X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/1de8d512b7c844d67b2dab36addc89868e68c9b6..b02dd12239c8a59b9a545d9fcb04974f8ad02c6b:/include/wx/gdiobj.h diff --git a/include/wx/gdiobj.h b/include/wx/gdiobj.h index 5c9747694a..0c251cc9d6 100644 --- a/include/wx/gdiobj.h +++ b/include/wx/gdiobj.h @@ -20,18 +20,44 @@ // the same native GDI object // ---------------------------------------------------------------------------- -class WXDLLIMPEXP_CORE wxGDIRefData: public wxObjectRefData { }; +class WXDLLIMPEXP_CORE wxGDIRefData : public wxObjectRefData +{ +public: + // Default ctor which needs to be defined just because we use + // wxDECLARE_NO_COPY_CLASS() below. + wxGDIRefData() { } + + // override this in the derived classes to check if this data object is + // really fully initialized + virtual bool IsOk() const { return true; } + +private: + wxDECLARE_NO_COPY_CLASS(wxGDIRefData); +}; // ---------------------------------------------------------------------------- -// wxGDIObject +// wxGDIObject: base class for bitmaps, pens, brushes, ... // ---------------------------------------------------------------------------- -class WXDLLIMPEXP_CORE wxGDIObject: public wxObject +class WXDLLIMPEXP_CORE wxGDIObject : public wxObject { public: + // checks if the object can be used + virtual bool IsOk() const + { + // the cast here is safe because the derived classes always create + // wxGDIRefData objects + return m_refData && static_cast(m_refData)->IsOk(); + } + + // don't use in the new code, use IsOk() instead bool IsNull() const { return m_refData == NULL; } -#if defined(__WXMSW__) || defined(__WXOS2__) || defined(__WXPALMOS__) + // older version, for backwards compatibility only (but not deprecated + // because it's still widely used) + bool Ok() const { return IsOk(); } + +#if defined(__WXMSW__) || defined(__WXPM__) // Creates the resource virtual bool RealizeResource() { return false; } @@ -42,10 +68,26 @@ public: // Returns handle. virtual WXHANDLE GetResourceHandle() const { return 0; } -#endif // defined(__WXMSW__) || defined(__WXOS2__) +#endif // defined(__WXMSW__) || defined(__WXPM__) + +protected: + // replace base class functions using wxObjectRefData with our own which + // use wxGDIRefData to ensure that we always work with data objects of the + // correct type (i.e. derived from wxGDIRefData) + virtual wxObjectRefData *CreateRefData() const + { + return CreateGDIRefData(); + } + + virtual wxObjectRefData *CloneRefData(const wxObjectRefData *data) const + { + return CloneGDIRefData(static_cast(data)); + } + + virtual wxGDIRefData *CreateGDIRefData() const = 0; + virtual wxGDIRefData *CloneGDIRefData(const wxGDIRefData *data) const = 0; DECLARE_DYNAMIC_CLASS(wxGDIObject) }; -#endif - // _WX_GDIOBJ_H_BASE_ +#endif // _WX_GDIOBJ_H_BASE_