Pass WidgetArgs to Widget.Initialize. Use this to allow for custom substitutions.

OpenRA.Game/Widgets/Widget.cs

@@ -95,14 +95,17 @@ namespace OpenRA.Widgets
         public virtual int2 ChildOrigin { get { return RenderOrigin; } }
         public virtual Rectangle RenderBounds { get { return new Rectangle(RenderOrigin.X, RenderOrigin.Y, Bounds.Width, Bounds.Height); } }
 
-        public virtual void Initialize()
+        public virtual void Initialize(WidgetArgs args)
         {
             // Parse the YAML equations to find the widget bounds
             var parentBounds = (Parent == null)
                 ? new Rectangle(0, 0, Game.viewport.Width, Game.viewport.Height)
                 : Parent.Bounds;
 
-            var substitutions = new Dictionary<string, int>();
+			var substitutions = args.ContainsKey("substitutions") ?
+				new Dictionary<string, int>((Dictionary<string, int>)args["substitutions"]) :
+				new Dictionary<string, int>();
+
             substitutions.Add("WINDOW_RIGHT", Game.viewport.Width);
             substitutions.Add("WINDOW_BOTTOM", Game.viewport.Height);
             substitutions.Add("PARENT_RIGHT", parentBounds.Width);

OpenRA.Game/Widgets/WidgetLoader.cs

@@ -52,7 +52,7 @@ namespace OpenRA
 				if (child.Key != "Children")
 					FieldLoader.LoadField(widget, child.Key, child.Value.Value);
 
-			widget.Initialize();
+			widget.Initialize(args);
 
 			foreach (var child in node.Value.Nodes)
 				if (child.Key == "Children")

OpenRA.Mods.Cnc/Widgets/CncSettingsLogic.cs

@@ -219,9 +219,14 @@ namespace OpenRA.Mods.Cnc.Widgets
 		
 		void ShowGroupModifierDropdown(CncDropDownButtonWidget dropdown)
 		{
-			var panel = Game.LoadWidget(world, "LABEL_DROPDOWN_TEMPLATE", null, new WidgetArgs()) as ScrollPanelWidget;
-			var itemTemplate = panel.GetWidget<ScrollItemWidget>("TEMPLATE");
+			var substitutions = new Dictionary<string,int>() {{ "DROPDOWN_WIDTH", dropdown.Bounds.Width }};
 			
+			var panel = (ScrollPanelWidget)Game.LoadWidget(world, "LABEL_DROPDOWN_TEMPLATE", null, new WidgetArgs()
+			{
+				{ "substitutions", substitutions }
+			});
+
+			var itemTemplate = panel.GetWidget<ScrollItemWidget>("TEMPLATE");
 			var options = new List<Pair<string, Modifiers>>()
 			{
 				Pair.New("Ctrl", Modifiers.Ctrl),

OpenRA.Mods.RA/Widgets/RadarWidget.cs

@@ -42,9 +42,9 @@ namespace OpenRA.Mods.RA.Widgets
 			this.world = world;
 		}
 		
-		public override void Initialize()
+		public override void Initialize(WidgetArgs args)
 		{
-			base.Initialize();
+			base.Initialize(args);
 
 			var size = Math.Max(world.Map.Bounds.Width, world.Map.Bounds.Height);
 			previewScale = Math.Min(RenderBounds.Width * 1f / world.Map.Bounds.Width, RenderBounds.Height * 1f / world.Map.Bounds.Height);

OpenRA.Mods.RA/Widgets/SpecialPowerBinWidget.cs

@@ -34,9 +34,9 @@ namespace OpenRA.Mods.RA.Widgets
 			this.worldRenderer = worldRenderer;
 		}
 		
-		public override void Initialize()
+		public override void Initialize(WidgetArgs args)
 		{
-			base.Initialize();
+			base.Initialize(args);
 
 			spsprites = Rules.Info.Values.SelectMany( u => u.Traits.WithInterface<SupportPowerInfo>() )
 				.Select(u => u.Image).Distinct()

mods/cnc/chrome/dropdowns.yaml

@@ -74,7 +74,7 @@ Background@COLOR_CHOOSER:
 
 ScrollPanel@LABEL_DROPDOWN_TEMPLATE:
 	Id:LABEL_DROPDOWN_TEMPLATE
-	Width:100
+	Width:DROPDOWN_WIDTH
 	Children:
 		ScrollItem@TEMPLATE:
 			Id:TEMPLATE