From 0c74dfc38efa3859b8aabbed67b5111e6c61ab66 Mon Sep 17 00:00:00 2001
From: Ellpeck <megamaximal@gmail.com>
Date: Thu, 5 Dec 2019 14:59:53 +0100
Subject: [PATCH] allow for ui element removal during its update

---
 MLEM.Ui/Elements/Element.cs | 3 ++-
 MLEM.Ui/UiSystem.cs         | 5 +++--
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/MLEM.Ui/Elements/Element.cs b/MLEM.Ui/Elements/Element.cs
index b8d058b..e14157a 100644
--- a/MLEM.Ui/Elements/Element.cs
+++ b/MLEM.Ui/Elements/Element.cs
@@ -442,7 +442,8 @@ namespace MLEM.Ui.Elements {
             this.System.OnElementUpdated?.Invoke(this, time);
 
             foreach (var child in this.GetRelevantChildren())
-                child.Update(time);
+                if (child.System != null)
+                    child.Update(time);
         }
 
         public virtual void Draw(GameTime time, SpriteBatch batch, float alpha, BlendState blendState, SamplerState samplerState, Matrix matrix) {
diff --git a/MLEM.Ui/UiSystem.cs b/MLEM.Ui/UiSystem.cs
index c592b90..a69b417 100644
--- a/MLEM.Ui/UiSystem.cs
+++ b/MLEM.Ui/UiSystem.cs
@@ -98,8 +98,9 @@ namespace MLEM.Ui {
         public void Update(GameTime time) {
             this.Controls.Update();
 
-            foreach (var root in this.rootElements)
-                root.Element.Update(time);
+            for (var i = this.rootElements.Count - 1; i >= 0; i--) {
+                this.rootElements[i].Element.Update(time);
+            }
         }
 
         public void DrawEarly(GameTime time, SpriteBatch batch) {