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1   /***
2    * Redistribution  and use  in source  and binary  forms, with  or without
3    * modification, are permitted provided  that the following conditions are
4    * met :
5    *
6    * . Redistributions  of  source  code  must  retain  the  above copyright
7    *   notice, this list of conditions and the following disclaimer.
8    *
9    * . Redistributions in  binary form  must reproduce  the above  copyright
10   *   notice, this list of conditions  and the following disclaimer in  the
11   *   documentation and/or other materials provided with the distribution.
12   *
13   * . The name of the author may not be used to endorse or promote products
14   *   derived from this software without specific prior written permission.
15   *
16   * THIS SOFTWARE IS  PROVIDED BY THE  AUTHOR ``AS IS''  AND ANY EXPRESS  OR
17   * IMPLIED  WARRANTIES,  INCLUDING,  BUT   NOT  LIMITED  TO,  THE   IMPLIED
18   * WARRANTIES OF MERCHANTABILITY AND  FITNESS FOR A PARTICULAR  PURPOSE ARE
19   * DISCLAIMED.  IN NO  EVENT SHALL  THE AUTHOR  BE LIABLE  FOR ANY  DIRECT,
20   * INDIRECT,  INCIDENTAL,  SPECIAL,  EXEMPLARY,  OR  CONSEQUENTIAL  DAMAGES
21   * (INCLUDING,  BUT  NOT LIMITED  TO,  PROCUREMENT OF  SUBSTITUTE  GOODS OR
22   * SERVICES;  LOSS  OF USE,  DATA,  OR PROFITS;  OR  BUSINESS INTERRUPTION)
23   * HOWEVER CAUSED  AND ON  ANY THEORY  OF LIABILITY,  WHETHER IN  CONTRACT,
24   * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
25   * ANY  WAY  OUT OF  THE  USE OF  THIS  SOFTWARE, EVEN  IF  ADVISED OF  THE
26   * POSSIBILITY OF SUCH DAMAGE.
27   *
28   * $Id: AboutDialog.java 396 2005-12-31 12:57:52Z mat007 $
29   */
30  
31  package palmed.ui;
32  
33  import javax.microedition.lcdui.Command;
34  import javax.microedition.lcdui.CommandListener;
35  import javax.microedition.lcdui.Display;
36  import javax.microedition.lcdui.Displayable;
37  import javax.microedition.lcdui.Font;
38  import javax.microedition.lcdui.Item;
39  import javax.microedition.lcdui.StringItem;
40  import javax.microedition.midlet.MIDlet;
41  
42  /***
43   * This dialog shows an 'about' box.
44   *
45   * @author Mathieu Champlon
46   * @version $Revision: 396 $ $Date: 2005-12-31 21:57:52 +0900 (sam., 31 déc. 2005) $
47   */
48  public final class AboutDialog extends Dialog implements CommandListener
49  {
50      /***
51       * The number of characters for memory fields.
52       */
53      private static final int NUMBER_OF_DIGITS = 8;
54      /***
55       * The display.
56       */
57      private final Display display_;
58      /***
59       * The displayable to show when closing the dialog.
60       */
61      private final Displayable next_;
62      /***
63       * The item displaying the amount of free memory.
64       */
65      private final StringItem freeMemory_;
66      /***
67       * The item displaying the amount of used memory.
68       */
69      private final StringItem usedMemory_;
70      /***
71       * The item displaying the total amount of memory.
72       */
73      private final StringItem totalMemory_;
74  
75      /***
76       * Create an 'about' dialog.
77       *
78       * @param midlet the midlet to display the information about
79       * @param display the application display
80       * @param next the displayable to show when 'OK' is pressed
81       */
82      public AboutDialog( final MIDlet midlet, final Display display, final Displayable next )
83      {
84          super( "About " + midlet.getAppProperty( "MIDlet-Name" ) );
85          if( display == null )
86              throw new IllegalArgumentException( "parameter 'display' is null" );
87          if( next == null )
88              throw new IllegalArgumentException( "parameter 'next' is null" );
89          display_ = display;
90          next_ = next;
91          appendMessage( midlet.getAppProperty( "MIDlet-Name" ) + " " + midlet.getAppProperty( "MIDlet-Version" ) );
92          append( createUrlItem( midlet.getAppProperty( "MIDlet-Info-URL" ) ) );
93          appendMessage( "Icons by the Tango Project" );
94          append( createUrlItem( "http://tango-project.org" ) );
95          appendMessage( "Memory" );
96          freeMemory_ = appendMessage();
97          usedMemory_ = appendMessage();
98          totalMemory_ = appendMessage();
99          refresh();
100         addCommand( new Command( "Ok", Command.OK, 1 ) );
101         setCommandListener( this );
102     }
103 
104     /***
105      * Refresh informations.
106      *
107      * @return this
108      */
109     public Displayable refresh()
110     {
111         Runtime.getRuntime().gc();
112         refreshFreeMemory();
113         refreshUsedMemory();
114         refreshTotalMemory();
115         return this;
116     }
117 
118     private void refreshFreeMemory()
119     {
120         final String memory = String.valueOf( Runtime.getRuntime().freeMemory() );
121         freeMemory_.setText( format( memory ) + " bytes free" );
122     }
123 
124     private void refreshUsedMemory()
125     {
126         final String memory = String.valueOf( Runtime.getRuntime().totalMemory() - Runtime.getRuntime().freeMemory() );
127         usedMemory_.setText( format( memory ) + " bytes used" );
128     }
129 
130     private void refreshTotalMemory()
131     {
132         final String memory = String.valueOf( Runtime.getRuntime().totalMemory() );
133         totalMemory_.setText( format( memory ) + " bytes total" );
134     }
135 
136     private String format( final String string )
137     {
138         final StringBuffer buffer = new StringBuffer( string );
139         for( int i = 0; i < NUMBER_OF_DIGITS - string.length(); ++i )
140             buffer.insert( 0, ' ' );
141         return buffer.toString();
142     }
143 
144     private StringItem appendMessage()
145     {
146         final StringItem item = new StringItem( null, null );
147         item.setLayout( Item.LAYOUT_NEWLINE_BEFORE );
148         item.setFont( Font.getFont( Font.FACE_SYSTEM, Font.STYLE_PLAIN, Font.SIZE_SMALL ) );
149         append( item );
150         return item;
151     }
152 
153     private Item createUrlItem( final String url )
154     {
155         final StringItem item = new StringItem( null, url, Item.HYPERLINK );
156         item.setLayout( Item.LAYOUT_NEWLINE_BEFORE );
157         return item;
158     }
159 
160     /***
161      * {@inheritDoc}
162      */
163     public void commandAction( final Command command, final Displayable displayable )
164     {
165         display_.setCurrent( next_ );
166     }
167 }