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39
40
41#include "qtextlist.h"
42#include "qtextobject_p.h"
43#include "qtextcursor.h"
44#include "qtextdocument_p.h"
45#include <qdebug.h>
46
47QT_BEGIN_NAMESPACE
48
49class QTextListPrivate : public QTextBlockGroupPrivate
50{
51public:
52 QTextListPrivate(QTextDocument *doc)
53 : QTextBlockGroupPrivate(doc)
54 {
55 }
56};
57
58/*!
59 \class QTextList
60 \reentrant
61
62 \brief The QTextList class provides a decorated list of items in a QTextDocument.
63 \inmodule QtGui
64
65 \ingroup richtext-processing
66
67 A list contains a sequence of text blocks, each of which is marked with a
68 bullet point or other symbol. Multiple levels of lists can be used, and
69 the automatic numbering feature provides support for ordered numeric and
70 alphabetical lists.
71
72 Lists are created by using a text cursor to insert an empty list at the
73 current position or by moving existing text into a new list.
74 The \l{QTextCursor::insertList()} function inserts an empty block into the
75 document at the cursor position, and makes it the first item in a list.
76
77 \snippet textdocument-lists/mainwindow.cpp 0
78
79 The \l{QTextCursor::createList()} function takes the contents of the
80 cursor's current block and turns it into the first item of a new list.
81
82 The cursor's current list is found with \l{QTextCursor::currentList()}.
83
84 The number of items in a list is given by count(). Each item can be
85 obtained by its index in the list with the item() function. Similarly,
86 the index of a given item can be found with itemNumber(). The text of
87 each item can be found with the itemText() function.
88
89 Note that the items in the list may not be adjacent elements in the
90 document. For example, the top-level items in a multi-level list will
91 be separated by the items in lower levels of the list.
92
93 List items can be deleted by index with the removeItem() function.
94 remove() deletes the specified item in the list.
95
96 The list's format is set with setFormat() and read with format().
97 The format describes the decoration of the list itself, and not the
98 individual items.
99
100 \sa QTextBlock, QTextListFormat, QTextCursor
101*/
102
103#if QT_DEPRECATED_SINCE(5, 13)
104/*!
105 \fn bool QTextList::isEmpty() const
106 \obsolete
107
108 Returns \c true if the list has no items; otherwise returns \c false.
109
110 \b{Note:} Empty lists are automatically deleted by the QTextDocument that owns
111 them.
112
113 \sa count()
114*/
115#endif
116
117/*! \internal
118 */
119QTextList::QTextList(QTextDocument *doc)
120 : QTextBlockGroup(*new QTextListPrivate(doc), doc)
121{
122}
123
124/*!
125 \internal
126*/
127QTextList::~QTextList()
128{
129}
130
131/*!
132 Returns the number of items in the list.
133*/
134int QTextList::count() const
135{
136 Q_D(const QTextList);
137 return d->blocks.count();
138}
139
140/*!
141 Returns the \a{i}-th text block in the list.
142
143 \sa count(), itemText()
144*/
145QTextBlock QTextList::item(int i) const
146{
147 Q_D(const QTextList);
148 if (i < 0 || i >= d->blocks.size())
149 return QTextBlock();
150 return d->blocks.at(i);
151}
152
153/*!
154 \fn void QTextList::setFormat(const QTextListFormat &format)
155
156 Sets the list's format to \a format.
157*/
158
159/*!
160 \fn QTextListFormat QTextList::format() const
161
162 Returns the list's format.
163*/
164
165/*!
166 \fn int QTextList::itemNumber(const QTextBlock &block) const
167
168 Returns the index of the list item that corresponds to the given \a block.
169 Returns -1 if the block was not present in the list.
170*/
171int QTextList::itemNumber(const QTextBlock &blockIt) const
172{
173 Q_D(const QTextList);
174 return d->blocks.indexOf(t: blockIt);
175}
176
177/*!
