docs/latex/wx/metafile.tex

   1 \section{\class{wxMetafile}}\label{wxmetafile}
   2
   3 A {\bf wxMetafile} represents the MS Windows metafile object, so metafile
   4 operations have no effect in X. In wxWidgets, only sufficient functionality
   5 has been provided for copying a graphic to the clipboard; this may be extended
   6 in a future version. Presently, the only way of creating a metafile
   7 is to use a wxMetafileDC.
   8
   9 \wxheading{Derived from}
  10
  11 \helpref{wxObject}{wxobject}
  12
  13 \wxheading{Include files}
  14
  15 <wx/metafile.h>
  16
  17 \wxheading{See also}
  18
  19 \helpref{wxMetafileDC}{wxmetafiledc}
  20
  21 \latexignore{\rtfignore{\wxheading{Members}}}
  22
  23 \membersection{wxMetafile::wxMetafile}\label{wxmetafilector}
  24
  25 \func{}{wxMetafile}{\param{const wxString\& }{filename = ""}}
  26
  27 Constructor. If a filename is given, the Windows disk metafile is
  28 read in. Check whether this was performed successfully by
  29 using the \helpref{wxMetafile:IsOk}{wxmetafileisok} member.
  30
  31 \membersection{wxMetafile::\destruct{wxMetafile}}\label{wxmetafiledtor}
  32
  33 \func{}{\destruct{wxMetafile}}{\void}
  34
  35 Destructor.
  36 See \helpref{reference-counted object destruction}{refcountdestruct} for more info.
  37
  38 \membersection{wxMetafile::IsOk}\label{wxmetafileisok}
  39
  40 \func{bool}{Ok}{\void}
  41
  42 Returns true if the metafile is valid.
  43
  44 \membersection{wxMetafile::Play}\label{wxmetafileplay}
  45
  46 \func{bool}{Play}{\param{wxDC *}{dc}}
  47
  48 Plays the metafile into the given device context, returning
  49 true if successful.
  50
  51 \membersection{wxMetafile::SetClipboard}\label{wxmetafilesetclipboard}
  52
  53 \func{bool}{SetClipboard}{\param{int}{ width = 0}, \param{int}{ height = 0}}
  54
  55 Passes the metafile data to the clipboard. The metafile can no longer be
  56 used for anything, but the wxMetafile object must still be destroyed by
  57 the application.
  58
  59 Below is a example of metafile, metafile device context and clipboard use
  60 from the {\tt hello.cpp} example. Note the way the metafile dimensions
  61 are passed to the clipboard, making use of the device context's ability
  62 to keep track of the maximum extent of drawing commands.
  63
  64 \begin{verbatim}
  65   wxMetafileDC dc;
  66   if (dc.Ok())
  67   {
  68     Draw(dc, false);
  69     wxMetafile *mf = dc.Close();
  70     if (mf)
  71     {
  72       bool success = mf->SetClipboard((int)(dc.MaxX() + 10), (int)(dc.MaxY() + 10));
  73       delete mf;
  74     }
  75   }
  76 \end{verbatim}
  77
  78 \section{\class{wxMetafileDC}}\label{wxmetafiledc}
  79
  80 This is a type of device context that allows a metafile object to be
  81 created (Windows only), and has most of the characteristics of a normal
  82 \rtfsp{\bf wxDC}. The \helpref{wxMetafileDC::Close}{wxmetafiledcclose} member must be called after drawing into the
  83 device context, to return a metafile. The only purpose for this at
  84 present is to allow the metafile to be copied to the clipboard (see \helpref{wxMetafile}{wxmetafile}).
  85
  86 Adding metafile capability to an application should be easy if you
  87 already write to a wxDC; simply pass the wxMetafileDC to your drawing
  88 function instead. You may wish to conditionally compile this code so it
  89 is not compiled under X (although no harm will result if you leave it
  90 in).
  91
  92 Note that a metafile saved to disk is in standard Windows metafile format,
  93 and cannot be imported into most applications. To make it importable,
  94 call the function \helpref{::wxMakeMetafilePlaceable}{wxmakemetafileplaceable} after
  95 closing your disk-based metafile device context.
  96
  97 \wxheading{Derived from}
  98
  99 \helpref{wxDC}{wxdc}\\
 100 \helpref{wxObject}{wxobject}
 101
 102 \wxheading{Include files}
 103
 104 <wx/metafile.h>
 105
 106 \wxheading{See also}
 107
 108 \helpref{wxMetafile}{wxmetafile}, \helpref{wxDC}{wxdc}
 109
 110 \latexignore{\rtfignore{\wxheading{Members}}}
 111
 112 \membersection{wxMetafileDC::wxMetafileDC}\label{wxmetafiledcctor}
 113
 114 \func{}{wxMetafileDC}{\param{const wxString\& }{filename = ""}}
 115
 116 Constructor. If no filename is passed, the metafile is created
 117 in memory.
 118
 119 \membersection{wxMetafileDC::\destruct{wxMetafileDC}}\label{wxmetafiledcdtor}
 120
 121 \func{}{\destruct{wxMetafileDC}}{\void}
 122
 123 Destructor.
 124
 125 \membersection{wxMetafileDC::Close}\label{wxmetafiledcclose}
 126
 127 \func{wxMetafile *}{Close}{\void}
 128
 129 This must be called after the device context is finished with. A
 130 metafile is returned, and ownership of it passes to the calling
 131 application (so it should be destroyed explicitly).
 132