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  #ifndef QLISTVIEW_P_H
  #define QLISTVIEW_P_H
  
  //
  //  W A R N I N G
  //  -------------
  //
  // This file is not part of the Qt API.  It exists for the convenience
  // of other Qt classes.  This header file may change from version to
  // version without notice, or even be removed.
  //
  // We mean it.
  //
  
  #include "private/qabstractitemview_p.h"
  #include "qrubberband.h"
  #include "qbitarray.h"
  #include "qbsptree_p.h"
  #include <limits.h>
  #include <qscrollbar.h>
  
  #ifndef QT_NO_LISTVIEW
  
  QT_BEGIN_NAMESPACE
  
  class QListViewItem
  {
      friend class QListViewPrivate;
      friend class QListModeViewBase;
      friend class QIconModeViewBase;
  public:
      inline QListViewItem()
          : x(-1), y(-1), w(0), h(0), indexHint(-1), visited(0xffff) {}
      inline QListViewItem(const QListViewItem &other)
          : x(other.x), y(other.y), w(other.w), h(other.h),
            indexHint(other.indexHint), visited(other.visited) {}
      inline QListViewItem(QRect r, int i)
          : x(r.x()), y(r.y()), w(qMin(r.width(), SHRT_MAX)), h(qMin(r.height(), SHRT_MAX)),
            indexHint(i), visited(0xffff) {}
      inline bool operator==(const QListViewItem &other) const {
          return (x == other.x && y == other.y && w == other.w && h == other.h &&
                  indexHint == other.indexHint); }
      inline bool operator!=(const QListViewItem &other) const
          { return !(*this == other); }
      inline bool isValid() const
          { return rect().isValid() && (indexHint > -1); }
      inline void invalidate()
          { x = -1; y = -1; w = 0; h = 0; }
      inline void resize(const QSize &size)
          { w = qMin(size.width(), SHRT_MAX); h = qMin(size.height(), SHRT_MAX); }
      inline void move(const QPoint &position)
          { x = position.x(); y = position.y(); }
      inline int width() const { return w; }
      inline int height() const { return h; }
  private:
      inline QRect rect() const
          { return QRect(x, y, w, h); }
      int x, y;
      short w, h;
      mutable int indexHint;
      uint visited;
  };
  
  struct QListViewLayoutInfo
  {
      QRect bounds;
      QSize grid;
      int spacing;
      int first;
      int last;
      bool wrap;
      QListView::Flow flow;
      int max;
  };
  
  class QListView;
  class QListViewPrivate;
  
  class QCommonListViewBase
  {
  public:
      inline QCommonListViewBase(QListView *q, QListViewPrivate *d) : dd(d), qq(q), batchStartRow(0), batchSavedDeltaSeg(0) {}
      virtual ~QCommonListViewBase() {}
  
      //common interface
      virtual int itemIndex(const QListViewItem &item) const = 0;
      virtual QListViewItem indexToListViewItem(const QModelIndex &index) const = 0;
      virtual bool doBatchedItemLayout(const QListViewLayoutInfo &info, int max) = 0;
      virtual void clear() = 0;
      virtual void setRowCount(int) = 0;
      virtual QVector<QModelIndex> intersectingSet(const QRect &area) const = 0;
      virtual void dataChanged(const QModelIndex &, const QModelIndex &) = 0;
  
      virtual int horizontalScrollToValue(int index, QListView::ScrollHint hint,
          bool leftOf, bool rightOf, const QRect &area, const QRect &rect) const;
      virtual int verticalScrollToValue(int index, QListView::ScrollHint hint,
          bool above, bool below, const QRect &area, const QRect &rect) const;
      virtual void scrollContentsBy(int dx, int dy, bool scrollElasticBand);
      virtual QRect mapToViewport(const QRect &rect) const {return rect;}
      virtual int horizontalOffset() const;
      virtual int verticalOffset() const { return verticalScrollBar()->value(); }
      virtual void updateHorizontalScrollBar(const QSize &step);
      virtual void updateVerticalScrollBar(const QSize &step);
      virtual void appendHiddenRow(int row);
      virtual void removeHiddenRow(int row);
      virtual void setPositionForIndex(const QPoint &, const QModelIndex &) { }
  
