Java Swing How to - Update JLabel with Button for values in a List

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Question

We would like to know how to update JLabel with Button for values in a List.

Answer

import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
/*from   ww  w . j  av a2 s  .c  o m*/
import javax.swing.AbstractAction;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;

public class Main {
  List<String> list = new ArrayList<>(Arrays.asList("A",
      "B", "C", "D", "E"));
  int index = list.indexOf("C");
  JLabel label = new JLabel(list.get(index), JLabel.CENTER);

  private void display() {
    JFrame f = new JFrame();
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    f.add(new JButton(new AbstractAction("<Prev") {
      @Override
      public void actionPerformed(ActionEvent e) {
        if (--index < 0) {
          index = list.size() - 1;
        }
        update();
      }
    }), BorderLayout.LINE_START);
    f.add(label);
    f.add(new JButton(new AbstractAction("Next>") {
      @Override
      public void actionPerformed(ActionEvent e) {
        if (++index == list.size()) {
          index = 0;
        }
        update();
      }
    }), BorderLayout.LINE_END);
    f.pack();
    f.setVisible(true);
  }

  private void update() {
    label.setText(list.get(index));
  }

  public static void main(String[] args) {
    new Main().display();
  }
}

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