Nullpointerexeption die ik niet opgelost krijg :/

[Azuma]

Hallo ik krijg dus iedere keer een nullpointerexeption maar vind het niet wat het moet worden :/.
Kan iemand mij mss helpen?

import javax.swing.*;
import javax.swing.border.MatteBorder;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
/**
 * Created with IntelliJ IDEA.
 * User: David
 * Date: 08/03/13
 * Time: 12:02
 * To change this template use File | Settings | File Templates.
 */
public class ButtonDemo extends JFrame
{
    private JButton StartButton;
    private JButton HighscoreButton;
    private JButton HelpButton;
    private JButton Spelregels;
    private JButton ExitButton;
    private JLabel label;
    private JPanel panel;
    private JPanel panel1;


    public ButtonDemo() throws HeadlessException
    {
        setTitle("Buttons");
        maakComponenten();
        maakLayout();
        voegListenersToe();
        toonFrame();
    }

    private void initComponenten(){
        // het aanmaken van de font
        Font font = new Font("Arial", Font.ITALIC, 20);
        Font font2 = new Font("Arial", Font.ITALIC, 50);

// het aanmaken van de knoppen/panels/ ...
        this.label = new JLabel("  Boggle  ");
        this.panel = new JPanel();
        this.panel1 = new JPanel();
        this.StartButton = new JButton("Start spel");
        this.HighscoreButton = new JButton("Score");
        this.Spelregels = new JButton("Spelregels");
        this.HelpButton = new JButton("Help");
        this.ExitButton = new JButton("Stop");

// lettertype aanpassen van de knoppen
        label.setFont(font2);
        StartButton.setFont(font);
        HighscoreButton.setFont(font);
        Spelregels.setFont(font);
        HelpButton.setFont(font);
        ExitButton.setFont(font);

// groote van de knoppen
        StartButton.setPreferredSize(new Dimension(150,30));
        HighscoreButton.setPreferredSize(new Dimension(150,30));
        Spelregels.setPreferredSize(new Dimension(150,30));
        HelpButton.setPreferredSize(new Dimension(150, 30));
        ExitButton.setPreferredSize(new Dimension(150,30));


    }

    private void maakComponenten() {

            GridLayout wippen = new GridLayout(4,1,10,10);
            setLayout(wippen);
            this.add(panel, BorderLayout.NORTH);
            panel.add(label, BorderLayout.NORTH);
            this.add(panel1, BorderLayout.SOUTH);
            panel1.add(StartButton, BorderLayout.SOUTH);
            panel1.add(HighscoreButton, BorderLayout.SOUTH);
            panel1.add(Spelregels, BorderLayout.SOUTH);
            panel1.add(HelpButton, BorderLayout.SOUTH);
            panel1.add(ExitButton, BorderLayout.SOUTH);

    }


    private void maakLayout()
    {
        JPanel buttonPanel = new JPanel(new GridLayout(4,2,5,9));
        buttonPanel.add(StartButton);
        buttonPanel.add(HighscoreButton);
        buttonPanel.add(HelpButton);
        buttonPanel.add(Spelregels);
        buttonPanel.add(ExitButton);

        add(buttonPanel, BorderLayout.PAGE_END);
        add(buttonPanel, BorderLayout.CENTER);
    }

    private void voegListenersToe()
    {

    }

    private void stopMethode() {
    }

    private void toonFrame()
    {
        setBackground(Color.cyan);
        setBounds(200, 200, 200, 200);
        pack();
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setVisible(true);

    }
// inner class


}

"C:\Program Files\Java\jdk1.7.0_07\bin\java" -Didea.launcher.port=7548 "-Didea.launcher.bin.path=C:\Program Files (x86)\JetBrains\IntelliJ IDEA 11.1.3\bin" -Dfile.encoding=UTF-8 -classpath "C:\Program Files\Java\jdk1.7.0_07\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.7.0_07\jre\lib\deploy.jar;C:\Program Files\Java\jdk1.7.0_07\jre\lib\javaws.jar;C:\Program Files\Java\jdk1.7.0_07\jre\lib\jce.jar;C:\Program Files\Java\jdk1.7.0_07\jre\lib\jfr.jar;C:\Program Files\Java\jdk1.7.0_07\jre\lib\jfxrt.jar;C:\Program Files\Java\jdk1.7.0_07\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.7.0_07\jre\lib\management-agent.jar;C:\Program Files\Java\jdk1.7.0_07\jre\lib\plugin.jar;C:\Program Files\Java\jdk1.7.0_07\jre\lib\resources.jar;C:\Program Files\Java\jdk1.7.0_07\jre\lib\rt.jar;C:\Program Files\Java\jdk1.7.0_07\jre\lib\ext\access-bridge-64.jar;C:\Program Files\Java\jdk1.7.0_07\jre\lib\ext\dnsns.jar;C:\Program Files\Java\jdk1.7.0_07\jre\lib\ext\jaccess.jar;C:\Program Files\Java\jdk1.7.0_07\jre\lib\ext\localedata.jar;C:\Program Files\Java\jdk1.7.0_07\jre\lib\ext\sunec.jar;C:\Program Files\Java\jdk1.7.0_07\jre\lib\ext\sunjce_provider.jar;C:\Program Files\Java\jdk1.7.0_07\jre\lib\ext\sunmscapi.jar;C:\Program Files\Java\jdk1.7.0_07\jre\lib\ext\zipfs.jar;F:\Oefening4\out\production\Oefening4;C:\Program Files (x86)\JetBrains\IntelliJ IDEA 11.1.3\lib\idea_rt.jar" com.intellij.rt.execution.application.AppMain RunButtons
Exception in thread "main" java.lang.NullPointerException
	at java.awt.Container.addImpl(Container.java:1086)
	at java.awt.Container.add(Container.java:998)
	at javax.swing.JFrame.addImpl(JFrame.java:562)
	at java.awt.Container.add(Container.java:966)
	at ButtonDemo.maakComponenten(ButtonDemo.java:71)
	at ButtonDemo.<init>(ButtonDemo.java:28)
	at RunButtons.main(RunButtons.java:18)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:601)
	at com.intellij.rt.execution.application.AppMain.main(AppMain.java:120)

Process finished with exit code 1

Alvast bedankt!

 

[Supersnail]

"panel", "label" en "panel1" zijn null. Ze worden wel aangemaakt in de klasse, maar niet geïnitialiseerd. De initialisatie gebeurt in de methode "initComponenten()", maar deze roep je niet aan.

 

[Azuma]

En wat moet ik dan exact ergens bijvullen ofzo Supersnail?

 

[Supersnail]

Als je boven de regel

maakComponenten();

de regel

initComponenten();

zet krijg je deze foutmelding niet meer.

 

[Azuma]

Dankje Supersnail!!

 

[Supersnail]

Is het gelukt?

 

[Azuma]

Ja je had gelijk. dom foutje van mij . BEDANKT!