  #ifndef QT_NO_DRAGANDDROP
      virtual void paintDragDrop(QPainter *painter) = 0;
      virtual bool filterDragMoveEvent(QDragMoveEvent *) { return false; }
      virtual bool filterDragLeaveEvent(QDragLeaveEvent *) { return false; }
      virtual bool filterDropEvent(QDropEvent *) { return false; }
      virtual bool filterStartDrag(Qt::DropActions) { return false; }
  #endif
  
  
      //other inline members
      inline int spacing() const;
      inline bool isWrapping() const;
      inline QSize gridSize() const;
      inline QListView::Flow flow() const;
      inline QListView::Movement movement() const;
  
      inline QPoint offset() const;
      inline QPoint pressedPosition() const;
      inline bool uniformItemSizes() const;
      inline int column() const;
  
      inline QScrollBar *verticalScrollBar() const;
      inline QScrollBar *horizontalScrollBar() const;
      inline QListView::ScrollMode verticalScrollMode() const;
      inline QListView::ScrollMode horizontalScrollMode() const;
  
      inline QModelIndex modelIndex(int row) const;
      inline int rowCount() const;
  
      inline QStyleOptionViewItem viewOptions() const;
      inline QWidget *viewport() const;
      inline QRect clipRect() const;
  
      inline QSize cachedItemSize() const;
      inline QRect viewItemRect(const QListViewItem &item) const;
      inline QSize itemSize(const QStyleOptionViewItem &opt, const QModelIndex &idx) const;
      inline QAbstractItemDelegate *delegate(const QModelIndex &idx) const;
  
      inline bool isHidden(int row) const;
      inline int hiddenCount() const;
  
      inline bool isRightToLeft() const;
  
      QListViewPrivate *dd;
      QListView *qq;
      QSize contentsSize;
      int batchStartRow;
      int batchSavedDeltaSeg;
  };
  
  class QListModeViewBase : public QCommonListViewBase
  {
  public:
      QListModeViewBase(QListView *q, QListViewPrivate *d) : QCommonListViewBase(q, d) {}
  
      QVector<int> flowPositions;
      QVector<int> segmentPositions;
      QVector<int> segmentStartRows;
      QVector<int> segmentExtents;
      QVector<int> scrollValueMap;
  
      // used when laying out in batches
      int batchSavedPosition;
  
      //reimplementations
      int itemIndex(const QListViewItem &item) const { return item.indexHint; }
      QListViewItem indexToListViewItem(const QModelIndex &index) const;
      bool doBatchedItemLayout(const QListViewLayoutInfo &info, int max);
      void clear();
      void setRowCount(int rowCount) { flowPositions.resize(rowCount); }
      QVector<QModelIndex> intersectingSet(const QRect &area) const;
      void dataChanged(const QModelIndex &, const QModelIndex &);
  
      int horizontalScrollToValue(int index, QListView::ScrollHint hint,
          bool leftOf, bool rightOf,const QRect &area, const QRect &rect) const;
      int verticalScrollToValue(int index, QListView::ScrollHint hint,
          bool above, bool below, const QRect &area, const QRect &rect) const;
      void scrollContentsBy(int dx, int dy, bool scrollElasticBand);
      QRect mapToViewport(const QRect &rect) const;
      int horizontalOffset() const;
      int verticalOffset() const;
      void updateHorizontalScrollBar(const QSize &step);
      void updateVerticalScrollBar(const QSize &step);
  
  #ifndef QT_NO_DRAGANDDROP
      void paintDragDrop(QPainter *painter);
  
