Java JViewport

Swing is a Java GUI (Graphical User Interface) toolkit that includes many components and tools for developing dynamic and user-friendly desktop applications. JViewPoint is majorly used for arranging and displaying large or scrollable content.

What is a JViewPort?

JViewport is mostly used to give a window into a larger view when the content exceeds the available screen area.

The fundamental scrolling model is defined by the JViewport class, which is made to support both logical and pixel-based scrolling. It is widely used within JScrollPane, a container that allows you to add scrollbars to a GUI component when the viewable area is exceeded.

Syntax of JViewPort

public class JViewport extends JComponent implements Accessible

The JViewPort class inherits the properties and attributes of the JComponent class, making it a graphical component for Java Swing applications. It also implements the Accessible interface which improves the accessibility for the users by offering appropriate interactive features.

Constructor of JViewPort

The table provides an overview of all the available constructors present for JViewport() along with their descriptions.

Nested Classes of JViewPort

The table provides an overview of all the available Classes present for JViewport() along with their description.

The nested classes offered by Java JViewPort are inherited from:

• javax.swing.JComponent
• java.awt.Container
• java.awt.Component

Fields of JViewPort

The table provides an overview of all the available Fields present for JViewport() along with their description.

The fields of Java JViewPort are inherited from:

• java.awt.Component
• java.awt.image.ImageObserver
• javax.swing.JComponent

Methods of JViewPort

Following are the methods associated with the JViewPort class along with their detailed explanation:

The methods corresponding to Java JViewPort are inherited from packages like:

• java.awt.Container
• java.awt.Component
• javax.swing.JComponent
• java.lang.Object

Example of Java JViewport

In the given example, the Swing application created by this Java code demonstrates the use of JViewport. It creates a JFrame with a JViewport that has two labels: one labeled "A computer science portal for geeks!" underneath it, and a big one labeled "GeeksforGeeks" centered as the view. This code offers a basic example of how to create a scrollable view inside of a GUI by demonstrating how to define various parameters like font, color, and scroll mode respectively.

// Java Program to demonstrate
// Java JViewport
import java.awt.*;
import javax.swing.*;

// Driver Class
public class Main {
      // main function
    public static void main(String[] args)
    {
        // Create a frame
        JFrame f = new JFrame("JViewport Example");
        // Layout for the frame
        f.setLayout(new BorderLayout());

        // Create a label and set its properties
        JLabel l1 = new JLabel("GeeksforGeeks");
        l1.setFont(new Font("Arial", Font.BOLD, 40));
        l1.setForeground(Color.GREEN);
        l1.setHorizontalAlignment(JLabel.CENTER);

        // Create another label and set its properties
        JLabel l2 = new JLabel(
            "A computer science portal for geeks!");
        l2.setFont(new Font("Arial", Font.PLAIN, 14));

        // Create a JViewport
        JViewport j = new JViewport();
        // Make label l1 as the view of the viewport
        j.setView(l1);
        // Set the view position of the viewport
        j.setViewPosition(new Point(50, 25));
        // Set the size of the viewport
        j.setPreferredSize(new Dimension(350, 200));
        // Add the scrollable properties
        j.setScrollMode(JViewport.SIMPLE_SCROLL_MODE);

        // Create a JPanel
        JPanel p = new JPanel();
        // Add the viewport to the panel
        p.add(j);
        // Add label l2 to the panel
        p.add(l2);

        // Add panel p to the frame f
        f.add(p, BorderLayout.CENTER);
        // Close operation of JFrame
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        // Set the size of the frame
        f.setSize(400, 400);
        // Make the frame visible
        f.setVisible(true);
    }
}

You can execute the code by running the following commands:

Javac Main.java
Java Main

Output: