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