JLabel的ActionListener
我想学习如何为JLabel编写ActionListener 。 我想制作一个标签，在用户点击标签时为用户打开一个新框架。 也许MouseListener可以工作，但我不知道如何制作它。
我建议使用JTextField而不是JLabel来实现此用途。
基于可设计为可聚焦的组件，它允许ActionListener并且外观和感觉更像是HTML链接。
例如
这就是鼠标hover在第一个链接上时的显示方式。
LinkLabel
/* License - LGPL LinkLabel Using the Desktop Class There are a lot of link labels. This one uses the Java 1.6+ Desktop class for its functionality, and is thereby suitable for applets, applications launched using JWS, and 'standard' (non-JWS) desktop applications. Note that the Desktop class can be used with pre 1.6 JREs. It is available through JDIC. https://jdic.dev.java.net/nonav/documentation/javadoc/jdic/org/jdesktop/jdic/desktop/Desktop.html */ import java.awt.Desktop; import java.awt.Color; import java.awt.Cursor; import java.awt.BorderLayout; import java.awt.GridLayout; import java.awt.event.*; import javax.swing.JTextField; import javax.swing.JPanel; import javax.swing.JOptionPane; import javax.swing.border.MatteBorder; import javax.swing.border.Border; import java.net.URI; import java.io.File; /** A Java 1.6+ LinkLabel that uses the Desktop class for opening the document of interest. The Desktop.browse(URI) method can be invoked from applications, applets and apps. launched using Java Webstart. In the latter two cases, the usual fall-back methods are used for sandboxed apps (see the JavaDocs for further details). While called a 'label', this class actually extends JTextField, to easily allow the component to become focusable using keyboard navigation. To successfully browse to a URI for a local File, the file name must be constructed using a canonical path. @author Andrew Thompson @version 2008/08/23 */ public class LinkLabel // we extend a JTextField, to get a focusable component extends JTextField implements MouseListener, FocusListener, ActionListener { /** The target or href of this link. */ private URI target; public Color standardColor = new Color(0,0,255); public Color hoverColor = new Color(255,0,0); public Color activeColor = new Color(128,0,128); public Color transparent = new Color(0,0,0,0); public boolean underlineVisible = true; private Border activeBorder; private Border hoverBorder; private Border standardBorder; /** Construct a LinkLabel that points to the given target. The URI will be used as the link text.*/ public LinkLabel(URI target) { this( target, target.toString() ); } /** Construct a LinkLabel that points to the given target, and displays the text to the user. */ public LinkLabel(URI target, String text) { super(text); this.target = target; } /* Set the active color for this link (default is purple). */ public void setActiveColor(Color active) { activeColor = active; } /* Set the hover/focused color for this link (default is red). */ public void setHoverColor(Color hover) { hoverColor = hover; } /* Set the standard (non-focused, non-active) color for this link (default is blue). */ public void setStandardColor(Color standard) { standardColor = standard; } /** Determines whether the */ public void setUnderlineVisible(boolean underlineVisible) { this.underlineVisible = underlineVisible; } /* Add the listeners, configure the field to look and act like a link. */ public void init() { this.addMouseListener(this); this.addFocusListener(this); this.addActionListener(this); setToolTipText(target.toString()); if (underlineVisible) { activeBorder = new MatteBorder(0,0,1,0,activeColor); hoverBorder = new MatteBorder(0,0,1,0,hoverColor); standardBorder = new MatteBorder(0,0,1,0,transparent); } else { activeBorder = new MatteBorder(0,0,0,0,activeColor); hoverBorder = new MatteBorder(0,0,0,0,hoverColor); standardBorder = new MatteBorder(0,0,0,0,transparent); } // make it appear like a label/link setEditable(false); setForeground(standardColor); setBorder(standardBorder); setCursor( new Cursor(Cursor.HAND_CURSOR) ); } /** Browse to the target URI using the Desktop.browse(URI) method. For visual indication, change to the active color at method start, and return to the standard color once complete. This is usually so fast that the active color does not appear, but it will take longer if there is a problem finding/loading the browser or URI (eg for a File). */ public void browse() { setForeground(activeColor); setBorder(activeBorder); try { Desktop.getDesktop().browse(target); } catch(Exception e) { e.printStackTrace(); } setForeground(standardColor); setBorder(standardBorder); } /** Browse to the target. */ public void actionPerformed(ActionEvent ae) { browse(); } /** Browse to the target. */ public void mouseClicked(MouseEvent me) { browse(); } /** Set the color to the hover color. */ public void mouseEntered(MouseEvent me) { setForeground(hoverColor); setBorder(hoverBorder); } /** Set the color to the standard color. */ public void mouseExited(MouseEvent me) { setForeground(standardColor); setBorder(standardBorder); } public void mouseReleased(MouseEvent me) {} public void mousePressed(MouseEvent me) {} /** Set the color to the standard color. */ public void focusLost(FocusEvent fe) { setForeground(standardColor); setBorder(standardBorder); } /** Set the color to the hover color. */ public void focusGained(FocusEvent fe) { setForeground(hoverColor); setBorder(hoverBorder); } public static void main(String[] args) throws Exception { JPanel p = new JPanel(new GridLayout(0,1)); File f = new File(".","LinkLabel.java"); /* Filename must be constructed with a canonical path in order to successfully use Desktop.browse(URI)! */ f = new File(f.getCanonicalPath()); URI uriFile = f.toURI(); LinkLabel linkLabelFile = new LinkLabel(uriFile); linkLabelFile.init(); p.add(linkLabelFile); LinkLabel linkLabelWeb = new LinkLabel( new URI("http://sscce.org/"), "SSCCE"); linkLabelWeb.setStandardColor(new Color(0,128,0)); linkLabelWeb.setHoverColor(new Color(222,128,0)); linkLabelWeb.init(); /* This shows a quirk of the LinkLabel class, the size of the text field needs to be constrained to get the underline to appear properly. */ p.add(linkLabelWeb); LinkLabel linkLabelConstrain = new LinkLabel( new URI("http://sdnshare.sun.com/"), "SDN Share"); linkLabelConstrain.init(); /* ..and this shows one way to constrain the size (appropriate for this layout). Similar tricks can be used to ensure the underline does not drop too far *below* the link (think BorderLayout NORTH/SOUTH). The same technique can also be nested further to produce a NORTH+EAST packing (for example). */ JPanel labelConstrain = new JPanel(new BorderLayout()); labelConstrain.add( linkLabelConstrain, BorderLayout.EAST ); p.add(labelConstrain); LinkLabel linkLabelNoUnderline = new LinkLabel( new URI("http://java.net/"), "java.net"); // another way to deal with the underline is to remove it linkLabelNoUnderline.setUnderlineVisible(false); // we can use the methods inherited from JTextField linkLabelNoUnderline. setHorizontalAlignment(JTextField.CENTER); linkLabelNoUnderline.init(); p.add(linkLabelNoUnderline); JOptionPane.showMessageDialog( null, p ); } }