530b9f9f16864df5eb0f08e5b79fe68f0f0aeb6f
[jvcard.git] / src / com / googlecode / lanterna / gui2 / CheckBoxList.java
1 /*
2 * This file is part of lanterna (http://code.google.com/p/lanterna/).
3 *
4 * lanterna is free software: you can redistribute it and/or modify
5 * it under the terms of the GNU Lesser General Public License as published by
6 * the Free Software Foundation, either version 3 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU Lesser General Public License for more details.
13 *
14 * You should have received a copy of the GNU Lesser General Public License
15 * along with this program. If not, see <http://www.gnu.org/licenses/>.
16 *
17 * Copyright (C) 2010-2015 Martin
18 */
19 package com.googlecode.lanterna.gui2;
20
21 import com.googlecode.lanterna.TerminalSize;
22 import com.googlecode.lanterna.input.KeyStroke;
23 import com.googlecode.lanterna.input.KeyType;
24
25 import java.util.ArrayList;
26 import java.util.List;
27 import java.util.concurrent.CopyOnWriteArrayList;
28
29 /**
30 * This is a list box implementation where each item has its own checked state that can be toggled on and off
31 * @author Martin
32 */
33 public class CheckBoxList<V> extends AbstractListBox<V, CheckBoxList<V>> {
34 /**
35 * Listener interface that can be attached to the {@code CheckBoxList} in order to be notified on user actions
36 */
37 public interface Listener {
38 /**
39 * Called by the {@code CheckBoxList} when the user changes the toggle state of one item
40 * @param itemIndex Index of the item that was toggled
41 * @param checked If the state of the item is now checked, this will be {@code true}, otherwise {@code false}
42 */
43 void onStatusChanged(int itemIndex, boolean checked);
44 }
45
46 private final List<Listener> listeners;
47 private final List<Boolean> itemStatus;
48
49 /**
50 * Creates a new {@code CheckBoxList} that is initially empty and has no hardcoded preferred size, so it will
51 * attempt to be as big as necessary to draw all items.
52 */
53 public CheckBoxList() {
54 this(null);
55 }
56
57 /**
58 * Creates a new {@code CheckBoxList} that is initially empty and has a pre-defined size that it will request. If
59 * there are more items that can fit in this size, the list box will use scrollbars.
60 * @param preferredSize Size the list box should request, no matter how many items it contains
61 */
62 public CheckBoxList(TerminalSize preferredSize) {
63 super(preferredSize);
64 this.listeners = new CopyOnWriteArrayList<Listener>();
65 this.itemStatus = new ArrayList<Boolean>();
66 }
67
68 @Override
69 protected ListItemRenderer<V,CheckBoxList<V>> createDefaultListItemRenderer() {
70 return new CheckBoxListItemRenderer<V>();
71 }
72
73 @Override
74 public synchronized CheckBoxList<V> clearItems() {
75 itemStatus.clear();
76 return super.clearItems();
77 }
78
79 @Override
80 public CheckBoxList<V> addItem(V object) {
81 return addItem(object, false);
82 }
83
84 /**
85 * Adds an item to the checkbox list with an explicit checked status
86 * @param object Object to add to the list
87 * @param checkedState If <code>true</code>, the new item will be initially checked
88 * @return Itself
89 */
90 public synchronized CheckBoxList<V> addItem(V object, boolean checkedState) {
91 itemStatus.add(checkedState);
92 return super.addItem(object);
93 }
94
95 /**
96 * Checks if a particular item is part of the check box list and returns a boolean value depending on the toggle
97 * state of the item.
98 * @param object Object to check the status of
99 * @return If the item wasn't found in the list box, {@code null} is returned, otherwise {@code true} or
100 * {@code false} depending on checked state of the item
101 */
102 public synchronized Boolean isChecked(V object) {
103 if(indexOf(object) == -1)
104 return null;
105
106 return itemStatus.get(indexOf(object));
107 }
108
109 /**
110 * Checks if a particular item is part of the check box list and returns a boolean value depending on the toggle
111 * state of the item.
