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Thread: Applet array paint/print question

  1. #1
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    Default Applet array paint/print question

    Hi,

    How do I paint or print an multi-array in applets?



    Here is my code:

    import java.awt.Graphics;
    import javax.swing.*;
    import java.applet.*;

    public class Applettest extends JApplet {

    public void init() {

    int Choice = 0;

    String userChoice = JOptionPane.showInputDialog("Enter a number, 0 to 2");
    Choice = Integer.parseInt(userChoice);
    paint(null,Choice);

    }

    public void paint(Graphics g, int testPass) {

    String Multi[][]={{"Line 1","Line 2","Line 3"},{"Line 4","Line 5","Line 6"},{"Line 7","Line 8","Line 9"}};

    g.drawString(Multi[testPass][testPass], 10,10);


    }
    }

    My error:
    java.lang.NullPointerException
    at applets.Applettest.paint(Applettest.java…
    at applets.Applettest.init(Applettest.java:…
    at sun.applet.AppletPanel.run(AppletPanel.j…
    at java.lang.Thread.run(Thread.java:722)


  2. #2
    Super Moderator Norm's Avatar
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    Default Re: Applet array paint/print question

    java.lang.NullPointerException
    at applets.Applettest.paint(Applettest.java…
    What variable is null? Your error message text has left off the line number where the error occurred.

    paint(null,Choice);
    Why do you call the paint() method with a null value?

    If you want to override the paint method, You need to read the API doc for the paint() method to see how to code it.

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