src/kitemviews/kitemrange.h

   1 /***************************************************************************
   2  *   Copyright (C) 2011 by Peter Penz <peter.penz19@gmail.com>             *
   3  *   Copyright (C) 2013 by Frank Reininghaus <frank78ac@googlemail.com>    *
   4  *                                                                         *
   5  *   Based on the Itemviews NG project from Trolltech Labs                 *
   6  *                                                                         *
   7  *   This program is free software; you can redistribute it and/or modify  *
   8  *   it under the terms of the GNU General Public License as published by  *
   9  *   the Free Software Foundation; either version 2 of the License, or     *
  10  *   (at your option) any later version.                                   *
  11  *                                                                         *
  12  *   This program is distributed in the hope that it will be useful,       *
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  15  *   GNU General Public License for more details.                          *
  16  *                                                                         *
  17  *   You should have received a copy of the GNU General Public License     *
  18  *   along with this program; if not, write to the                         *
  19  *   Free Software Foundation, Inc.,                                       *
  20  *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA            *
  21  ***************************************************************************/
  22
  23 #ifndef KITEMRANGE_H
  24 #define KITEMRANGE_H
  25
  26 #include <QList>
  27
  28 struct KItemRange
  29 {
  30     KItemRange(int index = 0, int count = 0);
  31     int index;
  32     int count;
  33
  34     bool operator == (const KItemRange& other) const;
  35 };
  36
  37 inline KItemRange::KItemRange(int index, int count) :
  38     index(index),
  39     count(count)
  40 {
  41 }
  42
  43 inline bool KItemRange::operator == (const KItemRange& other) const
  44 {
  45     return index == other.index && count == other.count;
  46 }
  47
  48
  49 class KItemRangeList : public QList<KItemRange>
  50 {
  51 public:
  52     KItemRangeList() : QList<KItemRange>() {}
  53     explicit KItemRangeList(const QList<KItemRange>& list) : QList<KItemRange>(list) {}
  54
  55     template<class Container>
  56     static KItemRangeList fromSortedContainer(const Container& container);
  57
  58     KItemRangeList& operator<<(const KItemRange& range)
  59     {
  60         append(range);
  61         return *this;
  62     }
  63 };
  64
  65 template<class Container>
  66 KItemRangeList KItemRangeList::fromSortedContainer(const Container& container)
  67 {
  68     typename Container::const_iterator it = container.constBegin();
  69     const typename Container::const_iterator end = container.constEnd();
  70
  71     if (it == end) {
  72         return KItemRangeList();
  73     }
  74
  75     KItemRangeList result;
  76
  77     int index = *it;
  78     int count = 1;
  79
  80     // Remove duplicates, see https://bugs.kde.org/show_bug.cgi?id=335672
  81     while (it != end && *it == index) {
  82         ++it;
  83     }
  84
  85     while (it != end) {
  86         if (*it == index + count) {
  87             ++count;
  88         } else {
  89             result << KItemRange(index, count);
  90             index = *it;
  91             count = 1;
  92         }
  93         ++it;
  94
  95         // Remove duplicates, see https://bugs.kde.org/show_bug.cgi?id=335672
  96         while (it != end && *it == *(it - 1)) {
  97             ++it;
  98         }
  99     }
 100
 101     result << KItemRange(index, count);
 102     return result;
 103 }
 104
 105 #endif