1 /*
2 Copyright 2007-2014 Fraunhofer IGD, http://www.igd.fraunhofer.de
3 Fraunhofer-Gesellschaft - Institute for Computer Graphics Research
4
5 See the NOTICE file distributed with this work for additional
6 information regarding copyright ownership
7
8 Licensed under the Apache License, Version 2.0 (the "License");
9 you may not use this file except in compliance with the License.
10 You may obtain a copy of the License at
11
12 http://www.apache.org/licenses/LICENSE-2.0
13
14 Unless required by applicable law or agreed to in writing, software
15 distributed under the License is distributed on an "AS IS" BASIS,
16 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
17 See the License for the specific language governing permissions and
18 limitations under the License.
19 */
20 package org.universAAL.middleware.ui.rdf;
21
22 import java.util.ArrayList;
23 import java.util.Iterator;
24 import java.util.List;
25
26 import org.universAAL.middleware.container.utils.StringUtils;
27 import org.universAAL.middleware.owl.MergedRestriction;
28 import org.universAAL.middleware.rdf.PropertyPath;
29 import org.universAAL.middleware.rdf.Resource;
30
31 /**
32 * An input control to be used if the user input is restricted to a fixed list
33 * of acceptable values. As it allows multiple selections, it can be seen as an
34 * abbreviation for a {@link Repeat} control having only a {@link Select1} as
35 * child.
36 *
37 * @author mtazari
38 * @author Carsten Stockloew
39 * @navassoc "" - "*" Label
40 */
41 public class Select extends Input {
42 public static final String MY_URI = Form.uAAL_DIALOG_NAMESPACE + "Select";
43
44 /**
45 * The list of choices in a select control. List members must be instances
46 * of either {@link ChoiceItem} or {@link ChoiceList}.
47 */
48 public static final String PROP_CHOICES = Form.uAAL_DIALOG_NAMESPACE
49 + "choices";
50
51 /**
52 * Just for use by de-serializers.
53 */
54 public Select() {
55 super();
56 }
57
58 /**
59 * For use by applications.
60 *
61 * @param parent
62 * The group to contain this select object.
63 * @param label
64 * The label.
65 * @param ref
66 * mandatory property path within the form data to which this
67 * select object refers.
68 * @param valueRestriction
69 * Optional local restrictions on the value of this select
70 * object.
71 * @param initialValue
72 * Optional initial / default value that will be made available
73 * in the form data.
74 */
75 public Select(Group parent, Label label, PropertyPath ref,
76 MergedRestriction valueRestriction, Object initialValue) {
77 super(MY_URI, parent, label, ref, valueRestriction, initialValue);
78 }
79
80 protected Select(String typeURI, Group parent, Label label,
81 PropertyPath ref, MergedRestriction valueRestriction,
82 Object initialValue) {
83 super(typeURI, parent, label, ref, valueRestriction, initialValue);
84 }
85
86 /**
87 * Adds the given choice item to the list of choices in this select control.
88 */
89 public void addChoiceItem(ChoiceItem item) {
90 if (item != null) {
91 List l = (List) props.get(PROP_CHOICES);
92 if (l == null) {
93 l = new ArrayList();
94 props.put(PROP_CHOICES, l);
95 }
96 l.add(item);
97 }
98 }
99
100 /**
101 * Adds the given choice list as a sublist to the list of choices in this
102 * select control.
103 */
104 public void addChoiceList(ChoiceList list) {
105 if (list != null) {
106 List l = (List) props.get(PROP_CHOICES);
107 if (l == null) {
108 l = new ArrayList();
109 props.put(PROP_CHOICES, l);
110 }
111 l.add(list);
112 }
113 }
114
115 /**
116 * Having the actual values that the user should select from among them,
117 * this method automatically generates the list of choices for this select
118 * by trying to derive a label for them. No sublists can be generated by
119 * this method.
120 *
121 * @return true if the given parameter is a non empty array without any null
122 * element, false otherwise.
123 */
124 public boolean generateChoices(Object[] elems) {
125 if (elems == null || elems.length == 0)
126 return false;
127
128 for (int i = 0; i < elems.length; i++) {
129 if (elems[i] == null)
130 return false;
131 String label = (elems[i] instanceof Resource) ? ((Resource) elems[i])
132 .getResourceLabel()
133 : null;
134 if (label == null)
135 label = elems[i].toString();
136 addChoiceItem(new ChoiceItem(StringUtils.deriveLabel(label), null,
137 elems[i]));
138 }
139
140 return true;
141 }
142
143 /**
144 * If the restrictions defined or derivable for this select control can be
145 * determined and a certain list of allowed values can be derived from those
146 * restriction, those values will be passed to
147 * {@link #generateChoices(Object[])} to construct the list of choices.
