Ooui-tws-port/Ooui.Forms/Renderers/LabelRenderer.cs

180 lines
6.7 KiB
C#

using System;
using System.ComponentModel;
using System.Diagnostics;
using Ooui.Forms.Extensions;
using Xamarin.Forms;
using NativeLabel = Ooui.Span;
namespace Ooui.Forms.Renderers
{
public class LabelRenderer : ViewRenderer<Xamarin.Forms.Label, NativeLabel>
{
SizeRequest _perfectSize;
bool _perfectSizeValid;
public override SizeRequest GetDesiredSize (double widthConstraint, double heightConstraint)
{
// System.Console.WriteLine($"Label.GetDesiredSize ({widthConstraint}, {heightConstraint})");
if (!_perfectSizeValid) {
var size = Element.Text.MeasureSize (Element.FontFamily, Element.FontSize, Element.FontAttributes, double.PositiveInfinity, double.PositiveInfinity);
size.Width = Math.Ceiling (size.Width);
size.Height = Math.Ceiling (size.Height);
_perfectSize = new SizeRequest (size, new Size (Element.FontSize, Element.FontSize));
_perfectSizeValid = true;
}
var widthFits = widthConstraint >= _perfectSize.Request.Width;
var heightFits = heightConstraint >= _perfectSize.Request.Height;
if (widthFits && heightFits)
return _perfectSize;
var resultRequestSize = Element.Text.MeasureSize (Element.FontFamily, Element.FontSize, Element.FontAttributes, widthConstraint, heightConstraint);
var result = new SizeRequest (resultRequestSize, resultRequestSize);
var tinyWidth = Math.Min (10, result.Request.Width);
result.Minimum = new Size (tinyWidth, result.Request.Height);
if (widthFits || Element.LineBreakMode == LineBreakMode.NoWrap)
return result;
bool containerIsNotInfinitelyWide = !double.IsInfinity (widthConstraint);
if (containerIsNotInfinitelyWide) {
bool textCouldHaveWrapped = Element.LineBreakMode == LineBreakMode.WordWrap || Element.LineBreakMode == LineBreakMode.CharacterWrap;
bool textExceedsContainer = result.Request.Width > widthConstraint;
if (textExceedsContainer || textCouldHaveWrapped) {
var expandedWidth = Math.Max (tinyWidth, widthConstraint);
result.Request = new Size (expandedWidth, result.Request.Height);
}
}
return result;
}
protected override void OnElementChanged (ElementChangedEventArgs<Xamarin.Forms.Label> e)
{
if (e.NewElement != null) {
if (Control == null) {
SetNativeControl (new NativeLabel ());
}
UpdateText ();
UpdateTextColor ();
UpdateFont ();
UpdateLineBreakMode ();
UpdateAlignment ();
}
base.OnElementChanged (e);
}
protected override void OnElementPropertyChanged (object sender, PropertyChangedEventArgs e)
{
base.OnElementPropertyChanged (sender, e);
if (Control == null)
return;
if (e.PropertyName == Xamarin.Forms.Label.HorizontalTextAlignmentProperty.PropertyName)
UpdateAlignment ();
else if (e.PropertyName == Xamarin.Forms.Label.VerticalTextAlignmentProperty.PropertyName)
UpdateAlignment ();
else if (e.PropertyName == Xamarin.Forms.Label.TextColorProperty.PropertyName)
UpdateTextColor ();
else if (e.PropertyName == Xamarin.Forms.Label.FontProperty.PropertyName)
UpdateFont ();
else if (e.PropertyName == Xamarin.Forms.Label.TextProperty.PropertyName)
UpdateText ();
else if (e.PropertyName == Xamarin.Forms.Label.FormattedTextProperty.PropertyName)
UpdateText ();
else if (e.PropertyName == Xamarin.Forms.Label.LineBreakModeProperty.PropertyName)
UpdateLineBreakMode ();
}
protected override void SetBackgroundColor (Xamarin.Forms.Color color)
{
Style.BackgroundColor = color.ToOouiColor (Colors.Clear);
}
void UpdateAlignment ()
{
this.Style.Display = "table";
Control.Style.Display = "table-cell";
this.Style.TextAlign = Element.HorizontalTextAlignment.ToOouiTextAlign ();
Control.Style.VerticalAlign = Element.VerticalTextAlignment.ToOouiVerticalAlign ();
}
void UpdateLineBreakMode ()
{
_perfectSizeValid = false;
//switch (Element.LineBreakMode)
//{
// case LineBreakMode.NoWrap:
// Control.LineBreakMode = UILineBreakMode.Clip;
// Control.Lines = 1;
// break;
// case LineBreakMode.WordWrap:
// Control.LineBreakMode = UILineBreakMode.WordWrap;
// Control.Lines = 0;
// break;
// case LineBreakMode.CharacterWrap:
// Control.LineBreakMode = UILineBreakMode.CharacterWrap;
// Control.Lines = 0;
// break;
// case LineBreakMode.HeadTruncation:
// Control.LineBreakMode = UILineBreakMode.HeadTruncation;
// Control.Lines = 1;
// break;
// case LineBreakMode.MiddleTruncation:
// Control.LineBreakMode = UILineBreakMode.MiddleTruncation;
// Control.Lines = 1;
// break;
// case LineBreakMode.TailTruncation:
// Control.LineBreakMode = UILineBreakMode.TailTruncation;
// Control.Lines = 1;
// break;
//}
}
bool isTextFormatted;
void UpdateText ()
{
_perfectSizeValid = false;
if (Element.FormattedText != null) {
Control.Text = Element.Text;
isTextFormatted = true;
}
else {
Control.Text = Element.Text;
isTextFormatted = false;
}
}
void UpdateFont ()
{
if (isTextFormatted)
return;
_perfectSizeValid = false;
Element.SetStyleFont (Element.FontFamily, Element.FontSize, Element.FontAttributes, Control.Style);
}
void UpdateTextColor ()
{
if (isTextFormatted)
return;
_perfectSizeValid = false;
var textColor = (Xamarin.Forms.Color)Element.GetValue (Xamarin.Forms.Label.TextColorProperty);
Control.Style.Color = textColor.ToOouiColor(Xamarin.Forms.Color.Black);
}
}
}