+#ifdef __GNUG__
+ #pragma interface "dataobjbase.h"
+#endif
+
+// ----------------------------------------------------------------------------
+// headers
+// ----------------------------------------------------------------------------
+
+#include "wx/defs.h"
+#include "wx/string.h"
+#include "wx/bitmap.h"
+#include "wx/list.h"
+
+// ============================================================================
+/*
+ Generic data transfer related classes. The class hierarchy is as follows:
+
+ - wxDataObject-
+ / \
+ / \
+ wxDataObjectSimple wxDataObjectComposite
+ / | \
+ / | \
+ wxTextDataObject | wxBitmapDataObject
+ |
+ wxCustomDataObject
+
+*/
+// ============================================================================
+
+// ----------------------------------------------------------------------------
+// wxDataFormat class is declared in platform-specific headers: it represents
+// a format for data which may be either one of the standard ones (text,
+// bitmap, ...) or a custom one which is then identified by a unique string.
+// ----------------------------------------------------------------------------
+
+/* the class interface looks like this (pseudo code):
+
+class wxDataFormat
+{
+public:
+ typedef <integral type> NativeFormat;
+
+ wxDataFormat(NativeFormat format = wxDF_INVALID);
+ wxDataFormat(const wxChar *format);
+
+ wxDataFormat& operator=(NativeFormat format);
+ wxDataFormat& operator=(const wxDataFormat& format);
+
+ bool operator==(NativeFormat format) const;
+ bool operator!=(NativeFormat format) const;
+
+ void SetType(NativeFormat format);
+ NativeFormat GetType() const;
+
+ wxString GetId() const;
+ void SetId(const wxChar *format);
+};
+
+*/
+
+#if defined(__WXMSW__)
+ #include "wx/msw/ole/dataform.h"
+#elif defined(__WXMOTIF__)
+ #include "wx/motif/dataform.h"
+#elif defined(__WXGTK__)
+ #include "wx/gtk/dataform.h"
+#elif defined(__WXMAC__)
+ #include "wx/mac/dataform.h"
+#elif defined(__WXPM__)
+ #include "wx/os2/dataform.h"
+#endif
+
+// the value for default argument to some functions (corresponds to
+// wxDF_INVALID)
+extern WXDLLEXPORT const wxDataFormat& wxFormatInvalid;
+
+// ----------------------------------------------------------------------------
+// wxDataObject represents a piece of data which knows which formats it
+// supports and knows how to render itself in each of them - GetDataHere(),
+// and how to restore data from the buffer (SetData()).
+//
+// Although this class may be used directly (i.e. custom classes may be
+// derived from it), in many cases it might be simpler to use either
+// wxDataObjectSimple or wxDataObjectComposite classes.
+//
+// A data object may be "read only", i.e. support only GetData() functions or
+// "read-write", i.e. support both GetData() and SetData() (in principle, it
+// might be "write only" too, but this is rare). Moreover, it doesn't have to
+// support the same formats in Get() and Set() directions: for example, a data
+// object containing JPEG image might accept BMPs in GetData() because JPEG
+// image may be easily transformed into BMP but not in SetData(). Accordingly,
+// all methods dealing with formats take an additional "direction" argument
+// which is either SET or GET and which tells the function if the format needs
+// to be supported by SetData() or GetDataHere().
+// ----------------------------------------------------------------------------
+
+class WXDLLEXPORT wxDataObjectBase
+{
+public:
+ enum Direction
+ {
+ Get = 0x01, // format is supported by GetDataHere()
+ Set = 0x02, // format is supported by SetData()
+ Both = 0x03 // format is supported by both (unused currently)
+ };
+
+ // this class is polymorphic, hence it needs a virtual dtor
+ virtual ~wxDataObjectBase();
+
+ // get the best suited format for rendering our data
+ virtual wxDataFormat GetPreferredFormat(Direction dir = Get) const = 0;
+
+ // get the number of formats we support
+ virtual size_t GetFormatCount(Direction dir = Get) const = 0;
+
+ // return all formats in the provided array (of size GetFormatCount())
+ virtual void GetAllFormats(wxDataFormat *formats,
+ Direction dir = Get) const = 0;
+
+ // get the (total) size of data for the given format
+ virtual size_t GetDataSize(const wxDataFormat& format) const = 0;
+
+ // copy raw data (in the specified format) to the provided buffer, return
+ // TRUE if data copied successfully, FALSE otherwise
+ virtual bool GetDataHere(const wxDataFormat& format, void *buf) const = 0;
+
+ // get data from the buffer of specified length (in the given format),
+ // return TRUE if the data was read successfully, FALSE otherwise
+ virtual bool SetData(const wxDataFormat& WXUNUSED(format),
+ size_t WXUNUSED(len), const void * WXUNUSED(buf))
+ {
+ return FALSE;
+ }
+
+ // returns TRUE if this format is supported
+ bool IsSupported(const wxDataFormat& format, Direction dir = Get) const;
+};
+
+// ----------------------------------------------------------------------------
+// include the platform-specific declarations of wxDataObject
+// ----------------------------------------------------------------------------
+
projects / wxWidgets.git / blobdiff