148 */
149 public boolean generateChoices() {
150 MergedRestriction r = getRestrictions();
151 return (r == null) ? false : generateChoices(r.getEnumeratedValues());
152 }
153
154 /**
155 * Returns the list of choices in this select control. Each of the elements
156 * in the returned array is supposed to be an instance of either
157 * {@link ChoiceItem} or {@link ChoiceList}.
158 */
159 public Label[] getChoices() {
160 List l = (List) props.get(PROP_CHOICES);
161 if (l == null)
162 return new Label[0];
163
164 return (Label[]) l.toArray(new Label[l.size()]);
165 }
166
167 /**
168 * Returns the maximum number of values that can be selected in the context
169 * of this select control. A negative integer is returned if there is no
170 * upper limit.
171 */
172 public int getMaxCardinality() {
173 MergedRestriction r = getRestrictions();
174 return (r == null) ? -1 : r.getMaxCardinality();
175 }
176
177 /**
178 * Overrides {@link FormControl#getMaxLength()} by only considering the
179 * labels of the choices currently associated with this select control.
180 */
181 public int getMaxLength() {
182 List l = (List) props.get(PROP_CHOICES);
183 if (l == null)
184 return -1;
185
186 int res = -1;
187 for (Iterator i = l.iterator(); i.hasNext();) {
188 Object o = i.next();
189 if (o instanceof Label) {
190 int aux = ((Label) o).getMaxLength();
191 if (aux > res)
192 res = aux;
193 }
194 }
195 return res;
196 }
197
198 /**
199 * Returns the minimum number of values that must be associated with this
200 * select control as selected values. A non-positive integer is returned if
201 * there is no lower limit.
202 */
203 public int getMinCardinality() {
204 MergedRestriction r = getRestrictions();
205 return (r == null) ? -1 : r.getMinCardinality();
206 }
207
208 /**
209 * Checks if any sublist is contained in the list of choices in this select
210 * control.
211 */
212 public boolean isMultilevel() {
213 List l = (List) props.get(PROP_CHOICES);
214 if (l == null)
215 return false;
216
217 for (Iterator i = l.iterator(); i.hasNext();)
218 if (i.next() instanceof ChoiceList)
219 return true;
220
221 return false;
222 }
223
224 /**
225 * Just for use by de-serializers.
226 *
227 * @see org.universAAL.middleware.rdf.Resource#setProperty(String, Object)
228 */
229 public boolean setProperty(String propURI, Object value) {
230 if (PROP_CHOICES.equals(propURI)) {
231 if (props.containsKey(propURI))
232 return false;
233 else if (value instanceof List) {
234 for (Iterator i = ((List) value).iterator(); i.hasNext();) {
235 Object o = i.next();
236 if (!(o instanceof ChoiceItem)
237 && !(o instanceof ChoiceList))
238 return false;
239 }
240 props.put(propURI, value);
241 return true;
242 } else if (value instanceof ChoiceItem
243 || value instanceof ChoiceList) {
244 List l = new ArrayList(1);
245 l.add(value);
246 props.put(propURI, l);
247 return true;
248 }
249 } else
250 return super.setProperty(propURI, value);
251 return false;
252 }
253
254 /**
255 * Tries to find the hidden value associated with a choice item whose label
256 * has been given as input and then store that value as user input by
257 * calling {@link #storeUserInput(Object)}. If no hidden value was found,
258 * the label itself will be used as user input.
259 *
260 * Note: for use by UI handlers that can not handle the association between
261 * labels and values internally.
262 *
263 * @return true, if the storage was successful, false otherwise.
264 */
265 public boolean storeUserInputByLabelString(String selectedLabelString) {
266 if (selectedLabelString != null) {
267 List l = (List) props.get(PROP_CHOICES);
268 if (l != null)
269 for (Iterator i = l.iterator(); i.hasNext();) {
270 Object label = i.next();
271 if (label instanceof ChoiceList)
272 label = ((ChoiceList) label)
273 .findItem(selectedLabelString);
274 if (label instanceof ChoiceItem
275 && selectedLabelString.equals(label.toString()))
276 return storeUserInput(((ChoiceItem) label).getValue());
277 }
278 }
279 return storeUserInput(selectedLabelString);
280 }
281 }