using ElmSharp;
using EColor = ElmSharp.Color;
namespace Xamarin.Forms.Platform.Tizen
{
public class FrameRenderer : ViewRenderer
{
const int _thickness = 2;
const int _shadow_shift = 2;
const int _shadow_thickness = _thickness + 2;
static readonly EColor s_DefaultColor = EColor.Black;
static readonly EColor s_ShadowColor = EColor.FromRgba(80, 80, 80, 50);
Polygon _shadow = null;
Polygon _frame = null;
public FrameRenderer()
{
RegisterPropertyHandler(Frame.OutlineColorProperty, UpdateColor);
RegisterPropertyHandler(Frame.HasShadowProperty, UpdateShadowVisibility);
}
protected override void OnElementChanged(ElementChangedEventArgs e)
{
if (Control == null)
{
SetNativeControl(new Native.Canvas(Forms.Context.MainWindow));
_shadow = new Polygon(NativeView);
_shadow.Color = s_ShadowColor;
Control.Children.Add(_shadow);
_frame = new Polygon(NativeView);
_frame.Show();
Control.Children.Add(_frame);
Control.LayoutUpdated += OnLayoutUpdated;
}
base.OnElementChanged(e);
}
protected override void Dispose(bool disposing)
{
if (disposing)
{
if (Control != null)
{
Control.LayoutUpdated -= OnLayoutUpdated;
}
}
base.Dispose(disposing);
}
static void DrawFrame(Polygon frame, int left, int top, int right, int bottom, int thickness)
{
frame.ClearPoints();
if (left + thickness >= right || top + thickness >= bottom)
{
if (left >= right || top >= bottom)
return;
// shape reduces to a rectangle
frame.AddPoint(left, top);
frame.AddPoint(right, top);
frame.AddPoint(right, bottom);
frame.AddPoint(left, bottom);
return;
}
// outside edge
frame.AddPoint(left, top);
frame.AddPoint(right, top);
frame.AddPoint(right, bottom);
frame.AddPoint(left, bottom);
frame.AddPoint(left, top + thickness);
// and inside edge
frame.AddPoint(left + thickness, top + thickness);
frame.AddPoint(left + thickness, bottom - thickness);
frame.AddPoint(right - thickness, bottom - thickness);
frame.AddPoint(right - thickness, top + thickness);
frame.AddPoint(left, top + thickness);
}
void OnLayoutUpdated(object sender, Native.LayoutEventArgs e)
{
UpdateGeometry();
}
void UpdateGeometry()
{
var geometry = NativeView.Geometry;
DrawFrame(_frame,
geometry.X,
geometry.Y,
geometry.Right,
geometry.Bottom,
_thickness
);
DrawFrame(_shadow,
geometry.X + _shadow_shift,
geometry.Y + _shadow_shift,
geometry.Right - _thickness + _shadow_shift + _shadow_thickness,
geometry.Bottom - _thickness + _shadow_shift + _shadow_thickness,
_shadow_thickness
);
}
void UpdateColor()
{
if (Element.OutlineColor.IsDefault)
_frame.Color = s_DefaultColor;
else
_frame.Color = Element.OutlineColor.ToNative();
}
void UpdateShadowVisibility()
{
if (Element.HasShadow)
_shadow.Show();
else
_shadow.Hide();
}
}
}