| 1 | ///////////////////////////////////////////////////////////////////////////// |
| 2 | // Name: wx/gdiobj.h |
| 3 | // Purpose: wxGDIObject base header |
| 4 | // Author: Julian Smart |
| 5 | // Modified by: |
| 6 | // Created: |
| 7 | // Copyright: (c) Julian Smart |
| 8 | // RCS-ID: $Id$ |
| 9 | // Licence: wxWindows Licence |
| 10 | ///////////////////////////////////////////////////////////////////////////// |
| 11 | |
| 12 | #ifndef _WX_GDIOBJ_H_BASE_ |
| 13 | #define _WX_GDIOBJ_H_BASE_ |
| 14 | |
| 15 | #include "wx/object.h" |
| 16 | |
| 17 | // ---------------------------------------------------------------------------- |
| 18 | // wxGDIRefData is the base class for wxXXXData structures which contain the |
| 19 | // real data for the GDI object and are shared among all wxWin objects sharing |
| 20 | // the same native GDI object |
| 21 | // ---------------------------------------------------------------------------- |
| 22 | |
| 23 | class WXDLLIMPEXP_CORE wxGDIRefData : public wxObjectRefData |
| 24 | { |
| 25 | public: |
| 26 | // override this in the derived classes to check if this data object is |
| 27 | // really fully initialized |
| 28 | virtual bool IsOk() const { return true; } |
| 29 | }; |
| 30 | |
| 31 | // ---------------------------------------------------------------------------- |
| 32 | // wxGDIObject: base class for bitmaps, pens, brushes, ... |
| 33 | // ---------------------------------------------------------------------------- |
| 34 | |
| 35 | class WXDLLIMPEXP_CORE wxGDIObject : public wxObject |
| 36 | { |
| 37 | public: |
| 38 | // checks if the object can be used |
| 39 | virtual bool IsOk() const |
| 40 | { |
| 41 | // the cast here is safe because the derived classes always create |
| 42 | // wxGDIRefData objects |
| 43 | return m_refData && static_cast<wxGDIRefData *>(m_refData)->IsOk(); |
| 44 | } |
| 45 | |
| 46 | // don't use in the new code, use IsOk() instead |
| 47 | bool IsNull() const { return m_refData == NULL; } |
| 48 | |
| 49 | // older version, for backwards compatibility only (but not deprecated |
| 50 | // because it's still widely used) |
| 51 | bool Ok() const { return IsOk(); } |
| 52 | |
| 53 | #if defined(__WXMSW__) || defined(__WXPM__) || defined(__WXPALMOS__) |
| 54 | // Creates the resource |
| 55 | virtual bool RealizeResource() { return false; } |
| 56 | |
| 57 | // Frees the resource |
| 58 | virtual bool FreeResource(bool WXUNUSED(force) = false) { return false; } |
| 59 | |
| 60 | virtual bool IsFree() const { return false; } |
| 61 | |
| 62 | // Returns handle. |
| 63 | virtual WXHANDLE GetResourceHandle() const { return 0; } |
| 64 | #endif // defined(__WXMSW__) || defined(__WXPM__) |
| 65 | |
| 66 | protected: |
| 67 | // replace base class functions using wxObjectRefData with our own which |
| 68 | // use wxGDIRefData to ensure that we always work with data objects of the |
| 69 | // correct type (i.e. derived from wxGDIRefData) |
| 70 | virtual wxObjectRefData *CreateRefData() const |
| 71 | { |
| 72 | return CreateGDIRefData(); |
| 73 | } |
| 74 | |
| 75 | virtual wxObjectRefData *CloneRefData(const wxObjectRefData *data) const |
| 76 | { |
| 77 | return CloneGDIRefData(static_cast<const wxGDIRefData *>(data)); |
| 78 | } |
| 79 | |
| 80 | virtual wxGDIRefData *CreateGDIRefData() const = 0; |
| 81 | virtual wxGDIRefData *CloneGDIRefData(const wxGDIRefData *data) const = 0; |
| 82 | |
| 83 | DECLARE_DYNAMIC_CLASS(wxGDIObject) |
| 84 | }; |
| 85 | |
| 86 | #endif // _WX_GDIOBJ_H_BASE_ |