docs/latex/wx/varvscrollhelper.tex

   1 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   2 %% Name:        varvscrollhelper.tex
   3 %% Purpose:     wxVarVScrollHelper Documentation
   4 %% Author:      Bryan Petty
   5 %% Modified by:
   6 %% Created:     2007-04-04
   7 %% RCS-ID:      $Id$
   8 %% Copyright:   (c) 2007 wxWidgets Team
   9 %% License:     wxWindows Licence
  10 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  11
  12 \section{\class{wxVarVScrollHelper}}\label{wxvarvscrollhelper}
  13
  14 This class provides functions wrapping the
  15 \helpref{wxVarScrollHelperBase}{wxvarscrollhelperbase} class, targeted for
  16 vertical-specific scrolling using \helpref{wxVScrolledWindow}{wxvscrolledwindow}.
  17
  18 Like wxVarScrollHelperBase, this class is mostly only useful to those classes
  19 built into wxWidgets deriving from here, and this documentation is mostly
  20 only provided for referencing those functions provided. You will likely want
  21 to derive your window from wxVScrolledWindow rather than from here directly.
  22
  23 \wxheading{Derived from}
  24
  25 \helpref{wxVarScrollHelperBase}{wxvarscrollhelperbase}
  26
  27 \wxheading{Include files}
  28
  29 <wx/vscroll.h>
  30
  31 \wxheading{Library}
  32
  33 \helpref{wxCore}{librarieslist}
  34
  35 \wxheading{See also}
  36
  37 \helpref{wxHScrolledWindow}{wxhscrolledwindow},
  38 \rtfsp\helpref{wxHVScrolledWindow}{wxhvscrolledwindow},
  39 \rtfsp\helpref{wxVScrolledWindow}{wxvscrolledwindow}
  40
  41 \latexignore{\rtfignore{\wxheading{Members}}}
  42
  43
  44 \membersection{wxVarVScrollHelper::wxVarVScrollHelper}\label{wxvarvscrollhelperwxvarvscrollhelper}
  45
  46 \func{}{wxVarVScrollHelper}{\param{wxWindow* }{winToScroll}}
  47
  48 Constructor taking the target window to be scrolled by this helper class.
  49 This will attach scroll event handlers to the target window to catch and
  50 handle scroll events appropriately.
  51
  52
  53 \membersection{wxVarVScrollHelper::EstimateTotalHeight}\label{wxvarvscrollhelperestimatetotalheight}
  54
  55 \constfunc{virtual wxCoord}{EstimateTotalHeight}{\void}
  56
  57 This class forwards calls from
  58 \helpref{wxVarScrollHelperBase::EstimateTotalSize}{wxvarscrollhelperbaseestimatetotalsize}
  59 to this function so derived classes can override either just the height or
  60 the width estimation, or just estimate both differently if desired in any
  61 \helpref{wxHVScrolledWindow}{wxhvscrolledwindow} derived class.
  62
  63 Please note that this function will not be called if {\tt EstimateTotalSize()}
  64 is overridden in your derived class.
  65
  66
  67 \membersection{wxVarVScrollHelper::GetRowCount}\label{wxvarvscrollhelpergetrowcount}
  68
  69 \constfunc{size\_t}{GetRowCount}{\void}
  70
  71 Returns the number of rows the target window contains.
  72
  73 \wxheading{See also}
  74
  75 \helpref{SetRowCount()}{wxvarvscrollhelpersetrowcount}
  76
  77
  78 \membersection{wxVarVScrollHelper::GetVisibleRowsBegin}\label{wxvarvscrollhelpergetvisiblerowsbegin}
  79
  80 \constfunc{size\_t}{GetVisibleRowsBegin}{\void}
  81
  82 Returns the index of the first visible row based on the scroll position.
  83
  84
  85 \membersection{wxVarVScrollHelper::GetVisibleRowsEnd}\label{wxvarvscrollhelpergetvisiblerowsend}
  86
  87 \constfunc{size\_t}{GetVisibleRowsEnd}{\void}
  88
  89 Returns the index of the last visible row based on the scroll position. This
  90 includes the last row even if it is only partially visible.