      // The next two methods are to be used on LefToRight flow only.
      // WARNING: Plenty of duplicated code from QAbstractItemView{,Private}.
      QAbstractItemView::DropIndicatorPosition position(const QPoint &pos, const QRect &rect, const QModelIndex &idx) const;
      void dragMoveEvent(QDragMoveEvent *e);
      bool dropOn(QDropEvent *event, int *row, int *col, QModelIndex *index);
  #endif
  
  private:
      QPoint initStaticLayout(const QListViewLayoutInfo &info);
      void doStaticLayout(const QListViewLayoutInfo &info);
      int perItemScrollToValue(int index, int value, int height,
                               QAbstractItemView::ScrollHint hint,
                               Qt::Orientation orientation, bool wrap, int extent) const;
      int perItemScrollingPageSteps(int length, int bounds, bool wrap) const;
  };
  
  class QIconModeViewBase : public QCommonListViewBase
  {
  public:
      QIconModeViewBase(QListView *q, QListViewPrivate *d) : QCommonListViewBase(q, d), interSectingVector(0) {}
  
      QBspTree tree;
      QVector<QListViewItem> items;
      QBitArray moved;
  
      QVector<QModelIndex> draggedItems; // indices to the tree.itemVector
      mutable QPoint draggedItemsPos;
  
      // used when laying out in batches
      QVector<QModelIndex> *interSectingVector; //used from within intersectingSet
  
      //reimplementations
      int itemIndex(const QListViewItem &item) const;
      QListViewItem indexToListViewItem(const QModelIndex &index) const;
      bool doBatchedItemLayout(const QListViewLayoutInfo &info, int max);
      void clear();
      void setRowCount(int rowCount);
      QVector<QModelIndex> intersectingSet(const QRect &area) const;
  
      void scrollContentsBy(int dx, int dy, bool scrollElasticBand);
      void dataChanged(const QModelIndex &topLeft, const QModelIndex &bottomRight);
      void appendHiddenRow(int row);
      void removeHiddenRow(int row);
      void setPositionForIndex(const QPoint &position, const QModelIndex &index);
  
  #ifndef QT_NO_DRAGANDDROP
      void paintDragDrop(QPainter *painter);
      bool filterDragMoveEvent(QDragMoveEvent *);
      bool filterDragLeaveEvent(QDragLeaveEvent *);
      bool filterDropEvent(QDropEvent *e);
      bool filterStartDrag(Qt::DropActions);
  #endif
  
  private:
      void initBspTree(const QSize &contents);
      QPoint initDynamicLayout(const QListViewLayoutInfo &info);
      void doDynamicLayout(const QListViewLayoutInfo &info);
      static void addLeaf(QVector<int> &leaf, const QRect &area,
                          uint visited, QBspTree::Data data);
      QRect itemsRect(const QVector<QModelIndex> &indexes) const;
      QRect draggedItemsRect() const;
      QPoint snapToGrid(const QPoint &pos) const;
      void updateContentsSize();
      QPoint draggedItemsDelta() const;
      void drawItems(QPainter *painter, const QVector<QModelIndex> &indexes) const;
      void moveItem(int index, const QPoint &dest);
  
  };
  
  class QListViewPrivate: public QAbstractItemViewPrivate
  {
      Q_DECLARE_PUBLIC(QListView)
  public:
      QListViewPrivate();
      ~QListViewPrivate();
  
      void clear();
      void prepareItemsLayout();
  
      bool doItemsLayout(int num);
  
      inline QVector<QModelIndex> intersectingSet(const QRect &area, bool doLayout = true) const {
          if (doLayout) executePostedLayout();
          QRect a = (q_func()->isRightToLeft() ? flipX(area.normalized()) : area.normalized());
          return commonListView->intersectingSet(a);
      }
  
      inline void resetBatchStartRow() { commonListView->batchStartRow = 0; }
      inline int batchStartRow() const { return commonListView->batchStartRow; }
      inline QSize contentsSize() const { return commonListView->contentsSize; }
      inline void setContentsSize(int w, int h) { commonListView->contentsSize = QSize(w, h); }
  
