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Thread: passing value and setting it to jlabel text

  1. #1
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    Default passing value and setting it to jlabel text

    This site is really helping a lot of people! I have a simple program that I can't understand why I am getting the NullPointerException each time I try to pass a value from one form to another and setting it up as a text in a label. If I pass the value and do the pritln, I can actually see the result but if I place it in the jlabel as text, that's the time I get the error. Please Help! Thanks! Here is the code to pass the value to the other form.

    [CODE = java]public class Micolocoi extends JApplet {
    private String lblName;

    public JLabel lblTime, lblRem1, lblRem2, lblRem3, lblRem4, lblRem5;
    lblRem1 = new JLabel("0", SwingConstants.CENTER);
    lblRem2 = new JLabel("0", SwingConstants.CENTER);
    lblRem3 = new JLabel("0", SwingConstants.CENTER);
    lblRem4 = new JLabel("0", SwingConstants.CENTER);
    lblRem5 = new JLabel("0", SwingConstants.CENTER);

    public void setRem1(String input) { lblName = input; System.out.println(input); } //TO GET THE VALUE FROM THE OTHER FORM
    public String getRem1() { return lblName; }
    public void setLblRem1(){ lblRem1.setText(getRem1()); } //TO SET UP THE VALUE AS THE TEXT OF THE LABEL
    }
    public static void main(String args[]){

    Micolocoi micolocoi = new Micolocoi();
    JFrame frame = new JFrame("MICOLOCOI");
    Container container = frame.getContentPane();
    container.add(micolocoi);
    frame.setSize(600, 200);
    frame.setResizable(false);
    frame.setLocationRelativeTo(null);


    micolocoi.init();
    micolocoi.start();
    micolocoi.getDateTime();

    frame.setVisible(true);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOS E);

    }
    }


    public class Choice extends JFrame {

    btnPrepaid.addActionListener(new ActionListener() {

    public void actionPerformed(ActionEvent e) {
    selectionAction(e);
    }
    });

    private void selectionAction(ActionEvent evt){
    System.out.println(choice);
    int choice = getChoice();
    boolean bol = true;
    switch (choice) {

    case 1:
    while(bol){
    String str = JOptionPane.showInputDialog(null, "Input minutes ", "ALERT", 1);
    if(str != null && Integer.parseInt(str) != 0){
    JOptionPane.showMessageDialog(null, "Time will run for " +str +" minutes", "ALERT", 1);
    mic.setRem1(str); //THIS IS WHAT I AM TRYING TO PASS TO THE OTHER FORM AND SET IT AS THE TEXT FOR THE LABEL SO I CAN ACTUALLY SUBTRACT 1 EACH MINUTE
    mic.setLblRem1();
    setVisible(false);
    bol = false;
    } else {
    JOptionPane.showMessageDialog(null, "No input given", "ALERT", 1);
    group.clearSelection();
    }
    }
    break;

    case 2:
    while(bol){
    String str = JOptionPane.showInputDialog(null, "Input minutes ", "ALERT", 1);

    if(str != null && Integer.parseInt(str) != 0){
    JOptionPane.showMessageDialog(null, "Time will run for " +str +" minutes", "ALERT", 1);
    System.out.println("dfsadsf");
    setVisible(false);
    bol = false;
    break;
    } else {
    JOptionPane.showMessageDialog(null, "No input given", "ALERT", 1);
    group.clearSelection();
    }
    }
    break;
    }.... [/CODE]


  2. #2
    Super Moderator Norm's Avatar
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    Default Re: passing value and setting it to jlabel text

    Please Edit your post and wrap your code with
    [code=java]
    <YOUR CODE HERE>
    [/code]
    to get highlighting and preserve formatting.

    Also posted at Passing value and setting it to jlabel text - Dev Shed
    If you don't understand my answer, don't ignore it, ask a question.

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