From 8772fb3f93ff313a53fb7dd99a46e857ec2d3827 Mon Sep 17 00:00:00 2001
From: Curtis Wensley <curtis.wensley@gmail.com>
Date: Fri, 2 Jun 2023 14:58:40 -0700
Subject: [PATCH] Mac: Fix inserting items at the beginning of a
 SegmentedButton

---
 .../Forms/Controls/SegmentedButtonHandler.cs    | 11 ++++-------
 .../Forms/Controls/SegmentedButtonTests.cs      | 17 +++++++++++++++++
 2 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/src/Eto.Mac/Forms/Controls/SegmentedButtonHandler.cs b/src/Eto.Mac/Forms/Controls/SegmentedButtonHandler.cs
index 802d103d37..b3ff05572b 100644
--- a/src/Eto.Mac/Forms/Controls/SegmentedButtonHandler.cs
+++ b/src/Eto.Mac/Forms/Controls/SegmentedButtonHandler.cs
@@ -371,16 +371,13 @@ public void ClearItems()
 
 		public void InsertItem(int index, SegmentedItem item)
 		{
-			var count = ++Control.SegmentCount;
+			var count = Control.SegmentCount++;
 
 			// need to copy items as we can't insert items
-			if (index < count - 1)
+			for (nint i = index; i < count; i++)
 			{
-				for (nint i = index; i < count; i++)
-				{
-					var next = i - 1;
-					CopyItem(i, next);
-				}
+				var next = i + 1;
+				CopyItem(i, next);
 			}
 			SetItem(index, item);
 			if (item.Selected)
diff --git a/test/Eto.Test/UnitTests/Forms/Controls/SegmentedButtonTests.cs b/test/Eto.Test/UnitTests/Forms/Controls/SegmentedButtonTests.cs
index cc5e3996c2..e3604f97e8 100644
--- a/test/Eto.Test/UnitTests/Forms/Controls/SegmentedButtonTests.cs
+++ b/test/Eto.Test/UnitTests/Forms/Controls/SegmentedButtonTests.cs
@@ -517,5 +517,22 @@ public void SelectAllAndClearSelectionShouldTriggerSelectedChanges()
 			Assert.AreEqual(2, item2SelectedChanged, "#6.7.2");
 			Assert.AreEqual(2, item3SelectedChanged, "#6.7.3");
 		}
+		
+		[Test]
+		[InvokeOnUI]
+		public void InsertingItemsShouldWork()
+		{
+			var segmentedButton = new SegmentedButton();
+			segmentedButton.Items.Add(new ButtonSegmentedItem { Text = "Item 1" });
+			segmentedButton.Items.Add(new ButtonSegmentedItem { Text = "Item 2" });
+			segmentedButton.Items.Add(new ButtonSegmentedItem { Text = "Item 3" });
+
+			// insert at beginning
+			segmentedButton.Items.Insert(0, new ButtonSegmentedItem { Text = "Item Beginning" });
+			// insert at middle
+			segmentedButton.Items.Insert(1, new ButtonSegmentedItem { Text = "Item Middle" });
+			// insert at end
+			segmentedButton.Items.Insert(segmentedButton.Items.Count, new ButtonSegmentedItem { Text = "Item End" });
+		}
 	}
 }
\ No newline at end of file