSingleLineNarrower =
!_measureInvalidated &&
_previousAvailableSize != null &&
_previousDesiredSize.Width <= size.Width &&
_previousDesiredSize.Height == size.Height;
if (hasSameDesiredSize || isSingleLineNarrower)
{
return(_previousDesiredSize);
}
else
{
_previousAvailableSize = size;
_measureInvalidated = false;
UpdateTypography();
var horizontalPadding = Padding.Left + Padding.Right;
var verticalPadding = Padding.Top + Padding.Bottom;
// available size considering min/max width/height
// necessary, because the height of a wrapping TextBlock depends on its width
size = IFrameworkElementHelper.SizeThatFits(this, size);
// available size considering padding
size.Width -= (nfloat)horizontalPadding;
size.Height -= (nfloat)verticalPadding;
var result = base.SizeThatFits(size);
if (result.Height == 0) // this can happen when Text is null or empty
{
// This measures the height correctly, even if the Text is null or empty
// This matches Windows where empty TextBlocks still have a height (especially useful when measuring ListView items with no DataContext)
result = (Text ?? NSString.Empty).StringSize(this.Font, size);
}
if (AdjustsFontSizeToFitWidth && !nfloat.IsNaN(size.Width))
{
result.Width = size.Width;
}
result.Width += (nfloat)horizontalPadding;
result.Height += (nfloat)verticalPadding;
result = IFrameworkElementHelper.SizeThatFits(this, result);
return(_previousDesiredSize = new CGSize(Math.Ceiling(result.Width), Math.Ceiling(result.Height)));
}
}
private Size GetConstrainedSize(Size availableSize)
{
var constrainedSize = IFrameworkElementHelper.SizeThatFits(_element as IFrameworkElement, availableSize);
#if XAMARIN_IOS
return(constrainedSize.ToFoundationSize());
#else
return(constrainedSize);
#endif
}
public override CGSize SizeThatFits(CGSize size)
{
size = IFrameworkElementHelper.SizeThatFits(this, size);
if (nfloat.IsPositiveInfinity(size.Height) || nfloat.IsPositiveInfinity(size.Width))
{
// Changes from IOS 9 doc.
// See following
// https://jira.appcelerator.org/browse/TIMOB-19203
// https://developer.apple.com/library/prerelease/ios/releasenotes/General/RN-iOSSDK-9.0/
size = base.SizeThatFits(size);
}
return(size);
}
public override CGSize SizeThatFits(CGSize size)
{
var textBox = _textBox.GetTarget();
if (textBox != null)
{
//bug in base.SizeThatFits(size) where we get stuck and size is never return for value NaN
if (nfloat.IsNaN(size.Width))
{
size = new CGSize(nfloat.PositiveInfinity, nfloat.PositiveInfinity);
}
//at this point size returned represent all the space available
//to have the same behavior of Windows, we need to call UIView.SizeThatFits() to return a size that best fits
var expectedSize = base.SizeThatFits(size);
//Disable the scroll if you are given enough space. Else framework will use the scrollview to move text up
ScrollEnabled = expectedSize.Height >= size.Height;
var canTakeAllSpace = expectedSize.Height < size.Height && !nfloat.IsInfinity(size.Height) && size.Height != textBox.MaxHeight;
// if textBox.Height is set, size.Height will be the same
var shouldTakeAllSpace = !double.IsNaN(textBox.Height) || textBox.VerticalAlignment == VerticalAlignment.Stretch;
if (canTakeAllSpace && shouldTakeAllSpace)
{
expectedSize.Height = size.Height; //Take all the space given
}
canTakeAllSpace = expectedSize.Width < size.Width && !nfloat.IsInfinity(size.Width) && size.Width != textBox.MaxWidth;
// if textBox.Width is set, size.Width will be the same
shouldTakeAllSpace = !double.IsNaN(textBox.Width) || textBox.HorizontalAlignment == HorizontalAlignment.Stretch;
if (canTakeAllSpace && shouldTakeAllSpace)
{
expectedSize.Width = size.Width; //Take all the space given
}
var result = IFrameworkElementHelper.SizeThatFits(this, expectedSize); //Adjust for NaN and MaxHeight..
return(result);
}
else
{
return(CGSize.Empty);
}
}
protected override Size MeasureOverride(Size availableSize)
{
var sizeThatFits = IFrameworkElementHelper.SizeThatFits(Panel, availableSize);
double maxChildWidth = 0f, maxChildHeight = 0f;
//Per the link, if the NativePagedView has no fixed size in a dimension, wrap it to the size of its largest child. - http://stackoverflow.com/questions/8394681/android-i-am-unable-to-have-viewpager-wrap-content
//This might be brittle if items have varying dimensions along the unfixed axis; one (hackish) solution would be to increase OffscreenPageLimit (the number of offscreen pages that are kept).
if (double.IsPositiveInfinity(sizeThatFits.Width) || double.IsPositiveInfinity(sizeThatFits.Height))
{
foreach (var child in this.GetChildren())
{
var desiredChildSize = MeasureChild(child, sizeThatFits);
maxChildWidth = Math.Max(maxChildWidth, desiredChildSize.Width);
maxChildHeight = Math.Max(maxChildHeight, desiredChildSize.Height);
}
}
return(new Size(
!double.IsPositiveInfinity(sizeThatFits.Width) ? sizeThatFits.Width : maxChildWidth,
!double.IsPositiveInfinity(sizeThatFits.Height) ? sizeThatFits.Height : maxChildHeight
));
}
public override CGSize SizeThatFits(CGSize size)
{
size = IFrameworkElementHelper.SizeThatFits(this, size);
if (nfloat.IsPositiveInfinity(size.Height) || nfloat.IsPositiveInfinity(size.Width))
{
// Changes from IOS 9 doc.
// See following
// https://jira.appcelerator.org/browse/TIMOB-19203
// https://developer.apple.com/library/prerelease/ios/releasenotes/General/RN-iOSSDK-9.0/
size = base.SizeThatFits(size);
}
if (this.Frame.Size != size)
{
this.SetDimensions(size.Width, size.Height);
// forces PickerModel.GetComponentWidth to get called,
// which then receives the new dimensions (which might differ from the default value of 320)
this.SetNeedsLayout();
}
return(size);
}
public override CGSize SizeThatFits(CGSize size)
{
return(IFrameworkElementHelper.SizeThatFits(this, base.SizeThatFits(size)));
}
public override CGSize SizeThatFits(CGSize size)
{
size = base.SizeThatFits(size);
size = IFrameworkElementHelper.SizeThatFits(this, size);
return(size);
}