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@wxwidgets.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 wxUIntCmp(unsigned n1, unsigned n2)
  22 {
  23     return (int)(n1 - n2);
  24 }
  25
  26 WX_DEFINE_SORTED_EXPORTED_ARRAY_CMP_INT(unsigned, wxUIntCmp, wxSelectedIndices);
  27
  28 // ----------------------------------------------------------------------------
  29 // wxSelectionStore is used to store the selected items in the virtual
  30 // controls, i.e. it is well suited for storing even when the control contains
  31 // a huge (practically infinite) number of items.
  32 //
  33 // Of course, internally it still has to store the selected items somehow (as
  34 // an array currently) but the advantage is that it can handle the selection
  35 // of all items (common operation) efficiently and that it could be made even
  36 // smarter in the future (e.g. store the selections as an array of ranges +
  37 // individual items) without changing its API.
  38 // ----------------------------------------------------------------------------
  39
  40 class WXDLLIMPEXP_CORE wxSelectionStore
  41 {
  42 public:
  43     wxSelectionStore() : m_itemsSel(wxUIntCmp) { Init(); }
  44
  45     // set the total number of items we handle
  46     void SetItemCount(unsigned count);
  47
  48     // special case of SetItemCount(0)
  49     void Clear() { m_itemsSel.Clear(); m_count = 0; m_defaultState = false; }
  50
  51     // must be called when a new item is inserted/added
  52     void OnItemAdd(unsigned WXUNUSED(item)) { wxFAIL_MSG( wxT("TODO") ); }
  53
  54     // must be called when an item is deleted
  55     void OnItemDelete(unsigned item);
  56
  57     // select one item, use SelectRange() insted if possible!
  58     //
  59     // returns true if the items selection really changed
  60     bool SelectItem(unsigned item, bool select = true);
  61
  62     // select the range of items (inclusive)
  63     //
  64     // return true and fill the itemsChanged array with the indices of items
  65     // which have changed state if "few" of them did, otherwise return false
  66     // (meaning that too many items changed state to bother counting them
  67     // individually)
  68     bool SelectRange(unsigned itemFrom, unsigned itemTo,
  69                      bool select = true,
  70                      wxArrayInt *itemsChanged = NULL);
  71
  72     // return true if the given item is selected
  73     bool IsSelected(unsigned item) const;
  74
  75     // return the total number of selected items
  76     unsigned GetSelectedCount() const
  77     {
  78         return m_defaultState ? m_count - m_itemsSel.GetCount()
  79                               : m_itemsSel.GetCount();
  80     }
  81
  82 private:
  83     // (re)init
  84     void Init() { m_defaultState = false; }
  85
  86     // the total number of items we handle
  87     unsigned m_count;
  88
  89     // the default state: normally, false (i.e. off) but maybe set to true if
  90     // there are more selected items than non selected ones - this allows to
  91     // handle selection of all items efficiently
  92     bool m_defaultState;
  93
  94     // the array of items whose selection state is different from default
  95     wxSelectedIndices m_itemsSel;
  96
  97     wxDECLARE_NO_COPY_CLASS(wxSelectionStore);
  98 };
  99
 100 #endif // _WX_SELSTORE_H_
 101