diff --git a/lib/app_component.dart b/lib/app_component.dart
index afce95f..c23443e 100644
--- a/lib/app_component.dart
+++ b/lib/app_component.dart
@@ -48,5 +48,8 @@ class AppComponent implements OnInit {
     engine.reset();
   }
 
-  void onRandomClicked() {}
+  void onRandomClicked() {
+    engine.running = false;
+    engine.grid.addPattern();
+  }
 }
diff --git a/lib/src/Grid.dart b/lib/src/Grid.dart
index 5730461..062a78c 100644
--- a/lib/src/Grid.dart
+++ b/lib/src/Grid.dart
@@ -83,6 +83,7 @@ class Grid {
         }
         break;
     }
+    _dirty = true;
   }
 
   void setCellState(int x, int y, bool state) {