NPE bei Verwenden von ActionListener!

[Luk10]

Hallo,

Ich habe ein Programm geschrieben welches ein Image lädt und über ein Panel bewegen lässt!
Das Image referenziere ich über eine eigene Klasse, in welcher auch x und y koord. gespeichert sind!

Nun will ich Objekte dieser Klasse via actionListener und Button erstellen!
Dabei kriege ich eine NPE und ich finde den Fehler nicht!

package seb.zelle;

import seb.login.*;

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.util.*;

public class ZellenGui extends JPanel implements Runnable {
  private boolean game_running;
  private int speed;
  private boolean stopped;
  
  ArrayList<Zelle> list;
  Zelle zelle;
  
  public static void starten() {
      new ZellenGui(450, 400);
   }
  public ZellenGui (int w, int h) {
      this.setPreferredSize(new Dimension(w, h));
      JFrame frame = new JFrame("Zelle");
      game_running = true;
      stopped = true;
      
      /** GUI-INITIALISIEREN */
      JPanel hauptPanel = new JPanel();
      hauptPanel.setLayout(new BoxLayout(hauptPanel, BoxLayout.Y_AXIS));
      
      JButton start_stoppButton = new JButton("Start/Stopp");
      JButton erstellenButton = new JButton("Zelle erstellen");
      JButton speed = new JButton("Speed up/down");
      hauptPanel.add(start_stoppButton);
      hauptPanel.add(erstellenButton);
      hauptPanel.add(speed);
      
      start_stoppButton.addActionListener(new Start_stoppButtonListener());
      erstellenButton.addActionListener(new ErstellenListener());
      speed.addActionListener(new SpeedListener());
      
      frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      frame.setSize(600, 400);
      frame.getContentPane().add(BorderLayout.WEST, this);
      frame.getContentPane().add(BorderLayout.EAST, hauptPanel);
      this.setBackground(Color.white);
      
      //System.out.println("Kostruktor abgeschlossen");
      
      initialisieren();
      frame.setVisible(true);
      
      //System.out.println("Initialisieren abgeschlossen");
    }

    private void initialisieren () {
        /**
        Hier wurde die Zelle vorher initialisiert!
        */
        //zelle = new Zelle(200, 200, this, "F:/Info/LoginGUI.2/pics/zelle4.png", "F:/Info/LoginGUI.2/pics/hintergrund1.png");
        list = new ArrayList<Zelle>();
        list.add(zelle);
        
        //repaint();
        
        Thread t = new Thread(this);
        t.start();
        //System.out.println("Nach initialisieren");
    }
    public void run () {
        try {
            Thread.sleep(1000); 
        } catch (Exception ex) {}   
        goSchleife();
        //System.out.println("Vor run");
        //System.out.println("Nach run");
    }
    public void goSchleife () {
        //System.out.println("Vor der Schleife");
        while (game_running == true) {
          while (stopped == false) {
            //Move-Methoden abrufen
                
            }
        }
    }   
}
    public void paintComponent (Graphics g) {
        super.paintComponent(g);
        
        //System.out.println("Vorm zeichnen");
        
         for (Drawable draw : list) {
               draw.drawObjects(g);
               //System.out.println("Object gezeichnet");
            }
        }
    public ZellenGui getGui () {
        return this;
    }
    
    class Start_stoppButtonListener implements ActionListener {
        public void actionPerformed (ActionEvent ev) {
            if (!stopped) {
                stopped = true;
            }
            else {
                stopped = false;
            }
        }
    }
    class SpeedListener implements ActionListener {
        public void actionPerformed (ActionEvent ev) {      
        }
    }
    class ErstellenListener implements ActionListener {
        public void actionPerformed (ActionEvent ev) {
            zelle = new Zelle(200, 200, getGui(), "F:/Info/LoginGUI.2/pics/zelle4.png", "F:/Info/LoginGUI.2/pics/hintergrund1.png");
            stopped = false;
        }
    }
}

Dazu die Klasse Zelle:

package seb.zelle;

import seb.*;

import java.awt.*;
import javax.swing.*;
import java.util.*;

public class Zelle implements Drawable, Moveable {
  
  ZellenGui gamePanel;
  Image image;
  Image image_h;
  String path;
  
  private int speed_1;
  private int speed_2;
  private int speed_3;
  
  private int x;
  private int y;
  private int rndZahl;
  
  private int a;
  private boolean kleinerN;
  
  private int zahl_1;
  private int zahl_2;
  private int zahl_3;
  private int zahl_4;
  
  private int standart;
  
  public Zelle (int x, int y, ZellenGui z, String path, String path_h) {
      this.x = x;
      this.y = y;
      
      gamePanel = z;
      image = new ImageIcon(path).getImage();
      image_h = new ImageIcon(path_h).getImage();
      
      standart = 10;
      
      speed_1 = (int) Math.sqrt(2.0)*standart;
      speed_2 = (int) Math.sqrt(5.0)*standart;
      speed_3 = (int) Math.sqrt(10.0)*standart;
    }
    public void drawObjects (Graphics g) {
        g.drawImage(image_h, 0, 0, null);
        g.drawImage(image, x, y, null);
    }
    /**Move-Methoden */
    
    @Override
    public void move() {
      //Move-Methoden die ich hier weglasse!
    } 
    @Override
    public void zeichne (int i) {
        gamePanel.repaint();
        try {
            Thread.sleep(i);
        } catch (Exception ex) {
        }
    }
}

Die methode move() ist aus dem interface Moveable überschrieben! Genauso die Methode zeichne()

Kann mir jemand mit meiner NPE helfen?

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at seb.zelle.ZellenGui.paintComponent(ZellenGui.java:93)
at javax.swing.JComponent.paint(JComponent.java:1017)
at javax.swing.JComponent.paintChildren(JComponent.java:852)
at javax.swing.JComponent.paint(JComponent.java:1026)
at javax.swing.JComponent.paintChildren(JComponent.java:852)
at javax.swing.JComponent.paint(JComponent.java:1026)
at javax.swing.JLayeredPane.paint(JLayeredPane.java:567)
at javax.swing.JComponent.paintChildren(JComponent.java:852)
at javax.swing.JComponent.paintToOffscreen(JComponent.java:5119)
at javax.swing.BufferStrategyPaintManager.paint(BufferStrategyPaintManager.java:278)
at javax.swing.RepaintManager.paint(RepaintManager.java:1220)
at javax.swing.JComponent.paint(JComponent.java:1003)
at java.awt.GraphicsCallback$PaintCallback.run(GraphicsCallback.java:21)
at sun.awt.SunGraphicsCallback.runOneComponent(SunGraphicsCallback.java:60)
at sun.awt.SunGraphicsCallback.runComponents(SunGraphicsCallback.java:97)
at java.awt.Container.paint(Container.java:1780)
at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:814)
at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:714)
at javax.swing.RepaintManager.seqPaintDirtyRegions(RepaintManager.java:694)
at javax.swing.SystemEventQueueUtilities$ComponentWorkRequest.run(SystemEventQueueUtilities.java:125)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:597)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)


Danke, Luk

 

[Marco13]

Mach' mal in Zeile 92 ein
System.out.println("Vorm zeichnen: "+list);
und schau ob in der list 'null' vorkommt. (Ja, tut es ) Und schau dann, wo dieses 'null' in die list gelegt wird... Ich tippe auf Zeile 63 von ZellenGUI: Dort wird eine zelle reingelegt, die dort vermutlich noch null ist...

 

[Luk10]

Danke!

Luk