Get value from JtextField to another class

Question

Im trying to get jTextField value in another class but always get error null exception. Here is my code :

Class Main :

public class FormTambahDoc extends javax.swing.JFrame {
    Utility utility;

    public FormTambahDoc() {
        initComponents();
        utility = new Utility();
        setButton();
    }

    public  String gettextIdentitasPengguna() {
        return textIdentitasPengguna.getText();
    }

     private void setButton() {
        btnSimpan.addActionListener(new ActionListener() {@Override
        public void actionPerformed(ActionEvent e) { utility.cek();} });
    }

  }

Class another:

public class Utility {

FormTambahDoc formTambahDoc;
//FileJpaController controller;


public  void cek()
{

   String inputText = formTambahDoc.gettextIdentitasPengguna();
   System.out.println(inputText);
   //return `Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException`


}

}

What's wrong in this code ?

Have you intialized your variable `formTambahDoc`? Change the third line to `FormTambahDoc formTambahDoc = new FormTambahDoc();` — Sergiy Medvynskyy, May 28 '15 at 07:33
im already try it but when im changing textIdentitasPengguna value on the GUI the output is still the default value so that not what i expected — navotera, May 28 '15 at 07:39
Can you add some more code. From the code snippet it is not clear what is relation between 2 classes. — Anton Krosnev, May 28 '15 at 07:54
this is the complete code hope u can help @AntonK. http://pastebin.com/UkvVSTpK — navotera, May 28 '15 at 08:00
when the code is running the compiler become hang, the error is something like stackoverflow. sorry that what i got, i forget to copy that error here @SergiyMedvynskyy — navotera, May 28 '15 at 08:17

score 1 · Answer 1 · answered May 28 '15 at 07:33

1

You should create instance of FormTambahDoc before you ca use it: FormTambahDoc formTambahDoc = new FormTambahDoc(); or get the instance from somewhere. Otherwise formTambahDoc will always be null. Check again your AWT tutorial.

answered May 28 '15 at 07:33

Anton Krosnev

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im already try it but when im changing _textIdentitasPengguna_ value on the GUI the output is still the default value – navotera May 28 '15 at 07:37

score 0 · Answer 2 · answered May 28 '15 at 08:43

Try following

public class FormTambahDoc extends javax.swing.JFrame {
    Utility utility;

    public FormTambahDoc() {
        initComponents();
        utility = new Utility(this);
        setButton();
    }

    public  String gettextIdentitasPengguna() {
        return textIdentitasPengguna.getText();
    }

     private void setButton() {
        btnSimpan.addActionListener(new ActionListener() {@Override
        public void actionPerformed(ActionEvent e) { utility.cek();} });
    }

}

public class Utility {

    FormTambahDoc formTambahDoc;
    //FileJpaController controller;
    public Utility(FormTambahDoc aForm) {
        formTambahDoc = aForm;
    }

    public  void cek()
    {

       String inputText = formTambahDoc.gettextIdentitasPengguna();
       System.out.println(inputText);
       //return `Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException`


    }

}

Exception in thread "main" java.lang.RuntimeException: Uncompilable source code - constructor Utility in class sharesystem.digital_file.controller.Utility cannot be applied to given types; required: sharesystem.digital_file.view.FormTambahDoc found: no arguments reason: actual and formal argument lists differ in length — navotera, May 29 '15 at 01:19

Get value from JtextField to another class

2 Answers2