Added UiSystem.OnElementAreaDirty and Element.OnAreaDirty events

Author: Ellpeck

CHANGELOG.md

@@ -1,9 +1,11 @@
 # Changelog
 MLEM uses [semantic versioning](https://semver.org/). Potentially breaking changes are written in **bold**. Each newly released version also has a corresponding [tag](https://github.com/Ellpeck/MLEM/tags).
 
-## 8.0.1 (In Development)
+## 8.1.0 (In Development)
 
-No code changes
+### MLEM.Ui
+Additions
+- Added UiSystem.OnElementAreaDirty and Element.OnAreaDirty events
 
 ## 8.0.0
 

MLEM.Ui/Elements/Element.cs

@@ -439,6 +439,10 @@ public StyleProp<Padding> ChildPadding {
         /// </summary>
         public TextInputCallback OnTextInput;
         /// <summary>
+        /// Event that is called when this element's area is marked dirty using <see cref="Element.SetAreaDirty"/>.
+        /// </summary>
+        public GenericCallback OnAreaDirty;
+        /// <summary>
         /// Event that is called when this element's <see cref="DisplayArea"/> is changed.
         /// </summary>
         public GenericCallback OnAreaUpdated;
@@ -653,6 +657,7 @@ public virtual void ForceUpdateSortedChildren() {
         /// </summary>
         public void SetAreaDirty() {
             this.AreaDirty = true;
+            this.System?.InvokeOnElementAreaDirty(this);
             this.Parent?.OnChildAreaDirty(this, false);
         }
 

MLEM.Ui/UiSystem.cs

@@ -141,6 +141,10 @@ public UiStyle Style {
         /// </summary>
         public event Element.GenericCallback OnElementTouchExit;
         /// <summary>
+        /// Event that is invoked when an <see cref="Element"/>'s display area is marked dirty
+        /// </summary>
+        public event Element.GenericCallback OnElementAreaDirty;
+        /// <summary>
         /// Event that is invoked when an <see cref="Element"/>'s display area changes
         /// </summary>
         public event Element.GenericCallback OnElementAreaUpdated;
@@ -204,6 +208,7 @@ public UiSystem(Game game, UiStyle style, InputHandler inputHandler = null, bool
             this.OnElementMouseExit += e => e.OnMouseExit?.Invoke(e);
             this.OnElementTouchEnter += e => e.OnTouchEnter?.Invoke(e);
             this.OnElementTouchExit += e => e.OnTouchExit?.Invoke(e);
+            this.OnElementAreaDirty += e => e.OnAreaDirty?.Invoke(e);
             this.OnElementAreaUpdated += e => e.OnAreaUpdated?.Invoke(e);
             this.OnElementStyleInit += e => e.OnStyleInit?.Invoke(e);
             this.OnMousedElementChanged += e => this.ApplyToAll(t => t.OnMousedElementChanged?.Invoke(t, e));
@@ -400,6 +405,10 @@ internal void InvokeOnElementUpdated(Element element, GameTime time) {
             this.OnElementUpdated?.Invoke(element, time);
         }
 
+        internal void InvokeOnElementAreaDirty(Element element) {
+            this.OnElementAreaDirty?.Invoke(element);
+        }
+
         internal void InvokeOnElementAreaUpdated(Element element) {
             this.OnElementAreaUpdated?.Invoke(element);
         }

Tests/TestGame.cs

@@ -36,6 +36,7 @@ protected override void LoadContent() {
 #endif
         ));
         // make sure we catch a potential ui stack overflow as part of the tests by ensuring a sufficient execution stack
+        this.UiSystem.OnElementAreaDirty += _ => RuntimeHelpers.EnsureSufficientExecutionStack();
         this.UiSystem.OnElementAreaUpdated += _ => RuntimeHelpers.EnsureSufficientExecutionStack();
     }
 

build.cake

@@ -2,7 +2,7 @@
 #tool dotnet:?package=docfx&version=2.78.3
 
 // this is the upcoming version, for prereleases
-var version = Argument("version", "8.0.1");
+var version = Argument("version", "8.1.0");
 var target = Argument("target", "Default");
 var gitRef = Argument("ref", "refs/heads/main");
 var buildNum = Argument("buildNum", "");