178 \fn QString QTextList::itemText(const QTextBlock &block) const
179
180 Returns the text of the list item that corresponds to the given \a block.
181*/
182QString QTextList::itemText(const QTextBlock &blockIt) const
183{
184 Q_D(const QTextList);
185 int item = d->blocks.indexOf(t: blockIt) + 1;
186 if (item <= 0)
187 return QString();
188
189 QTextBlock block = d->blocks.at(i: item-1);
190 QTextBlockFormat blockFormat = block.blockFormat();
191
192 QString result;
193
194 const int style = format().style();
195 QString numberPrefix;
196 QString numberSuffix = QLatin1String(".");
197
198 if (format().hasProperty(propertyId: QTextFormat::ListNumberPrefix))
199 numberPrefix = format().numberPrefix();
200 if (format().hasProperty(propertyId: QTextFormat::ListNumberSuffix))
201 numberSuffix = format().numberSuffix();
202
203 switch (style) {
204 case QTextListFormat::ListDecimal:
205 result = QString::number(item);
206 break;
207 // from the old richtext
208 case QTextListFormat::ListLowerAlpha:
209 case QTextListFormat::ListUpperAlpha:
210 {
211 const char baseChar = style == QTextListFormat::ListUpperAlpha ? 'A' : 'a';
212
213 int c = item;
214 while (c > 0) {
215 c--;
216 result.prepend(c: QChar(baseChar + (c % 26)));
217 c /= 26;
218 }
219 }
220 break;
221 case QTextListFormat::ListLowerRoman:
222 case QTextListFormat::ListUpperRoman:
223 {
224 if (item < 5000) {
225 QByteArray romanNumeral;
226
227 // works for up to 4999 items
228 static const char romanSymbolsLower[] = "iiivixxxlxcccdcmmmm";
229 static const char romanSymbolsUpper[] = "IIIVIXXXLXCCCDCMMMM";
230 QByteArray romanSymbols; // wrap to have "mid"
231 if (style == QTextListFormat::ListLowerRoman)
232 romanSymbols = QByteArray::fromRawData(romanSymbolsLower, size: sizeof(romanSymbolsLower));
233 else
234 romanSymbols = QByteArray::fromRawData(romanSymbolsUpper, size: sizeof(romanSymbolsUpper));
235
236 int c[] = { 1, 4, 5, 9, 10, 40, 50, 90, 100, 400, 500, 900, 1000 };
237 int n = item;
238 for (int i = 12; i >= 0; n %= c[i], i--) {
239 int q = n / c[i];
240 if (q > 0) {
241 int startDigit = i + (i+3)/4;
242 int numDigits;
243 if (i % 4) {
244 // c[i] == 4|5|9|40|50|90|400|500|900
245 if ((i-2) % 4) {
246 // c[i] == 4|9|40|90|400|900 => with subtraction (IV, IX, XL, XC, ...)
247 numDigits = 2;
248 }
249 else {
250 // c[i] == 5|50|500 (V, L, D)
251 numDigits = 1;
252 }
253 }
254 else {
255 // c[i] == 1|10|100|1000 (I, II, III, X, XX, ...)
256 numDigits = q;
257 }
258
259 romanNumeral.append(a: romanSymbols.mid(index: startDigit, len: numDigits));
260 }
261 }
262 result = QString::fromLatin1(str: romanNumeral);
263 }
264 else {
265 result = QLatin1String("?");
266 }
267
268 }
269 break;
270 default:
271 Q_ASSERT(false);
272 }
273 if (blockIt.textDirection() == Qt::RightToLeft)
274 return numberSuffix + result + numberPrefix;
275 else
276 return numberPrefix + result + numberSuffix;
277}
278
279/*!
280 Removes the item at item position \a i from the list. When the last item in the
281 list is removed, the list is automatically deleted by the QTextDocument that owns
282 it.
283
284 \sa add(), remove()
285*/
286void QTextList::removeItem(int i)
287{
288 Q_D(QTextList);
289 if (i < 0 || i >= d->blocks.size())
290 return;
291
292 QTextBlock block = d->blocks.at(i);
293 remove(block);
294}
295
296
297/*!
298 Removes the given \a block from the list.
299
300 \sa add(), removeItem()
301*/
302void QTextList::remove(const QTextBlock &block)
303{
304 QTextBlockFormat fmt = block.blockFormat();
305 fmt.setIndent(fmt.indent() + format().indent());
306 fmt.setObjectIndex(-1);
307 block.docHandle()->setBlockFormat(from: block, to: block, newFormat: fmt, mode: QTextDocumentPrivate::SetFormat);
308}
309
310/*!
311 Makes the given \a block part of the list.
312
313 \sa remove(), removeItem()
314*/
315void QTextList::add(const QTextBlock &block)
316{
317 QTextBlockFormat fmt = block.blockFormat();
318 fmt.setObjectIndex(objectIndex());
319 block.docHandle()->setBlockFormat(from: block, to: block, newFormat: fmt, mode: QTextDocumentPrivate::SetFormat);
320}
321
322QT_END_NAMESPACE
323

source code of qtbase/src/gui/text/qtextlist.cpp