1 /*
2 * Copyright (c) 2010, 2014, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package javafx.scene.control;
27
28 import javafx.geometry.Pos;
29
30 import com.sun.javafx.scene.control.skin.RadioButtonSkin;
31
32 import javafx.beans.value.WritableValue;
33 import javafx.css.StyleableProperty;
34 import javafx.scene.AccessibleAttribute;
35 import javafx.scene.AccessibleRole;
36
37 /**
38 * <p>RadioButtons create a series of items where only one item can be
39 * selected. RadioButtons are a specialized {@link ToggleButton}.
40 * When a RadioButton is pressed and released a {@link javafx.event.ActionEvent}
41 * is sent. Your application can perform some action based
42 * on this event by implementing an {@link javafx.event.EventHandler} to
43 * process the {@link javafx.event.ActionEvent}.</p>
44 *
45 * <p>
46 * Only one RadioButton can be selected when placed in a {@link ToggleGroup}.
47 * Clicking on a selected RadioButton will have no effect. A RadioButton that is not
48 * in a ToggleGroup can be selected and unselected. By default a RadioButton is
49 * not in a ToggleGroup. Calling {@code ToggleGroup.getSelectedToggle()}
50 * will return you the RadioButton that has been selected.
51 * </p>
52 *
53 * <pre>
54 * <code>
55 * ToggleGroup group = new ToggleGroup();
56 * RadioButton button1 = new RadioButton("select first");
57 * button1.setToggleGroup(group);
58 * button1.setSelected(true);
59 * RadioButton button2 = new RadioButton("select second");
60 * button2.setToggleGroup(group);
61 * </code>
62 * </pre>
63 * @since JavaFX 2.0
64 */
65 public class RadioButton extends ToggleButton {
66
67 /***************************************************************************
68 * *
69 * Constructors *
70 * *
71 **************************************************************************/
72
73 /**
74 * Creates a radio button with an empty string for its label.
75 */
76 public RadioButton() {
77 initialize();
78 }
79
80 /**
81 * Creates a radio button with the specified text as its label.
82 *
83 * @param text A text string for its label.
84 */
85 public RadioButton(String text) {
86 setText(text);
87 initialize();
88 }
89
90 private void initialize() {
91 getStyleClass().setAll(DEFAULT_STYLE_CLASS);
92 setAccessibleRole(AccessibleRole.RADIO_BUTTON);
93 // alignment is styleable through css. Calling setAlignment
94 // makes it look to css like the user set the value and css will not
95 // override. Initializing alignment by calling set on the
96 // CssMetaData ensures that css will be able to override the value.
97 ((StyleableProperty<Pos>)(WritableValue<Pos>)alignmentProperty()).applyStyle(null, Pos.CENTER_LEFT);
98 }
99
100 /***************************************************************************
101 * *
102 * Methods *
103 * *
104 **************************************************************************/
105
106 /**
107 * Toggles the state of the radio button if and only if the RadioButton
108 * has not already selected or is not part of a {@link ToggleGroup}.
109 */
110 @Override public void fire() {
111 // we don't toggle from selected to not selected if part of a group
112 if (getToggleGroup() == null || !isSelected()) {
113 super.fire();
114 }
115 }
116
117 /** {@inheritDoc} */
118 @Override protected Skin<?> createDefaultSkin() {
119 return new RadioButtonSkin(this);
120 }
121
122
123 /***************************************************************************
124 * *
125 * Stylesheet Handling *
126 * *
127 **************************************************************************/
128
129 private static final String DEFAULT_STYLE_CLASS = "radio-button";
130
131 /**
132 * Labeled return CENTER_LEFT for alignment, but ToggleButton returns
133 * CENTER. RadioButton also returns CENTER_LEFT so we have to override
134 * the override in ToggleButton.
135 * @treatAsPrivate implementation detail
136 */
137 @Deprecated @Override
138 protected Pos impl_cssGetAlignmentInitialValue() {
139 return Pos.CENTER_LEFT;
140 }
141
142
143 /***************************************************************************
144 * *
145 * Accessibility handling *
146 * *
147 **************************************************************************/
148
149 @Override
150 public Object queryAccessibleAttribute(AccessibleAttribute attribute, Object... parameters) {
151 switch (attribute) {
152 case SELECTED: return isSelected();
153 default: return super.queryAccessibleAttribute(attribute, parameters);
154 }
155 }
156 }