When a JTextField reaches a certain amount of characters it moves onto the next one

Question

I am making a gift code app and i wanted to know if there was a way to make the TextField your typing in move to the next TextField when you reach a certain amount of characters. So if there were 4 textfields next to each other when i fill the first one with 4 characters instead of hitting tab it moves on to the next jtextfield and so on till it reaches the end

do you know how to detect when text area has 4 characters ? do you know how to focus a textarea programmatically ? then you can do it .can you show your codes ? — Madhawa Priyashantha, Apr 10 '16 at 02:56
No i do not, and what code would you like? All it is is JTextField textField = new JTextField(3); And then i add it to the JPanel. — Bill Nye, Apr 10 '16 at 02:58
here is 2 http://stackoverflow.com/questions/6723257/how-to-set-focus-on-jtextfield and http://stackoverflow.com/questions/30582795/how-to-get-the-number-of-character-in-a-jtextarea — Madhawa Priyashantha, Apr 10 '16 at 02:59
This concept is demonstrated [here](http://stackoverflow.com/questions/25477999/jtextarea-filters-and-or-inputs-of-time-000000-java/25496932#25496932) — MadProgrammer, Apr 10 '16 at 05:32

score 2 · Accepted Answer · edited May 23 '17 at 11:50

What you're basically asking can be easily achieved by using a DocumentListener, for example...

public class MoveFocusForwardHandler implements DocumentListener {

    private int maxLength;

    public MoveFocusForwardHandler(int maxLength) {
        this.maxLength = maxLength;
    }

    public int getMaxLength() {
        return maxLength;
    }

    @Override
    public void insertUpdate(DocumentEvent e) {
        documentChanged(e);
    }

    @Override
    public void changedUpdate(DocumentEvent e) {
        documentChanged(e);
    }

    @Override
    public void removeUpdate(DocumentEvent e) {
        documentChanged(e);
    }

    protected void documentChanged(DocumentEvent e) {
        if (getMaxLength() > 0) {
            if (e.getDocument().getLength() >= getMaxLength()) {
                KeyboardFocusManager.getCurrentKeyboardFocusManager().focusNextComponent();
            }
        }
    }

}

Which is demonstrated here

When a JTextField reaches a certain amount of characters it moves onto the next one

1 Answers1