diff --git a/Tusker/Screens/Compose/ComposeDrawingViewController.swift b/Tusker/Screens/Compose/ComposeDrawingViewController.swift
index 29d89e7e..43005101 100644
--- a/Tusker/Screens/Compose/ComposeDrawingViewController.swift
+++ b/Tusker/Screens/Compose/ComposeDrawingViewController.swift
@@ -80,12 +80,13 @@ class ComposeDrawingViewController: UIViewController {
         
         updateLayout(for: toolPicker)
         canvasView.becomeFirstResponder()
+    }
+    
+    override func viewDidAppear(_ animated: Bool) {
+        super.viewDidAppear(animated)
         
-        // wait until the next run loop iteration so that the canvas view has become first responder and it's undo manager exists
-        DispatchQueue.main.async {
-            NotificationCenter.default.addObserver(self, selector: #selector(self.updateUndoRedoButtonState), name: .NSUndoManagerDidUndoChange, object: self.undoManager!)
-            NotificationCenter.default.addObserver(self, selector: #selector(self.updateUndoRedoButtonState), name: .NSUndoManagerDidRedoChange, object: self.undoManager!)
-        }
+        NotificationCenter.default.addObserver(self, selector: #selector(self.updateUndoRedoButtonState), name: .NSUndoManagerDidUndoChange, object: self.undoManager!)
+        NotificationCenter.default.addObserver(self, selector: #selector(self.updateUndoRedoButtonState), name: .NSUndoManagerDidRedoChange, object: self.undoManager!)
     }
 
     func updateLayout(for toolPicker: PKToolPicker) {