HelpIcon.java

package net.hearthstats.ui;

import javax.imageio.ImageIO;
import javax.swing.*;
import java.awt.*;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.net.URI;
import java.net.URISyntaxException;

/**
 * A simple help icon that can be clicked to browse to the given URL.
 */
public class HelpIcon extends scala.swing.Label {

  private static final long serialVersionUID = 2l;
  private final ImageIcon normalIcon;
  private final ImageIcon hoverIcon;


  public HelpIcon(final String url, String tooltip) {
    BufferedImage normalImage = null;
    BufferedImage hoverImage = null;
    try {
      normalImage = ImageIO.read(getClass().getResource("/images/help-normal.png"));
      hoverImage = ImageIO.read(getClass().getResource("/images/help-hover.png"));
    } catch (IOException e) {
      throw new RuntimeException("Unable to read help icons", e);
    }
    normalIcon = new ImageIcon(normalImage);
    hoverIcon = new ImageIcon(hoverImage);

    normalIcon.setDescription("Help");
    hoverIcon.setDescription("Help");

    tooltip_$eq(tooltip);

    icon_$eq(normalIcon);

    peer().addMouseListener(new MouseAdapter() {
      @Override
      public void mouseClicked(MouseEvent e) {
        if (Desktop.isDesktopSupported()) {
          Desktop d = Desktop.getDesktop();
          try {
            d.browse(new URI(url));
          } catch (IOException e1) {
            e1.printStackTrace();
          } catch (URISyntaxException e1) {
            e1.printStackTrace();
          }
        }
      }

      @Override
      public void mouseEntered(MouseEvent e) {
        icon_$eq(hoverIcon);
        cursor_$eq(Cursor.getPredefinedCursor(Cursor.HAND_CURSOR));
      }

      @Override
      public void mouseExited(MouseEvent e) {
        cursor_$eq(Cursor.getDefaultCursor());
        icon_$eq(normalIcon);
      }
    });
  }

}