MainClass.java Source code

Introduction

Here is the source code for MainClass.java

Source

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JScrollBar;
import javax.swing.JScrollPane;
import javax.swing.border.LineBorder;

public class MainClass {
    public static void main(String args[]) throws Exception {
        JFrame frame = new JFrame("Cornering Sample");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        JButton button = new JButton("+");

        JLabel bigLabel = new JLabel("A");
        bigLabel.setPreferredSize(new Dimension(400, 400));
        bigLabel.setBorder(new LineBorder(Color.red));

        JScrollPane scrollPane = new JScrollPane(bigLabel);
        scrollPane.setCorner(JScrollPane.UPPER_LEFT_CORNER, button);
        scrollPane.setColumnHeaderView(new JLabel("B"));
        scrollPane.setRowHeaderView(new JLabel("C"));

        ActionListener actionListener = new JScrollPaneToTopAction(scrollPane);
        button.addActionListener(actionListener);

        frame.add(scrollPane, BorderLayout.CENTER);
        frame.setSize(300, 200);
        frame.setVisible(true);
    }

}

class JScrollPaneToTopAction implements ActionListener {
    JScrollPane scrollPane;

    public JScrollPaneToTopAction(JScrollPane scrollPane) {
        if (scrollPane == null) {
            throw new IllegalArgumentException("JScrollPaneToTopAction: null JScrollPane");
        }
        this.scrollPane = scrollPane;
    }

    public void actionPerformed(ActionEvent actionEvent) {
        JScrollBar verticalScrollBar = scrollPane.getVerticalScrollBar();
        JScrollBar horizontalScrollBar = scrollPane.getHorizontalScrollBar();
        verticalScrollBar.setValue(verticalScrollBar.getMinimum());
        horizontalScrollBar.setValue(horizontalScrollBar.getMinimum());
    }
}