112 * @param index Index of the item to check the status of
113 * @return If the index was not valid in the list box, {@code null} is returned, otherwise {@code true} or
114 * {@code false} depending on checked state of the item at that index
115 */
116 public synchronized Boolean isChecked(int index) {
117 if(index < 0 || index >= itemStatus.size())
118 return null;
119
120 return itemStatus.get(index);
121 }
122
123 /**
124 * Programmatically sets the checked state of an item in the list box
125 * @param object Object to set the checked state of
126 * @param checked If {@code true}, then the item is set to checked, otherwise not
127 * @return Itself
128 */
129 public synchronized CheckBoxList<V> setChecked(V object, boolean checked) {
130 int index = indexOf(object);
131 if(index != -1) {
132 setChecked(index, checked);
133 }
134 return self();
135 }
136
137 private void setChecked(final int index, final boolean checked) {
138 itemStatus.set(index, checked);
139 runOnGUIThreadIfExistsOtherwiseRunDirect(new Runnable() {
140 @Override
141 public void run() {
142 for(Listener listener: listeners) {
143 listener.onStatusChanged(index, checked);
144 }
145 }
146 });
147 }
148
149 /**
150 * Returns all the items in the list box that have checked state, as a list
151 * @return List of all items in the list box that has checked state on
152 */
153 public synchronized List<V> getCheckedItems() {
154 List<V> result = new ArrayList<V>();
155 for(int i = 0; i < itemStatus.size(); i++) {
156 if(itemStatus.get(i)) {
157 result.add(getItemAt(i));
158 }
159 }
160 return result;
161 }
162
163 /**
164 * Adds a new listener to the {@code CheckBoxList} that will be called on certain user actions
165 * @param listener Listener to attach to this {@code CheckBoxList}
166 * @return Itself
167 */
168 public synchronized CheckBoxList<V> addListener(Listener listener) {
169 if(listener != null && !listeners.contains(listener)) {
170 listeners.add(listener);
171 }
172 return this;
173 }
174
175 /**
176 * Removes a listener from this {@code CheckBoxList} so that if it had been added earlier, it will no longer be
177 * called on user actions
178 * @param listener Listener to remove from this {@code CheckBoxList}
179 * @return Itself
180 */
181 public CheckBoxList<V> removeListener(Listener listener) {
182 listeners.remove(listener);
183 return this;
184 }
185
186 @Override
187 public synchronized Result handleKeyStroke(KeyStroke keyStroke) {
188 if(keyStroke.getKeyType() == KeyType.Enter ||
189 (keyStroke.getKeyType() == KeyType.Character && keyStroke.getCharacter() == ' ')) {
190 if(itemStatus.get(getSelectedIndex()))
191 setChecked(getSelectedIndex(), Boolean.FALSE);
192 else
193 setChecked(getSelectedIndex(), Boolean.TRUE);
194 return Result.HANDLED;
195 }
196 return super.handleKeyStroke(keyStroke);
197 }
198
199 /**
200 * Default renderer for this component which is used unless overridden. The checked state is drawn on the left side
201 * of the item label using a "[ ]" block filled with an X if the item has checked state on
202 * @param <V>
203 */
204 public static class CheckBoxListItemRenderer<V> extends ListItemRenderer<V,CheckBoxList<V>> {
205 @Override
206 public int getHotSpotPositionOnLine(int selectedIndex) {
207 return 1;
208 }
209
210 @Override
211 public String getLabel(CheckBoxList<V> listBox, int index, V item) {
212 String check = " ";
213 List<Boolean> itemStatus = listBox.itemStatus;
214 if(itemStatus.get(index))
215 check = "x";
216
217 String text = item.toString();
218 return "[" + check + "] " + text;
219 }
220 }
221 }