Ich habe einen Score Actor hinzugefügt, welcher den Score oben im Bildschirm anzeigt und jede Sekunde um eins erhöht.

SMIMS-Game/MyWorld.java

@@ -30,6 +30,8 @@ public class MyWorld extends World
     {
         Player player = new Player();
         addObject(player,302,320);
+        Score score = new Score();
+        addObject(score, 200, 50);
     }
     public void act()
     {

SMIMS-Game/Score.ctxt

@@ -0,0 +1,11 @@
+#BlueJ class context
+comment0.target=Score
+comment0.text=\r\n\ Write\ a\ description\ of\ class\ UI\ here.\r\n\ \r\n\ @author\ (your\ name)\ \r\n\ @version\ (a\ version\ number\ or\ a\ date)\r\n
+comment1.params=
+comment1.target=void\ act()
+comment1.text=\r\n\ Act\ -\ do\ whatever\ the\ UI\ wants\ to\ do.\ This\ method\ is\ called\ whenever\r\n\ the\ 'Act'\ or\ 'Run'\ button\ gets\ pressed\ in\ the\ environment.\r\n
+comment2.params=
+comment2.target=void\ draw_score()
+comment3.params=
+comment3.target=int\ calculate_score()
+numComments=4

SMIMS-Game/Score.java

@@ -0,0 +1,29 @@
+import greenfoot.*;  // (World, Actor, GreenfootImage, Greenfoot and MouseInfo)
+
+/**
+ * Write a description of class UI here.
+ * 
+ * @author (your name) 
+ * @version (a version number or a date)
+ */
+public class Score extends Actor
+{
+    int timer;
+    /**
+     * Act - do whatever the UI wants to do. This method is called whenever
+     * the 'Act' or 'Run' button gets pressed in the environment.
+     */
+    public void act()
+    {
+        timer++;
+        draw_score();
+    }
+    
+    public void draw_score(){
+        setImage(new GreenfootImage("Score:" + calculate_score(), 24, Color.WHITE, Color.BLACK));
+    }
+    
+    public int calculate_score(){
+        return timer/60;
+    }
+}