Merge pull request #5 from iancoetzer/master

Introduce disposing of CanvasBase (Ids) to prevent calling event handers on disposed canvas base instances
mizrael · Jun 27, 2024 · c1da363 · c1da363
2 parents d5518ff + 8788454
commit c1da363
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Showing 2 changed files with 32 additions and 4 deletions.
diff --git a/src/Blazorex/CanvasBase.cs b/src/Blazorex/CanvasBase.cs
@@ -5,8 +5,10 @@
 
 namespace Blazorex
 {
-    public class CanvasBase : ComponentBase
+    public class CanvasBase : ComponentBase, IAsyncDisposable
     {
+        private bool _disposed = false;
+
         protected override async Task OnInitializedAsync()
         {
             if (this.CanvasManager is null)
@@ -110,5 +112,18 @@ public async ValueTask Resized(int width, int height)
         public IRenderContext RenderContext { get; private set; }
 
         #endregion Properties
+
+        #region Disposing
+        public async ValueTask DisposeAsync()
+        {
+            if (!_disposed)
+            {
+                // Call javascript to delete this canvas Id from the _contexts array
+                await JSRuntime.InvokeVoidAsync("Blazorex.removeContext", Id);
+
+                _disposed = true;
+            }
+        }
+        #endregion Disposing
     }
 }
diff --git a/src/Blazorex/wwwroot/blazorex.js b/src/Blazorex/wwwroot/blazorex.js
@@ -79,7 +79,16 @@ window.Blazorex = (() => {
         }
 
         return result;
-    };
+    },
+    removeContext = (ctxId) => {
+        const ctx = _contexts[ctxId].context; 
+        if (!ctx){
+            return ;
+        }
+
+        delete _contexts[ctxId]; 
+    }
+    ;
 
     window.onkeyup = (e) => {
         for (let ctx in _contexts) {
@@ -112,8 +121,12 @@ window.Blazorex = (() => {
         createImageData,
         putImageData,
         processBatch,
-        directCall
+        directCall,
+        removeContext
     };
 })();
 
-window.requestAnimationFrame(Blazorex.onFrameUpdate);
+window.requestAnimationFrame(Blazorex.onFrameUpdate);
+
+
+