signals

Gum.Signal/Core/SignalCenter.cs

@@ -0,0 +1,92 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+
+namespace Gum.Signal.Core
+{
+	public class SignalCenter
+	{
+		private readonly object _lock = new object();
+
+		private readonly List<Entry> _entries = new List<Entry>();
+
+		public void Subscribe<T>(Action<T> action)
+		{
+			lock (_lock)
+			{
+				_entries.Add(new Entry(action, typeof(T)));
+			}
+		}
+
+		public void Unsubscribe<T>(Action<T> action)
+		{
+			lock (_lock)
+			{
+				Entry[] entriesToRemove = _entries.Where(e => (Action<T>)e.Delegate == action).ToArray();
+				for (int index = 0; index < entriesToRemove.Length; index++)
+				{
+					_entries.Remove(entriesToRemove[index]);
+				}
+			}
+		}
+
+		public void Fire<T>(T signal)
+		{
+			Type type = typeof(T);
+			lock (_lock)
+			{
+				for (int index = 0; index < _entries.Count; index++)
+				{
+					if (_entries[index].Type == type)
+					{
+						((Action<T>)_entries[index].Delegate).Invoke(signal);
+					}
+				}	
+			}
+		}
+
+		public bool Exists<T>(Action<T> action)
+		{
+			lock (_lock)
+			{
+				for (int index = 0; index < _entries.Count; index++)
+				{
+					if (_entries[index].Delegate.Equals(action))
+					{
+						return true;
+					}
+				}	
+			}
+
+			return false;
+		}
+
+		private readonly struct Entry : IEquatable<Entry>
+		{
+			public readonly Delegate Delegate;
+
+			public readonly Type Type;
+
+			public Entry(Delegate @delegate, Type type)
+			{
+				Delegate = @delegate;
+				Type = type;
+			}
+
+			public bool Equals(Entry other)
+			{
+				return Equals(Delegate, other.Delegate) && Type == other.Type;
+			}
+
+			public override bool Equals(object obj)
+			{
+				return obj is Entry other && Equals(other);
+			}
+
+			public override int GetHashCode()
+			{
+				return HashCode.Combine(Delegate, Type);
+			}
+		}
+	}
+}

Gum.Signal/Gum.Signal.csproj

@@ -0,0 +1,11 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+    <PropertyGroup>
+        <TargetFramework>netstandard2.1</TargetFramework>
+    </PropertyGroup>
+
+    <ItemGroup>
+      <ProjectReference Include="..\Gum.Core\Gum.Core.csproj" />
+    </ItemGroup>
+
+</Project>

Gum.sln

@@ -12,6 +12,8 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Gum.Sandbox", "Gum.Sandbox\
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Gum.Composer", "Gum.Composer\Gum.Composer.csproj", "{D9F81A6C-D0DD-4289-9D7D-515E4B7A7AFC}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Gum.Signal", "Gum.Signal\Gum.Signal.csproj", "{6DA54680-9E54-4E6D-A1EC-961C816B56D5}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -42,5 +44,9 @@ Global
 		{D9F81A6C-D0DD-4289-9D7D-515E4B7A7AFC}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{D9F81A6C-D0DD-4289-9D7D-515E4B7A7AFC}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{D9F81A6C-D0DD-4289-9D7D-515E4B7A7AFC}.Release|Any CPU.Build.0 = Release|Any CPU
+		{6DA54680-9E54-4E6D-A1EC-961C816B56D5}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{6DA54680-9E54-4E6D-A1EC-961C816B56D5}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{6DA54680-9E54-4E6D-A1EC-961C816B56D5}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{6DA54680-9E54-4E6D-A1EC-961C816B56D5}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 EndGlobal

Tests/DataStructureTests/Foo.cs

@@ -0,0 +1,6 @@
+namespace Tests.DataStructureTests
+{
+	public class Foo
+	{
+	}
+}

Tests/PoolingTests/WeakStackTests.cs → Tests/DataStructureTests/WeakStackTests.cs

@@ -1,13 +1,13 @@
 using Gum.Core.DataStructures;
 using NUnit.Framework;
 
-namespace Tests.PoolingTests
+namespace Tests.DataStructureTests
 {
     [TestFixture]
     public class WeakStackTests
     {
         [Test]
-        public void WeakStack_Push()
+        public void Push()
         {
             WeakStack<Foo> weakStack = new WeakStack<Foo>();
 
@@ -20,7 +20,7 @@ public void WeakStack_Push()
         }
 
         [Test]
-        public void WeakStack_Pop()
+        public void Pop()
         {
             WeakStack<Foo> weakStack = new WeakStack<Foo>();
 

Tests/SignalTests/MockSignals.cs

@@ -0,0 +1,12 @@
+namespace Tests.SignalTests
+{
+	public readonly struct FooSignal
+	{
+		public readonly int Value;
+
+		public FooSignal(int value)
+		{
+			Value = value;
+		}
+	}
+}

Tests/SignalTests/SignalCenterTests.cs

@@ -0,0 +1,54 @@
+using System;
+using Gum.Signal.Core;
+using NUnit.Framework;
+
+namespace Tests.SignalTests
+{
+	[TestFixture]
+	public class SignalCenterTests
+	{
+		private SignalCenter _signalCenter;
+
+		private const int VALUE = 5;
+
+		[SetUp]
+		public void Setup()
+		{
+			_signalCenter = new SignalCenter();
+		}
+
+		[Test]
+		public void Subscribe()
+		{
+			void Action(FooSignal _) { }
+
+			_signalCenter.Subscribe((Action<FooSignal>)Action);
+			Assert.IsTrue(_signalCenter.Exists<FooSignal>(Action));
+		}
+
+		[Test]
+		public void Unsubscribe()
+		{
+			void Action(FooSignal _) { }
+
+			_signalCenter.Subscribe((Action<FooSignal>)Action);
+			Assert.IsTrue(_signalCenter.Exists<FooSignal>(Action));
+			_signalCenter.Unsubscribe((Action<FooSignal>)Action);
+			Assert.IsFalse(_signalCenter.Exists<FooSignal>(Action));
+		}
+
+		[Test]
+		public void Subscribe_And_Fire()
+		{
+			void Action(FooSignal fooSignal)
+			{
+				Assert.AreEqual(VALUE, fooSignal.Value);
+			}
+
+			_signalCenter.Subscribe<FooSignal>(Action);
+			Assert.IsTrue(_signalCenter.Exists<FooSignal>(Action));
+
+			_signalCenter.Fire(new FooSignal(VALUE));
+		}
+	}
+}

Tests/Tests.csproj

@@ -17,6 +17,7 @@
       <ProjectReference Include="..\Gum.Composer\Gum.Composer.csproj" />
       <ProjectReference Include="..\Gum.Core\Gum.Core.csproj" />
       <ProjectReference Include="..\Gum.Pooling\Gum.Pooling.csproj" />
+      <ProjectReference Include="..\Gum.Signal\Gum.Signal.csproj" />
     </ItemGroup>
 
 </Project>