From 53329b7068c5eee13e8aea2ee456f134a5a24786 Mon Sep 17 00:00:00 2001
From: deniz1a <deniz1a@deniz1a>
Date: Sun, 2 Aug 2015 22:13:21 +0300
Subject: [PATCH] Makes dropdown menus auto-scroll to selected item.

---
 .../Widgets/DropDownButtonWidget.cs           |  4 +++
 .../Widgets/ScrollPanelWidget.cs              | 35 +++++++++++++------
 2 files changed, 29 insertions(+), 10 deletions(-)

diff --git a/OpenRA.Mods.Common/Widgets/DropDownButtonWidget.cs b/OpenRA.Mods.Common/Widgets/DropDownButtonWidget.cs
index 7cb6fe03ca..a679a5c4ed 100644
--- a/OpenRA.Mods.Common/Widgets/DropDownButtonWidget.cs
+++ b/OpenRA.Mods.Common/Widgets/DropDownButtonWidget.cs
@@ -94,6 +94,10 @@ namespace OpenRA.Mods.Common.Widgets
 				oldBounds.Width,
 				oldBounds.Height);
 			panelRoot.AddChild(panel);
+
+			var scrollPanel = panel as ScrollPanelWidget;
+			if (scrollPanel != null)
+				scrollPanel.ScrollToSelectedItem();
 		}
 
 		public void ShowDropDown<T>(string panelTemplate, int maxHeight, IEnumerable<T> options, Func<T, ScrollItemWidget, ScrollItemWidget> setupItem)
diff --git a/OpenRA.Mods.Common/Widgets/ScrollPanelWidget.cs b/OpenRA.Mods.Common/Widgets/ScrollPanelWidget.cs
index 02ef449ff7..9658a736b9 100644
--- a/OpenRA.Mods.Common/Widgets/ScrollPanelWidget.cs
+++ b/OpenRA.Mods.Common/Widgets/ScrollPanelWidget.cs
@@ -214,17 +214,8 @@ namespace OpenRA.Mods.Common.Widgets
 			get { return targetListOffset == Math.Min(0, Bounds.Height - ContentHeight) || ContentHeight <= Bounds.Height; }
 		}
 
-		public void ScrollToItem(string itemKey, bool smooth = false)
+		void ScrollToItem(Widget item, bool smooth = false)
 		{
-			var item = Children.FirstOrDefault(c =>
-			{
-				var si = c as ScrollItemWidget;
-				return si != null && si.ItemKey == itemKey;
-			});
-
-			if (item == null)
-				return;
-
 			// Scroll the item to be visible
 			float? newOffset = null;
 			if (item.Bounds.Top + currentListOffset < 0)
@@ -237,6 +228,30 @@ namespace OpenRA.Mods.Common.Widgets
 				SetListOffset(newOffset.Value, smooth);
 		}
 
+		public void ScrollToItem(string itemKey, bool smooth = false)
+		{
+			var item = Children.FirstOrDefault(c =>
+			{
+				var si = c as ScrollItemWidget;
+				return si != null && si.ItemKey == itemKey;
+			});
+
+			if (item != null)
+				ScrollToItem(item, smooth);
+		}
+
+		public void ScrollToSelectedItem()
+		{
+			var item = Children.FirstOrDefault(c =>
+			{
+				var si = c as ScrollItemWidget;
+				return si != null && si.IsSelected();
+			});
+
+			if (item != null)
+				ScrollToItem(item);
+		}
+
 		public override void Tick()
 		{
 			if (upPressed)