50 lines
1.5 KiB
C#
50 lines
1.5 KiB
C#
using System;
|
|
|
|
namespace Ooui
|
|
{
|
|
public class Canvas : Element
|
|
{
|
|
CanvasRenderingContext2D context2d = new CanvasRenderingContext2D ();
|
|
int gotContext2d = 0;
|
|
|
|
int width = 300;
|
|
public int Width {
|
|
get => width;
|
|
set => SetProperty (ref width, value <= 0 ? 150 : value, "width");
|
|
}
|
|
|
|
int height = 150;
|
|
public int Height {
|
|
get => height;
|
|
set => SetProperty (ref height, value <= 0 ? 150 : value, "height");
|
|
}
|
|
|
|
public Canvas ()
|
|
: base ("canvas")
|
|
{
|
|
context2d.MessageSent += Send;
|
|
}
|
|
|
|
public CanvasRenderingContext2D GetContext2D ()
|
|
{
|
|
if (System.Threading.Interlocked.CompareExchange (ref gotContext2d, 1, 0) == 0) {
|
|
var mcall = Message.Call (Id, "getContext", "2d");
|
|
mcall.ResultId = context2d.Id;
|
|
Send (mcall);
|
|
}
|
|
return context2d;
|
|
}
|
|
protected override bool SaveStateMessageIfNeeded (Message message)
|
|
{
|
|
if (message.TargetId == Id) {
|
|
switch (message.MessageType) {
|
|
case MessageType.Call when message.Key == "getContext" && message.Value is Array a && a.Length == 1 && "2d".Equals (a.GetValue (0)):
|
|
AddStateMessage (message);
|
|
break;
|
|
}
|
|
}
|
|
return base.SaveStateMessageIfNeeded (message);
|
|
}
|
|
}
|
|
}
|