change1 restart on new project

code App.java

src/main/java/App.java

+import javafx.application.Application;
+import javafx.scene.Group;
+import javafx.scene.Scene;
+import javafx.scene.control.Button;
+import javafx.scene.layout.HBox;
+import javafx.scene.layout.VBox;
+import javafx.stage.Stage;
+
+import java.util.concurrent.ScheduledThreadPoolExecutor;
+import java.util.concurrent.TimeUnit;
+
+
+public class App extends Application {
+
+    boolean isInPause = true;
+
+    public static void main(String[] args) {
+        launch(args);
+    }
+
+    @Override
+    public void start(Stage primaryStage) {
+        Group root = new Group();
+        Button restart = new Button("Restart");
+        Button switchPause = new Button("Pause");
+        VBox buttons = new VBox();
+        HBox total = new HBox();
+        Grid grid = new Grid(700,700,20,20);
+
+        root.getChildren().add(total);
+        total.getChildren().add(buttons);
+        total.getChildren().add(grid);
+        buttons.getChildren().add(restart);
+        buttons.getChildren().add(switchPause);
+        restart.setOnMouseClicked(grid::restart);
+        switchPause.setOnMouseClicked((value)->isInPause = !isInPause);
+        primaryStage.setScene(new Scene(root));
+        primaryStage.show();
+        grid.repaint();
+
+        ScheduledThreadPoolExecutor threadPoolExecutor = new ScheduledThreadPoolExecutor(1);
+        threadPoolExecutor.scheduleAtFixedRate(() -> {
+            if(!isInPause) {
+                grid.model.activation();
+                grid.repaint();
+            }
+        }, 0, 50 , TimeUnit.MILLISECONDS);
+    }
+}