01: /*
02: *
03: *
04: * Copyright 1990-2007 Sun Microsystems, Inc. All Rights Reserved.
05: * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
06: *
07: * This program is free software; you can redistribute it and/or
08: * modify it under the terms of the GNU General Public License version
09: * 2 only, as published by the Free Software Foundation.
10: *
11: * This program is distributed in the hope that it will be useful, but
12: * WITHOUT ANY WARRANTY; without even the implied warranty of
13: * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14: * General Public License version 2 for more details (a copy is
15: * included at /legal/license.txt).
16: *
17: * You should have received a copy of the GNU General Public License
18: * version 2 along with this work; if not, write to the Free Software
19: * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
20: * 02110-1301 USA
21: *
22: * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
23: * Clara, CA 95054 or visit www.sun.com if you need additional
24: * information or have any questions.
25: */
26:
27: package javax.microedition.lcdui;
28:
29: /**
30: * The common superclass of all high-level user interface classes. The
31: * contents displayed and their interaction with the user are defined by
32: * subclasses.
33: *
34: * <P>Using subclass-defined methods, the application may change the contents
35: * of a <code>Screen</code> object while it is shown to the user. If
36: * this occurs, and the
37: * <code>Screen</code> object is visible, the display will be updated
38: * automatically. That
39: * is, the implementation will refresh the display in a timely fashion without
40: * waiting for any further action by the application. For example, suppose a
41: * <code>List</code> object is currently displayed, and every element
42: * of the <code>List</code> is
43: * visible. If the application inserts a new element at the beginning of the
44: * <code>List</code>, it is displayed immediately, and the other
45: * elements will be
46: * rearranged appropriately. There is no need for the application to call
47: * another method to refresh the display.</P>
48: *
49: * <P>It is recommended that applications change the contents of a
50: * <code>Screen</code> only
51: * while it is not visible (that is, while another
52: * <code>Displayable</code> is current).
53: * Changing the contents of a <code>Screen</code> while it is visible
54: * may result in
55: * performance problems on some devices, and it may also be confusing if the
56: * <code>Screen's</code> contents changes while the user is
57: * interacting with it.</P>
58: *
59: * <P>In MIDP the four <code>Screen</code> methods that defined
60: * read/write ticker and
61: * title properties were moved to <code>Displayable</code>,
62: * <code>Screen's</code> superclass. The
63: * semantics of these methods have not changed.</P>
64: *
65: * @since MIDP 1.0
66: */
67: public abstract class Screen extends Displayable {
68:
69: /**
70: * Creates a new Screen object with the given title and with no ticker.
71: *
72: * @param title the Screen's title, or null for no title
73: */
74: Screen(String title) {
75: super(title);
76: }
77: }
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