      inline int flipX(int x) const
          { return qMax(viewport->width(), contentsSize().width()) - x; }
      inline QPoint flipX(const QPoint &p) const
          { return QPoint(flipX(p.x()), p.y()); }
      inline QRect flipX(const QRect &r) const
          { return QRect(flipX(r.x()) - r.width(), r.y(), r.width(), r.height()); }
      inline QRect viewItemRect(const QListViewItem &item) const
          { if (q_func()->isRightToLeft()) return flipX(item.rect()); return item.rect(); }
  
      QListViewItem indexToListViewItem(const QModelIndex &index) const;
      inline QModelIndex listViewItemToIndex(const QListViewItem &item) const
          { return model->index(commonListView->itemIndex(item), column, root); }
  
      QRect rectForIndex(const QModelIndex &index) const
      {
          if (!isIndexValid(index) || index.parent() != root || index.column() != column || isHidden(index.row()))
              return QRect();
          executePostedLayout();
          return viewItemRect(indexToListViewItem(index));
      }
  
      void viewUpdateGeometries() { q_func()->updateGeometries(); }
  
  
      QRect mapToViewport(const QRect &rect, bool extend = true) const;
  
      QModelIndex closestIndex(const QRect &target, const QVector<QModelIndex> &candidates) const;
      QSize itemSize(const QStyleOptionViewItem &option, const QModelIndex &index) const;
  
      bool selectionAllowed(const QModelIndex &index) const
          { if (viewMode == QListView::ListMode && !showElasticBand) return index.isValid(); return true; }
  
      int horizontalScrollToValue(const QModelIndex &index, const QRect &rect, QListView::ScrollHint hint) const;
      int verticalScrollToValue(const QModelIndex &index, const QRect &rect, QListView::ScrollHint hint) const;
  
      QItemSelection selection(const QRect &rect) const;
      void selectAll(QItemSelectionModel::SelectionFlags command);
  
  #ifndef QT_NO_DRAGANDDROP
      virtual QAbstractItemView::DropIndicatorPosition position(const QPoint &pos, const QRect &rect, const QModelIndex &idx) const;
      bool dropOn(QDropEvent *event, int *row, int *col, QModelIndex *index);
  #endif
  
      inline void setGridSize(const QSize &size) { grid = size; }
      inline QSize gridSize() const { return grid; }
      inline void setWrapping(bool b) { wrap = b; }
      inline bool isWrapping() const { return wrap; }
      inline void setSpacing(int s) { space = s; }
      inline int spacing() const { return space; }
      inline void setSelectionRectVisible(bool visible) { showElasticBand = visible; }
      inline bool isSelectionRectVisible() const { return showElasticBand; }
  
      inline QModelIndex modelIndex(int row) const { return model->index(row, column, root); }
      inline bool isHidden(int row) const {
          QModelIndex idx = model->index(row, 0, root);
          return isPersistent(idx) && hiddenRows.contains(idx);
      }
      inline bool isHiddenOrDisabled(int row) const { return isHidden(row) || !isIndexEnabled(modelIndex(row)); }
  
      inline void removeCurrentAndDisabled(QVector<QModelIndex> *indexes, const QModelIndex &current) const {
          QVector<QModelIndex>::iterator it = indexes->begin();
          while (it != indexes->end()) {
              if (!isIndexEnabled(*it) || (*it) == current)
                  indexes->erase(it);
              else
                  ++it;
          }
      }
  
      QStyleOptionViewItem viewOptions() const;
  
      void scrollElasticBandBy(int dx, int dy);
  
      QItemViewPaintPairs draggablePaintPairs(const QModelIndexList &indexes, QRect *r) const;
  
      void emitIndexesMoved(const QModelIndexList &indexes) { emit q_func()->indexesMoved(indexes); }
  
