JSpinner

 

🔄 Java Swing JSpinner – Overview & Example

JSpinner is a Swing component that allows users to select a number or object value from a sequence by clicking up/down arrows or typing.

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✅ Key Features

Method / Property	Description
setModel(SpinnerModel)	Set a value model (number, list, date, etc.)
getValue()	Get current spinner value
setValue(Object)	Set spinner value
addChangeListener(...)	Listen to value changes

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📦 Types of Spinner Models

Spinner Model	Description
SpinnerNumberModel	Integer/double values
SpinnerListModel	List of strings or objects
SpinnerDateModel	Dates (with min/max & step size)

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✅ Example 1: Spinner with Numbers

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

public class NumberSpinnerExample {
    public static void main(String[] args) {
        JFrame frame = new JFrame("JSpinner Number Example");
        frame.setSize(300, 100);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        SpinnerNumberModel model = new SpinnerNumberModel(5, 0, 10, 1);
        JSpinner spinner = new JSpinner(model);

        frame.setLayout(new FlowLayout());
        frame.add(new JLabel("Select Number:"));
        frame.add(spinner);

        frame.setVisible(true);
    }
}

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✅ Example 2: Spinner with List of Strings

String[] fruits = {"Apple", "Banana", "Mango", "Orange"};
JSpinner spinner = new JSpinner(new SpinnerListModel(fruits));

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✅ Example 3: Spinner with Dates

JSpinner dateSpinner = new JSpinner(new SpinnerDateModel());
JSpinner.DateEditor editor = new JSpinner.DateEditor(dateSpinner, "dd/MM/yyyy");
dateSpinner.setEditor(editor);

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🧠 Useful Tips

• Use spinner.getValue() to retrieve the selected value.

• Use custom editors (JSpinner.NumberEditor, JSpinner.DateEditor) for better display.

• Combine with ChangeListener to track changes:

spinner.addChangeListener(e -> {
    System.out.println("Selected: " + spinner.getValue());
});

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Would you like an example combining JSpinner with JLabel to show live value updates?