create stock GDI objects on demand; use const with GDI objects appropriately (patch 1445355)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@38765 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/os2/gdiobj.cpp

@@ -12,7 +12,48 @@
 #include "wx/wxprec.h"
 
 #include "wx/gdiobj.h"
+#include "wx/gdicmn.h"
 
 IMPLEMENT_DYNAMIC_CLASS(wxGDIObject, wxObject)
 
-// TODO: Nothing to do, unless you want to.
+class wxStockGDIPM: public wxStockGDI
+{
+public:
+    wxStockGDIPM();
+
+    virtual const wxFont* GetFont(Item item);
+
+private:
+    typedef wxStockGDI super;
+};
+
+static wxStockGDIPM gs_wxStockGDIPM_instance;
+
+wxStockGDIPM::wxStockGDIPM()
+{
+    // Override default instance
+    ms_instance = this;
+}
+
+const wxFont* wxStockGDIPM::GetFont(Item item)
+{
+    wxFont* font = wx_static_cast(wxFont*, ms_stockObject[item]);
+    if (font == NULL)
+    {
+        const int fontSize = 12;
+        switch (item)
+        {
+        case FONT_NORMAL:
+            font = new wxFont(fontSize, wxMODERN, wxNORMAL, wxBOLD);
+            break;
+        case FONT_SMALL:
+            font = new wxFont(fontSize - 4, wxSWISS, wxNORMAL, wxNORMAL);
+            break;
+        default:
+            font = wx_const_cast(wxFont*, super::GetFont(item));
+            break;
+        }
+        ms_stockObject[item] = font;
+    }
+    return font;
+}