diff options
Diffstat (limited to 'odk/examples/DevelopersGuide/Accessibility/MessageArea.java')
-rw-r--r-- | odk/examples/DevelopersGuide/Accessibility/MessageArea.java | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/odk/examples/DevelopersGuide/Accessibility/MessageArea.java b/odk/examples/DevelopersGuide/Accessibility/MessageArea.java new file mode 100644 index 000000000000..9f3280a591a1 --- /dev/null +++ b/odk/examples/DevelopersGuide/Accessibility/MessageArea.java @@ -0,0 +1,133 @@ +/************************************************************************* + * + * The Contents of this file are made available subject to the terms of + * the BSD license. + * + * Copyright 2000, 2010 Oracle and/or its affiliates. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of Sun Microsystems, Inc. nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS + * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND + * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR + * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE + * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + *************************************************************************/ + +import java.awt.Font; +import java.awt.Rectangle; +import java.awt.Color; +import java.awt.Graphics; +import javax.swing.JScrollPane; +import javax.swing.JTextArea; +import javax.swing.JScrollBar; + + + +/** A message area displays text in a scrollable text widget. It is a + singleton. Other objects can access it directly to display messages. +*/ +public class MessageArea + extends JScrollPane +{ + public static synchronized MessageArea Instance () + { + if (saInstance == null) + saInstance = new MessageArea (); + return saInstance; + } + + + + + /** Create a new message area. This method is private because the class is + a singleton and may therefore not be instanciated from the outside. + */ + private MessageArea () + { + maText = new JTextArea(); + maText.setBackground (new Color (255,250,240)); + maText.setFont (new Font ("Helvetica", Font.PLAIN, 9)); + setViewportView (maText); + setVerticalScrollBarPolicy (JScrollPane.VERTICAL_SCROLLBAR_ALWAYS); + setHorizontalScrollBarPolicy (JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS); + + printMessage ( + "class path is " + System.getProperty ("java.class.path") + "\n"); + } + + + + + /** Show the given string at the end of the message area and scroll to make + it visible. + */ + public static synchronized void print (String aMessage) + { + Instance().printMessage(aMessage); + } + + + + + /** Show the given string at the end of the message area and scroll to make + it visible. + */ + public static void println (String aMessage) + { + Instance().printMessage (aMessage+"\n"); + } + + + public void paintComponent (Graphics g) + { + // Synchronize with the graphics object to prevent paint problems. + // Remember that this is not done by Swing itself. + synchronized (g) + { + JScrollBar sb = getVerticalScrollBar(); + if (sb != null) + { + int nScrollBarValue = sb.getMaximum() - sb.getVisibleAmount() - 1; + sb.setValue (nScrollBarValue); + } + super.paintComponent (g); + } + } + + + + + /** Append the given string to the end of the text and scroll so that it + becomes visible. This is an internal method. Use one of the static + and public ones. + */ + private synchronized void printMessage (String aMessage) + { + maText.append (aMessage); + } + + + + + private static MessageArea saInstance = null; + private JTextArea maText; +} |