Solution

src/main/java/lab/App.java

 package lab;
 
 import javafx.application.Application;
+import javafx.fxml.FXMLLoader;
 import javafx.scene.Group;
 import javafx.scene.Scene;
 import javafx.scene.canvas.Canvas;
+import javafx.scene.layout.BorderPane;
 import javafx.stage.Stage;
 import javafx.stage.WindowEvent;
 
@@ -17,7 +19,7 @@ public class App extends Application {
 		launch(args);
 	}
 	
-	private Canvas canvas;
+	
 	private GameController controller;
 	@Override
 	public void start(Stage primaryStage) {
@@ -25,9 +27,12 @@ public class App extends Application {
 			//Construct a main window with a canvas.  
 			
 			
-			Group root = new Group();
-			canvas = new Canvas(800, 600);
-			root.getChildren().add(canvas);
+			//Group root = new Group();
+			//canvas = new Canvas(800, 600);
+			//root.getChildren().add(canvas);
+			
+			FXMLLoader loader = new FXMLLoader(getClass().getResource("GameView.fxml"));
+			BorderPane root = loader.load();
 			Scene scene = new Scene(root);
 			
 			
@@ -35,7 +40,8 @@ public class App extends Application {
 			primaryStage.resizableProperty().set(false);
 			primaryStage.setTitle("Java 1 - 5th laboratory");
 			primaryStage.show();
-			controller = new GameController(canvas);
+			
+			controller = loader.getController();
 			controller.startGame();
 			//Exit program when main window is closed
 			primaryStage.setOnCloseRequest(this::exitProgram);

src/main/java/lab/BulletAnimated.java

@@ -15,7 +15,7 @@ public class BulletAnimated  implements DrawableSimulable, Collisionable{
 	private double mass = 2;
 	private double strenghtOfCannon = 100;
 	private double cannonLength = 100;
-	private boolean accelerate = true;
+	private boolean accelerate = false;
 	private boolean hitToGround = false;
 
 	private double crossSectionalArea;
@@ -49,6 +49,9 @@ public class BulletAnimated  implements DrawableSimulable, Collisionable{
 	}
 
 	public void simulate(double deltaT) {
+		if (!accelerate && position == start) {
+			return;
+		}
 		if (accelerate && start.distance(position) < cannonLength) {
 			double cannonAngle = cannon.getAngle(); 
 			speed = speed
@@ -90,7 +93,12 @@ public class BulletAnimated  implements DrawableSimulable, Collisionable{
 		position = start;
 		speed = initialSpeed;
 		hitToGround = false;
+	}
+
+	public void fire() {
+		reload();
 		accelerate = true;
+		
 	}
 	
 }

src/main/java/lab/Cannon.java

@@ -24,10 +24,7 @@ public class Cannon implements DrawableSimulable {
 	}
 
 	public void simulate(double timeStep) {
-		angle = angle + direction*0.8;
-		if(angle <=-90 || angle >= 0) {
-			direction*=-1;
-		}
+		
 	}
 	
 	public void draw(GraphicsContext gc) {
@@ -46,4 +43,9 @@ public class Cannon implements DrawableSimulable {
 	public double getAngle() {
 		return (angle * -1) / 180 * Math.PI;
 	}
+
+	public void setAngle(double value) {
+		angle = value;
+		
+	}
 }

src/main/java/lab/GameController.java

 package lab;
 
 import javafx.animation.AnimationTimer;
+import javafx.fxml.FXML;
 import javafx.scene.canvas.Canvas;
+import javafx.scene.control.Button;
+import javafx.scene.control.Slider;
 
 public class GameController {
 
 	private World world;
+	
+	@FXML
 	private Canvas canvas;
+	
+	@FXML
+	private Slider angleSlider;
+	
+	@FXML
+	private Slider forceSlider;
+	
+	
 	private AnimationTimer animationTimer;
 	
-	public GameController(Canvas canvas) {
-		this.canvas = canvas;
+	public GameController() {
 	}
 	
 	public void startGame() {
 		this.world = new World(canvas.getWidth(), canvas.getHeight());	
+		
+		this.angleSlider.valueProperty().addListener( (obj, oldValue, newValue) -> world.setCannonAngle(newValue.doubleValue()));
 		//Draw scene on a separate thread to avoid blocking UI.
+		
+		world.setCannonAngle(this.angleSlider.getValue());
 		animationTimer = new DrawingThread(canvas, world);
 		animationTimer.start();
 	}
@@ -25,5 +41,8 @@ public class GameController {
 		animationTimer.stop();
 	}
 
-	
+	@FXML
+	private void firePressed() {
+		world.fireBullet();
+	}
 }

src/main/java/lab/World.java

@@ -78,4 +78,20 @@ public class World {
 		this.height = height;
 	}
 
+	public void setCannonAngle(double doubleValue) {
+		for (DrawableSimulable entity: entities) {
+			if (entity instanceof Cannon cannon) {
+				cannon.setAngle(doubleValue);
+			}
+		}
+	}
+
+	public void fireBullet() {
+		for (DrawableSimulable entity: entities) {
+			if (entity instanceof BulletAnimated bullet) {
+				bullet.fire();
+			}
+		}		
+	}
+
 }

src/main/resources/lab/GameView.fxml

+<?xml version="1.0" encoding="UTF-8"?>
+
+<?import javafx.geometry.Insets?>
+<?import javafx.scene.canvas.Canvas?>
+<?import javafx.scene.control.Button?>
+<?import javafx.scene.control.Slider?>
+<?import javafx.scene.layout.BorderPane?>
+<?import javafx.scene.layout.HBox?>
+
+
+<BorderPane maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" xmlns="http://javafx.com/javafx/18" xmlns:fx="http://javafx.com/fxml/1" fx:controller="lab.GameController">
+   <center>
+      <Canvas fx:id="canvas" height="400.0" width="600.0" BorderPane.alignment="CENTER" />
+   </center>
+   <bottom>
+      <HBox BorderPane.alignment="CENTER">
+         <children>
+            <Slider  fx:id="angleSlider" max="0.0" min="-90.0" showTickLabels="true" showTickMarks="true" value="45.0" HBox.hgrow="ALWAYS">
+               <HBox.margin>
+                  <Insets bottom="13.0" left="13.0" right="13.0" top="13.0" />
+               </HBox.margin>
+            </Slider>
+            <Button onAction="#firePressed" mnemonicParsing="false" text="Fire" HBox.hgrow="ALWAYS">
+               <HBox.margin>
+                  <Insets bottom="13.0" left="13.0" right="13.0" top="13.0" />
+               </HBox.margin>
+            </Button>
+            <Slider fx:id="forceSlider" max="210.0" min="10.0" showTickLabels="true" showTickMarks="true" value="50.0" HBox.hgrow="ALWAYS">
+               <HBox.margin>
+                  <Insets bottom="13.0" left="13.0" right="13.0" top="13.0" />
+               </HBox.margin>
+            </Slider>
+         </children>
+      </HBox>
+   </bottom>
+</BorderPane>