include/wx/selstore.h

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/selstore.h
   3 // Purpose:     wxSelectionStore stores selected items in a control
   4 // Author:      Vadim Zeitlin
   5 // Modified by:
   6 // Created:     08.06.03 (extracted from src/generic/listctrl.cpp)
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 2000-2003 Vadim Zeitlin <vadim@wxwindows.org>
   9 // Licence:     wxWindows licence
  10 ///////////////////////////////////////////////////////////////////////////////
  11
  12 #ifndef _WX_SELSTORE_H_
  13 #define _WX_SELSTORE_H_
  14
  15 #include "wx/dynarray.h"
  16
  17 // ----------------------------------------------------------------------------
  18 // wxSelectedIndices is just a sorted array of indices
  19 // ----------------------------------------------------------------------------
  20
  21 inline int CMPFUNC_CONV wxSizeTCmpFn(size_t n1, size_t n2) { return n1 - n2; }
  22
  23 WX_DEFINE_SORTED_EXPORTED_ARRAY_CMP_LONG(size_t,
  24                                          wxSizeTCmpFn,
  25                                          wxSelectedIndices);
  26
  27 // ----------------------------------------------------------------------------
  28 // wxSelectionStore is used to store the selected items in the virtual
  29 // controls, i.e. it is well suited for storing even when the control contains
  30 // a huge (practically infinite) number of items.
  31 //
  32 // Of course, internally it still has to store the selected items somehow (as
  33 // an array currently) but the advantage is that it can handle the selection
  34 // of all items (common operation) efficiently and that it could be made even
  35 // smarter in the future (e.g. store the selections as an array of ranges +
  36 // individual items) without changing its API.
  37 // ----------------------------------------------------------------------------
  38
  39 class WXDLLEXPORT wxSelectionStore
  40 {
  41 public:
  42     wxSelectionStore() : m_itemsSel(wxSizeTCmpFn) { Init(); }
  43
  44     // set the total number of items we handle
  45     void SetItemCount(size_t count) { m_count = count; }
  46
  47     // special case of SetItemCount(0)
  48     void Clear() { m_itemsSel.Clear(); m_count = 0; m_defaultState = FALSE; }
  49
  50     // must be called when a new item is inserted/added
  51     void OnItemAdd(size_t WXUNUSED(item)) { wxFAIL_MSG( _T("TODO") ); }
  52
  53     // must be called when an item is deleted
  54     void OnItemDelete(size_t item);
  55
  56     // select one item, use SelectRange() insted if possible!
  57     //
  58     // returns true if the items selection really changed
  59     bool SelectItem(size_t item, bool select = TRUE);
  60
  61     // select the range of items
  62     //
  63     // return true and fill the itemsChanged array with the indices of items
  64     // which have changed state if "few" of them did, otherwise return false
  65     // (meaning that too many items changed state to bother counting them
  66     // individually)
  67     bool SelectRange(size_t itemFrom, size_t itemTo,
  68                      bool select = TRUE,
  69                      wxArrayInt *itemsChanged = NULL);
  70
  71     // return true if the given item is selected
  72     bool IsSelected(size_t item) const;
  73
  74     // return the total number of selected items
  75     size_t GetSelectedCount() const
  76     {
  77         return m_defaultState ? m_count - m_itemsSel.GetCount()
  78                               : m_itemsSel.GetCount();
  79     }
  80
  81 private:
  82     // (re)init
  83     void Init() { m_defaultState = FALSE; }
  84
  85     // the total number of items we handle
  86     size_t m_count;
  87
  88     // the default state: normally, FALSE (i.e. off) but maybe set to TRUE if
  89     // there are more selected items than non selected ones - this allows to
  90     // handle selection of all items efficiently
  91     bool m_defaultState;
  92
  93     // the array of items whose selection state is different from default
  94     wxSelectedIndices m_itemsSel;
  95
  96     DECLARE_NO_COPY_CLASS(wxSelectionStore)
  97 };
  98
  99
 100 #endif // _WX_SELSTORE_H_
 101