toolkit/test/accessibility/HelpWindow.java

   1 import javax.swing.JFrame;
   2 import javax.swing.JScrollPane;
   3 import javax.swing.JEditorPane;
   4 import javax.swing.JButton;
   5 import java.net.URL;
   6 import javax.swing.event.HyperlinkListener;
   7 import javax.swing.event.HyperlinkEvent;
   8 import java.net.MalformedURLException;
   9 import java.io.IOException;
  10 import java.io.File;
  11 import java.awt.event.WindowAdapter;
  12 import java.awt.event.WindowEvent;
  13 import java.awt.GridBagLayout;
  14 import java.awt.GridBagConstraints;
  15 import java.awt.event.ActionListener;
  16 import java.util.LinkedList;
  17
  18 class HelpWindow
  19     implements ActionListener
  20 {
  21     public static synchronized HelpWindow Instance ()
  22     {
  23         if (maInstance == null)
  24             maInstance = new HelpWindow();
  25         return maInstance;
  26     }
  27
  28     public void loadFile (String sFilename)
  29     {
  30         File aFile = new File (sFilename);
  31         try
  32         {
  33             loadURL (aFile.toURL());
  34         }
  35         catch (MalformedURLException e)
  36         {
  37             e.printStackTrace (System.err);
  38         }
  39     }
  40     public void loadURL (String sURL)
  41     {
  42         try
  43         {
  44             loadURL (new URL (sURL));
  45         }
  46         catch (MalformedURLException e)
  47         {
  48             e.printStackTrace (System.err);
  49         }
  50     }
  51
  52
  53
  54
  55     public void loadURL (URL aURL)
  56     {
  57         maHistory.addLast (aURL);
  58         selectHistoryPage (maHistory.size()-1);
  59         maFrame.toFront ();
  60     }
  61
  62
  63
  64
  65     private HelpWindow ()
  66     {
  67         try
  68         {
  69             maCurrentHistoryEntry = -1;
  70             maHistory = new LinkedList();
  71
  72             maFrame = new JFrame ();
  73             maFrame.addWindowListener (new WindowAdapter ()
  74                 {
  75                     public void windowClosing (WindowEvent e)
  76                     {
  77                         maInstance = null;
  78                     }
  79                 });
  80             maContent = createContentWidget();
  81
  82             maFrame.getContentPane().setLayout (new GridBagLayout());
  83             GridBagConstraints aConstraints = new GridBagConstraints ();
  84             aConstraints.gridx = 0;
  85             aConstraints.gridy = 0;
  86             aConstraints.gridwidth = 3;
  87             aConstraints.weightx = 1;
  88             aConstraints.weighty = 1;
  89             aConstraints.fill = GridBagConstraints.BOTH;
  90             maFrame.getContentPane().add (new JScrollPane (maContent), aConstraints);
  91
  92             aConstraints = new GridBagConstraints();
  93             aConstraints.gridx = 0;
  94             aConstraints.gridy = 1;
  95             maPrevButton = new JButton ("Prev");
  96             maFrame.getContentPane().add (maPrevButton, aConstraints);
  97             maPrevButton.addActionListener (this);
  98
  99             aConstraints = new GridBagConstraints();
 100             aConstraints.gridx = 1;
 101             aConstraints.gridy = 1;
 102             maNextButton = new JButton ("Next");
 103             maFrame.getContentPane().add (maNextButton, aConstraints);
 104             maNextButton.addActionListener (this);
 105
 106             aConstraints = new GridBagConstraints();
 107             aConstraints.gridx = 2;
 108             aConstraints.gridy = 1;
 109             aConstraints.anchor = GridBagConstraints.EAST;
 110             JButton aButton = new JButton ("Close");
 111             maFrame.getContentPane().add (aButton, aConstraints);
 112             aButton.addActionListener (this);
 113
 114             maFrame.setSize (600,400);
 115             maFrame.setVisible (true);
 116         }
 117         catch (Exception e)
 118         {}
 119     }
 120
 121     public void actionPerformed (java.awt.event.ActionEvent e)
 122     {
 123         if (e.getActionCommand().equals("Prev"))
 124         {
 125             selectHistoryPage (maCurrentHistoryEntry - 1);
 126         }
 127         else if (e.getActionCommand().equals("Next"))
 128         {
 129             selectHistoryPage (maCurrentHistoryEntry + 1);
 130         }
 131         else if (e.getActionCommand().equals("Close"))
 132         {
 133             maFrame.dispose ();
 134             maInstance = null;
 135         }
 136     }
 137
 138     private JEditorPane createContentWidget ()
 139     {
 140         JEditorPane aContent = new JEditorPane ();
 141         aContent.setEditable (false);
 142         aContent.addHyperlinkListener (new HyperlinkListener()
 143             {
 144                 public void hyperlinkUpdate (HyperlinkEvent e)
 145                 {
 146                     if (e.getEventType() == HyperlinkEvent.EventType.ACTIVATED)
 147                         HelpWindow.Instance().loadURL (e.getURL());
 148                 }
 149             });
 150         return aContent;
 151     }
 152
 153     private void selectHistoryPage (int i)
 154     {
 155         if (i < 0)
 156             i = 0;
 157         else if (i >= maHistory.size()-1)
 158             i = maHistory.size()-1;
 159         if (i != maCurrentHistoryEntry)
 160         {
 161             URL aURL = (URL)maHistory.get (i);
 162             try
 163             {
 164                 maContent.setPage (aURL);
 165             }
 166             catch (java.io.IOException ex)
 167             {
 168                 ex.printStackTrace(System.err);
 169             }
 170
 171             maCurrentHistoryEntry = i;
 172         }
 173
 174         maPrevButton.setEnabled (maCurrentHistoryEntry > 0);
 175         maNextButton.setEnabled (maCurrentHistoryEntry < maHistory.size()-1);
 176     }
 177
 178     private static HelpWindow maInstance = null;
 179     private JFrame maFrame;
 180     private JEditorPane maContent;
 181     private LinkedList maHistory;
 182     private int maCurrentHistoryEntry;
 183     private JButton maPrevButton;
 184     private JButton maNextButton;
 185 }