What is the best way to add a hyperlink in a JLabel? I can get the view using html tags, but how to open the browser when the user clicks on it?
What is the best way to add a hyperlink in a JLabel? I can get the view using html tags, but how to open the browser when the user clicks on it?
You can do this using a JLabel, but an alternative would be to style a JButton. That way, you don't have to worry about accessibility and can just fire events using an ActionListener.
public static void main(String[] args) throws URISyntaxException {
final URI uri = new URI("http://java.sun.com");
class OpenUrlAction implements ActionListener {
@Override public void actionPerformed(ActionEvent e) {
open(uri);
}
}
JFrame frame = new JFrame("Links");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(100, 400);
Container container = frame.getContentPane();
container.setLayout(new GridBagLayout());
JButton button = new JButton();
button.setText("<HTML>Click the <FONT color=\"#000099\"><U>link</U></FONT>"
+ " to go to the Java website.</HTML>");
button.setHorizontalAlignment(SwingConstants.LEFT);
button.setBorderPainted(false);
button.setOpaque(false);
button.setBackground(Color.WHITE);
button.setToolTipText(uri.toString());
button.addActionListener(new OpenUrlAction());
container.add(button);
frame.setVisible(true);
}
private static void open(URI uri) {
if (Desktop.isDesktopSupported()) {
try {
Desktop.getDesktop().browse(uri);
} catch (IOException e) { /* TODO: error handling */ }
} else { /* TODO: error handling */ }
}
Update I've tidied up the SwingLink class further and added more features; an up-to-date copy of it can be found here: https://bitbucket.org/dimo414/jgrep/src/tip/src/grep/SwingLink.java
@McDowell's answer is great, but there's several things that could be improved upon. Notably text other than the hyperlink is clickable and it still looks like a button even though some of the styling has been changed/hidden. While accessibility is important, a coherent UI is as well.
So I put together a class extending JLabel based on McDowell's code. It's self-contained, handles errors properly, and feels more like a link:
public class SwingLink extends JLabel {
private static final long serialVersionUID = 8273875024682878518L;
private String text;
private URI uri;
public SwingLink(String text, URI uri){
super();
setup(text,uri);
}
public SwingLink(String text, String uri){
super();
setup(text,URI.create(uri));
}
public void setup(String t, URI u){
text = t;
uri = u;
setText(text);
setToolTipText(uri.toString());
addMouseListener(new MouseAdapter() {
public void mouseClicked(MouseEvent e) {
open(uri);
}
public void mouseEntered(MouseEvent e) {
setText(text,false);
}
public void mouseExited(MouseEvent e) {
setText(text,true);
}
});
}
@Override
public void setText(String text){
setText(text,true);
}
public void setText(String text, boolean ul){
String link = ul ? "<u>"+text+"</u>" : text;
super.setText("<html><span style=\"color: #000099;\">"+
link+"</span></html>");
this.text = text;
}
public String getRawText(){
return text;
}
private static void open(URI uri) {
if (Desktop.isDesktopSupported()) {
Desktop desktop = Desktop.getDesktop();
try {
desktop.browse(uri);
} catch (IOException e) {
JOptionPane.showMessageDialog(null,
"Failed to launch the link, your computer is likely misconfigured.",
"Cannot Launch Link",JOptionPane.WARNING_MESSAGE);
}
} else {
JOptionPane.showMessageDialog(null,
"Java is not able to launch links on your computer.",
"Cannot Launch Link", JOptionPane.WARNING_MESSAGE);
}
}
}
You could also, for instance, change the link color to purple after being clicked, if that seemed useful. It's all self contained, you simply call:
SwingLink link = new SwingLink("Java", "http://java.sun.com");
mainPanel.add(link);
If <a href="link"> doesn't work, then:
Have a look at java.awt.Desktop API for opening a link using the default browser (this API is available only from Java6).