src/kitemviews/kitemlistviewlayouter_p.h

   1 /***************************************************************************
   2  *   Copyright (C) 2011 by Peter Penz <peter.penz19@gmail.com>             *
   3  *                                                                         *
   4  *   This program is free software; you can redistribute it and/or modify  *
   5  *   it under the terms of the GNU General Public License as published by  *
   6  *   the Free Software Foundation; either version 2 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 General Public License for more details.                          *
  13  *                                                                         *
  14  *   You should have received a copy of the GNU General Public License     *
  15  *   along with this program; if not, write to the                         *
  16  *   Free Software Foundation, Inc.,                                       *
  17  *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA            *
  18  ***************************************************************************/
  19
  20 #ifndef KITEMLISTVIEWLAYOUTER_H
  21 #define KITEMLISTVIEWLAYOUTER_H
  22
  23 #include <libdolphin_export.h>
  24
  25 #include <QObject>
  26 #include <QRectF>
  27 #include <QSet>
  28 #include <QSizeF>
  29
  30 class KItemModelBase;
  31 class KItemListSizeHintResolver;
  32
  33 class LIBDOLPHINPRIVATE_EXPORT KItemListViewLayouter : public QObject
  34 {
  35     Q_OBJECT
  36
  37 public:
  38     KItemListViewLayouter(QObject* parent = 0);
  39     virtual ~KItemListViewLayouter();
  40
  41     void setScrollOrientation(Qt::Orientation orientation);
  42     Qt::Orientation scrollOrientation() const;
  43
  44     void setSize(const QSizeF& size);
  45     QSizeF size() const;
  46
  47     void setItemSize(const QSizeF& size);
  48     QSizeF itemSize() const;
  49
  50     /**
  51      * Sets the height of the header that is always aligned
  52      * at the top. A height of <= 0.0 means that no header is
  53      * used.
  54      */
  55     void setHeaderHeight(qreal height);
  56     qreal headerHeight() const;
  57
  58     /**
  59      * Sets the height of the group header that is used
  60      * to indicate a new item group.
  61      */
  62     void setGroupHeaderHeight(qreal height);
  63     qreal groupHeaderHeight() const;
  64
  65     // TODO: add note that offset can be < 0 or > maximumOffset!
  66     void setScrollOffset(qreal scrollOffset);
  67     qreal scrollOffset() const;
  68
  69     qreal maximumScrollOffset() const;
  70
  71     void setItemOffset(qreal scrollOffset);
  72     qreal itemOffset() const;
  73
  74     qreal maximumItemOffset() const;
  75
  76     void setModel(const KItemModelBase* model);
  77     const KItemModelBase* model() const;
  78
  79     void setSizeHintResolver(const KItemListSizeHintResolver* sizeHintResolver);
  80     const KItemListSizeHintResolver* sizeHintResolver() const;
  81
  82     /**
  83      * @return The first (at least partly) visible index. -1 is returned
  84      *         if the item count is 0.
  85      */
  86     int firstVisibleIndex() const;
  87
  88     /**
  89      * @return The last (at least partly) visible index. -1 is returned
  90      *         if the item count is 0.
  91      */
  92     int lastVisibleIndex() const;
  93
  94     /**
  95      * @return Rectangle of the item with the index \a index.
  96      *         The top/left of the bounding rectangle is related to
  97      *         the top/left of the KItemListView. An empty rectangle
  98      *         is returned if an invalid index is given.
  99      */
 100     QRectF itemRect(int index) const;
 101
 102     QRectF groupHeaderRect(int index) const;
 103
 104     /**
 105      * @return Maximum number of (at least partly) visible items for
 106      *         the given size.
 107      */
 108     int maximumVisibleItems() const;
 109
 110     /**
 111      * @return Maximum number of items that can be shown in the same row
 112      *          (= vertical scrolldirection) or same column
 113      *          (= horizontal scrolldirection).
 114      */
 115     int itemsPerOffset() const;
 116
 117     /**
 118      * @return True if the item with the index \p itemIndex
 119      *         is the first item within a group.
 120      */
 121     bool isFirstGroupItem(int itemIndex) const;
 122
 123     void markAsDirty();
 124
 125 private:
 126     void doLayout();
 127     void updateVisibleIndexes();
 128     bool createGroupHeaders();
 129
 130 private:
 131     bool m_dirty;
 132     bool m_visibleIndexesDirty;
 133
 134     Qt::Orientation m_scrollOrientation;
 135     QSizeF m_size;
 136
 137     QSizeF m_itemSize;
 138     qreal m_headerHeight;
 139     const KItemModelBase* m_model;
 140     const KItemListSizeHintResolver* m_sizeHintResolver;
 141
 142     qreal m_scrollOffset;
 143     qreal m_maximumScrollOffset;
 144
 145     qreal m_itemOffset;
 146     qreal m_maximumItemOffset;
 147
 148     int m_firstVisibleIndex;
 149     int m_lastVisibleIndex;
 150
 151     qreal m_columnWidth;
 152     qreal m_xPosInc;
 153     int m_columnCount;
 154
 155     // Stores all item indexes that are the first item of a group.
 156     // Assures fast access for KItemListViewLayouter::isFirstGroupItem().
 157     QSet<int> m_groupItemIndexes;
 158     qreal m_groupHeaderHeight;
 159
 160     QList<QRectF> m_itemRects;
 161 };
 162
 163 #endif
 164
 165