  91
  92
  93 \membersection{wxVarVScrollHelper::IsRowVisible}\label{wxvarvscrollhelperisrowvisible}
  94
  95 \constfunc{bool}{IsRowVisible}{\param{size\_t }{row}}
  96
  97 Returns {\tt true} if the given row is currently visible (even if only
  98 partially visible) or {\tt false} otherwise.
  99
 100
 101 \membersection{wxVarVScrollHelper::OnGetRowHeight}\label{wxvarvscrollhelperongetrowheight}
 102
 103 \constfunc{virtual wxCoord}{OnGetRowHeight}{\param{size\_t }{row}}
 104
 105 This function must be overridden in the derived class, and should return the
 106 height of the given row in pixels.
 107
 108
 109 \membersection{wxVarVScrollHelper::OnGetRowsHeightHint}\label{wxvarvscrollhelperongetrowsheighthint}
 110
 111 \constfunc{virtual void}{OnGetRowsHeightHint}{\param{size\_t }{rowMin}, \param{size\_t }{rowMax}}
 112
 113 This function doesn't have to be overridden but it may be useful to do so if
 114 calculating the rows' sizes is a relatively expensive operation as it gives
 115 your code a chance to calculate several of them at once and cache the result
 116 if necessary.
 117
 118 {\tt OnGetRowsHeightHint()} is normally called just before
 119 \helpref{OnGetRowHeight()}{wxvarvscrollhelperongetrowheight} but you
 120 shouldn't rely on the latter being called for all rows in the interval
 121 specified here. It is also possible that OnGetRowHeight() will be called for
 122 units outside of this interval, so this is really just a hint, not a promise.
 123
 124 Finally, note that rowMin is inclusive, while rowMax is exclusive.
 125
 126
 127 \membersection{wxVarVScrollHelper::RefreshRow}\label{wxvarvscrollhelperrefreshrow}
 128
 129 \func{virtual void}{RefreshRow}{\param{size\_t }{row}}
 130
 131 Triggers a refresh for just the given row's area of the window if it's visible.
 132
 133
 134 \membersection{wxVarVScrollHelper::RefreshRows}\label{wxvarvscrollhelperrefreshrows}
 135
 136 \func{virtual void}{RefreshRows}{\param{size\_t }{from}, \param{size\_t }{to}}
 137
 138 Triggers a refresh for the area between the specified range of rows given
 139 (inclusively).
 140
 141
 142 \membersection{wxVarVScrollHelper::ScrollRowPages}\label{wxvarvscrollhelperscrollrowpages}
 143
 144 \func{virtual bool}{ScrollRowPages}{\param{int }{pages}}
 145
 146 Scroll by the specified number of pages which may be positive (to scroll down)
 147 or negative (to scroll up).
 148
 149
 150 \membersection{wxVarVScrollHelper::ScrollRows}\label{wxvarvscrollhelperscrollrows}
 151
 152 \func{virtual bool}{ScrollRows}{\param{int }{rows}}
 153
 154 Scroll by the specified number of rows which may be positive (to scroll down)
 155 or negative (to scroll up).
 156
 157 Returns {\tt true} if the window was scrolled, {\tt false} otherwise (for
 158 example, if we're trying to scroll down but we are already showing the last
 159 row).
 160
 161
 162 \membersection{wxVarVScrollHelper::ScrollToRow}\label{wxvarvscrollhelperscrolltorow}
 163
 164 \func{bool}{ScrollToRow}{\param{size\_t }{row}}
 165
 166 Scroll to the specified row. It will become the first visible row in the window.
 167
 168 Returns {\tt true} if we scrolled the window, {\tt false} if nothing was done.
 169
 170
 171 \membersection{wxVarVScrollHelper::SetRowCount}\label{wxvarvscrollhelpersetrowcount}
 172
 173 \func{void}{SetRowCount}{\param{size\_t }{rowCount}}
 174
 175 Set the number of rows the window contains. The derived class must provide the
 176 heights for all rows with indices up to the one given here in it's
 177 \helpref{OnGetRowHeight()}{wxvarvscrollhelperongetrowheight} implementation.
 178
 179 \wxheading{See also}
 180
 181 \helpref{GetRowCount()}{wxvarvscrollhelpergetrowcount}
 182