include/wx/wrapsizer.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/wrapsizer.h
   3 // Purpose:     provide wrapping sizer for layout (wxWrapSizer)
   4 // Author:      Arne Steinarson
   5 // Created:     2008-05-08
   6 // RCS-ID:      $Id$
   7 // Copyright:   (c) Arne Steinarson
   8 // Licence:     wxWindows licence
   9 /////////////////////////////////////////////////////////////////////////////
  10
  11 #ifndef _WX_WRAPSIZER_H_
  12 #define _WX_WRAPSIZER_H_
  13
  14 #include "wx/sizer.h"
  15
  16 // flags for wxWrapSizer
  17 enum
  18 {
  19     wxEXTEND_LAST_ON_EACH_LINE = 1,
  20     // don't leave spacers in the beginning of a new row
  21     wxREMOVE_LEADING_SPACES = 2,
  22
  23     wxWRAPSIZER_DEFAULT_FLAGS = wxEXTEND_LAST_ON_EACH_LINE |
  24                                 wxREMOVE_LEADING_SPACES
  25 };
  26
  27 // ----------------------------------------------------------------------------
  28 // A box sizer that can wrap items on several lines when sum of widths exceed
  29 // available line width.
  30 // ----------------------------------------------------------------------------
  31
  32 class WXDLLEXPORT wxWrapSizer : public wxBoxSizer
  33 {
  34 public:
  35     wxWrapSizer(int orient = wxHORIZONTAL, int flags = wxWRAPSIZER_DEFAULT_FLAGS);
  36     virtual ~wxWrapSizer();
  37
  38     // override base class virtual methods
  39     virtual wxSize CalcMin();
  40     virtual void RecalcSizes();
  41
  42     virtual bool InformFirstDirection(int direction,
  43                                       int size,
  44                                       int availableOtherDir);
  45
  46 protected:
  47     // This method is called to decide if an item represents empty space or
  48     // not. We do this to avoid having space-only items first or last on a
  49     // wrapped line (left alignment).
  50     //
  51     // By default only spacers are considered to be empty items but a derived
  52     // class may override this item if some other kind of sizer elements should
  53     // be also considered empty for some reason.
  54     virtual bool IsSpaceItem(wxSizerItem *item) const
  55     {
  56         return item->IsSpacer();
  57     }
  58
  59     // helpers of CalcMin()
  60     void CalcMinFromMinor(int totMinor);
  61     void CalcMinFromMajor(int totMajor);
  62     void CalcMinUsingCurrentLayout();
  63     void CalcMinFittingSize(const wxSize& szBoundary);
  64     void CalcMaxSingleItemSize();
  65
  66     // temporarily change the proportion of the last item of the N-th row to
  67     // extend to the end of line if the appropriate flag is set
  68     void AdjustLastRowItemProp(size_t n, wxSizerItem *itemLast);
  69
  70     // remove all the items from m_rows
  71     void ClearRows();
  72
  73     // return the N-th row sizer from m_rows creating it if necessary
  74     wxSizer *GetRowSizer(size_t n);
  75
  76     // should be called after completion of each row
  77     void FinishRow(size_t n, int rowMajor, int rowMinor, wxSizerItem *itemLast);
  78
  79
  80     const int m_flags;       // Flags specified in the ctor
  81
  82     int m_dirInform;         // Direction for size information
  83     int m_availSize;         // Size available in m_dirInform direction
  84     int m_availableOtherDir; // Size available in the other direction
  85     bool m_lastUsed;         // Indicates whether value from InformFirst... has
  86                              //  been used yet
  87
  88     // The sizes below are computed by RecalcSizes(), i.e. they don't have
  89     // valid values during the initial call to CalcMin() and they are only
  90     // valid for the current layout (i.e. the current number of rows)
  91     int m_minSizeMinor;      // Min size in minor direction
  92     int m_maxSizeMajor;      // Size of longest row
  93     int m_minItemMajor;      // Size of smallest item in major direction
  94
  95     wxBoxSizer m_rows;       // Sizer containing multiple rows of our items
  96
  97     DECLARE_DYNAMIC_CLASS_NO_COPY(wxWrapSizer)
  98 };
  99
 100 #endif // _WX_WRAPSIZER_H_