public override void DrawInContext(CoreGraphics.CGContext ctx)
{
base.DrawInContext(ctx);
var knobFrame = CGRect.Inflate(PaintFrame, -2.0f, -2.0f);
UIBezierPath knobPath = UIBezierPath.FromRoundedRect((CGRect)knobFrame, (nfloat)knobFrame.Height * Slider.Curvaceousness / 2.0f);
// 1) fill - with a subtle shadow
ctx.SetShadow(new CGSize(0, 1), 1.0f, UIColor.Gray.CGColor);
ctx.SetFillColor(Slider.KnobColor.CGColor);
ctx.AddPath(knobPath.CGPath);
ctx.FillPath();
// 2) outline
ctx.SetStrokeColor(UIColor.Gray.CGColor);
ctx.SetLineWidth((nfloat)0.5f);
ctx.AddPath(knobPath.CGPath);
ctx.StrokePath();
// 3) inner gradient
var rect = CGRect.Inflate(knobFrame, -2.0f, -2.0f);
var clipPath = UIBezierPath.FromRoundedRect((CGRect)rect, (nfloat)rect.Height * Slider.Curvaceousness / 2.0f);
CGGradient myGradient;
CGColorSpace myColorspace;
nfloat[] locations = { 0.0f, 1.0f };
nfloat[] components = { 0.0f, 0.0f, 0.0f, 0.15f, // Start color
0.0f, 0.0f, 0.0f, 0.05f }; // End color
myColorspace = CGColorSpace.CreateDeviceRGB(); // CGColorSpaceCreateDeviceRGB();
myGradient = new CGGradient(myColorspace, components, locations);
CGPoint startPoint = new CGPoint((float)rect.GetMidX(), (float)rect.GetMinY());
CGPoint endPoint = new CGPoint((float)rect.GetMidX(), (float)rect.GetMaxY());
ctx.SaveState();
ctx.AddPath(clipPath.CGPath);
ctx.Clip();
ctx.DrawLinearGradient((CGGradient)myGradient, (CGPoint)startPoint, (CGPoint)endPoint, (CGGradientDrawingOptions)0);
myGradient.Dispose();
myColorspace.Dispose();
ctx.RestoreState();
// 4) highlight
if (Highlighted)
{
// fill
ctx.SetFillColor(UIColor.FromWhiteAlpha((nfloat)0.0f, (nfloat)0.1f).CGColor);
ctx.AddPath(knobPath.CGPath);
ctx.FillPath();
}
}
void UpdateIOSContext(Font font, Brush brush, Pen pen)
{
if (font != null)
{
context.SetFontSize(font.Size);
}
if (brush != null)
{
context.SetFillColor(ToCGColor(((SolidBrush)brush).Color));
context.SetFillColor(ToCGColor(((SolidBrush)brush).Color));
}
if (pen != null)
{
context.SetStrokeColor(ToCGColor(pen.Color));
context.SetLineWidth(pen.Width);
}
}