  
      QCommonListViewBase *commonListView;
  
      // ### FIXME: see if we can move the members into the dynamic/static classes
  
      bool wrap;
      int space;
      QSize grid;
  
      QListView::Flow flow;
      QListView::Movement movement;
      QListView::ResizeMode resizeMode;
      QListView::LayoutMode layoutMode;
      QListView::ViewMode viewMode;
  
      // the properties controlling the
      // icon- or list-view modes
      enum ModeProperties {
          Wrap = 1,
          Spacing = 2,
          GridSize = 4,
          Flow = 8,
          Movement = 16,
          ResizeMode = 32,
          SelectionRectVisible = 64
      };
  
      uint modeProperties : 8;
  
      QRect layoutBounds;
  
      // timers
      QBasicTimer batchLayoutTimer;
  
      // used for hidden items
      QSet<QPersistentModelIndex> hiddenRows;
  
      int column;
      bool uniformItemSizes;
      mutable QSize cachedItemSize;
      int batchSize;
  
      QRect elasticBand;
      bool showElasticBand;
  };
  
  // inline implementations
  
  inline int QCommonListViewBase::spacing() const { return dd->spacing(); }
  inline bool QCommonListViewBase::isWrapping() const { return dd->isWrapping(); }
  inline QSize QCommonListViewBase::gridSize() const { return dd->gridSize(); }
  inline QListView::Flow QCommonListViewBase::flow() const { return dd->flow; }
  inline QListView::Movement QCommonListViewBase::movement() const { return dd->movement; }
  
  inline QPoint QCommonListViewBase::offset() const { return dd->offset(); }
  inline QPoint QCommonListViewBase::pressedPosition() const { return dd->pressedPosition; }
  inline bool QCommonListViewBase::uniformItemSizes() const { return dd->uniformItemSizes; }
  inline int QCommonListViewBase::column() const { return dd->column; }
  
  inline QScrollBar *QCommonListViewBase::verticalScrollBar() const { return qq->verticalScrollBar(); }
  inline QScrollBar *QCommonListViewBase::horizontalScrollBar() const { return qq->horizontalScrollBar(); }
  inline QListView::ScrollMode QCommonListViewBase::verticalScrollMode() const { return qq->verticalScrollMode(); }
  inline QListView::ScrollMode QCommonListViewBase::horizontalScrollMode() const { return qq->horizontalScrollMode(); }
  
  inline QModelIndex QCommonListViewBase::modelIndex(int row) const
      { return dd->model->index(row, dd->column, dd->root); }
  inline int QCommonListViewBase::rowCount() const { return dd->model->rowCount(dd->root); }
  
  inline QStyleOptionViewItem QCommonListViewBase::viewOptions() const { return dd->viewOptions(); }
  inline QWidget *QCommonListViewBase::viewport() const { return dd->viewport; }
  inline QRect QCommonListViewBase::clipRect() const { return dd->clipRect(); }
  
  inline QSize QCommonListViewBase::cachedItemSize() const { return dd->cachedItemSize; }
  inline QRect QCommonListViewBase::viewItemRect(const QListViewItem &item) const { return dd->viewItemRect(item); }
  inline QSize QCommonListViewBase::itemSize(const QStyleOptionViewItem &opt, const QModelIndex &idx) const
      { return dd->itemSize(opt, idx); }
  
  inline QAbstractItemDelegate *QCommonListViewBase::delegate(const QModelIndex &idx) const
      { return dd->delegateForIndex(idx); }
  
  inline bool QCommonListViewBase::isHidden(int row) const { return dd->isHidden(row); }
  inline int QCommonListViewBase::hiddenCount() const { return dd->hiddenRows.count(); }
  
  inline bool QCommonListViewBase::isRightToLeft() const { return qq->isRightToLeft(); }
  
  QT_END_NAMESPACE
  
  #endif // QT_NO_LISTVIEW
  
  #endif // QLISTVIEW_P_H
  