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