]> git.saurik.com Git - wxWidgets.git/blobdiff - src/gtk/settings.cpp
document CreateConfig() (extended patch 1739374)
[wxWidgets.git] / src / gtk / settings.cpp
index a525955a9a16a9d22c6bc3a3f8bc54e45b97b1ba..ff3abce216d17fdc908c98702627494929042d1a 100644 (file)
@@ -1,30 +1,34 @@
 /////////////////////////////////////////////////////////////////////////////
-// Name:        gtk/settings.cpp
+// Name:        src/gtk/settings.cpp
 // Purpose:
 // Author:      Robert Roebling
+// Modified by: Mart Raudsepp (GetMetric)
 // Id:          $Id$
 // Copyright:   (c) 1998 Robert Roebling
-// Licence:     wxWidgets licence
+// Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 
-
-#if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
-#pragma implementation "settings.h"
-#endif
-
 // For compilers that support precompilation, includes "wx.h".
 #include "wx/wxprec.h"
 
 #include "wx/settings.h"
-#include "wx/debug.h"
-#include "wx/cmndata.h"
+
+#ifndef WX_PRECOMP
+    #include "wx/cmndata.h"
+    #include "wx/toplevel.h"
+#endif
+
 #include "wx/fontutil.h"
 
-#include <gdk/gdk.h>
-#include <gdk/gdkprivate.h>
+#include <gtk/gtkversion.h>
+#if GTK_CHECK_VERSION(2, 9, 0)
+    // gtk_object_sink
+    #undef GTK_DISABLE_DEPRECATED
+#endif
 #include <gtk/gtk.h>
+#include <gdk/gdkx.h>
 
-#define SHIFT (8*(sizeof(short int)-sizeof(char)))
+#include <X11/Xatom.h>
 
 // ----------------------------------------------------------------------------
 // wxSystemObjects
@@ -38,7 +42,10 @@ struct wxSystemObjects
              m_colHighlight,
              m_colHighlightText,
              m_colListBox,
-             m_colBtnText;
+             m_colBtnText,
+             m_colMenuItemHighlight,
+             m_colTooltip,
+             m_colTooltipText;
 
     wxFont m_fontSystem;
 };
@@ -53,7 +60,8 @@ static wxSystemObjects gs_objects;
 enum wxGtkWidgetType
 {
     wxGTK_BUTTON,
-    wxGTK_LIST
+    wxGTK_LIST,
+    wxGTK_MENUITEM
 };
 
 // the colour we need
@@ -65,8 +73,8 @@ enum wxGtkColourType
 };
 
 // wxSystemSettings::GetColour() helper: get the colours from a GTK+
-// widget style, return true if we did get them, false to use defaults
-static bool GetColourFromGTKWidget(int& red, int& green, int& blue,
+// widget style, return true if we did get them
+static bool GetColourFromGTKWidget(GdkColor& gdkColor,
                                    wxGtkWidgetType type = wxGTK_BUTTON,
                                    GtkStateType state = GTK_STATE_NORMAL,
                                    wxGtkColourType colour = wxGTK_BG)
@@ -83,17 +91,21 @@ static bool GetColourFromGTKWidget(int& red, int& green, int& blue,
             break;
 
         case wxGTK_LIST:
-            widget = gtk_list_new();
+            widget = gtk_tree_view_new_with_model(
+                (GtkTreeModel*)gtk_list_store_new(1, G_TYPE_INT));
+            break;
+
+        case wxGTK_MENUITEM:
+            widget = gtk_menu_item_new();
     }
 
     GtkStyle *def = gtk_rc_get_style( widget );
     if ( !def )
         def = gtk_widget_get_default_style();
 
-    bool ok;
-    if ( def )
+    const bool ok = def != NULL;
+    if (ok)
     {
-        GdkColor *col;
         switch ( colour )
         {
             default:
@@ -101,27 +113,17 @@ static bool GetColourFromGTKWidget(int& red, int& green, int& blue,
                 // fall through
 
             case wxGTK_FG:
-                col = def->fg;
+                gdkColor = def->fg[state];
                 break;
 
             case wxGTK_BG:
-                col = def->bg;
+                gdkColor = def->bg[state];
                 break;
 
             case wxGTK_BASE:
-                col = def->base;
+                gdkColor = def->base[state];
                 break;
         }
-
-        red = col[state].red;
-        green = col[state].green;
-        blue = col[state].blue;
-
-        ok = TRUE;
-    }
-    else
-    {
-        ok = FALSE;
     }
 
     gtk_widget_destroy( widget );
@@ -129,13 +131,33 @@ static bool GetColourFromGTKWidget(int& red, int& green, int& blue,
     return ok;
 }
 
+static void GetTooltipColors()
+{
+    GtkTooltips* tooltips = gtk_tooltips_new();
+    gtk_tooltips_force_window(tooltips);
+    gtk_widget_ensure_style(tooltips->tip_window);
+    GdkColor c = tooltips->tip_window->style->bg[GTK_STATE_NORMAL];
+    gs_objects.m_colTooltip = wxColor(c);
+    c = tooltips->tip_window->style->fg[GTK_STATE_NORMAL];
+    gs_objects.m_colTooltipText = wxColor(c);
+#if GTK_CHECK_VERSION(2, 9, 0)
+    if (gtk_check_version(2, 9, 0) == NULL)
+        g_object_ref_sink(tooltips);
+    else
+#endif
+    {
+        gtk_object_sink((GtkObject*)tooltips);
+    }
+}
+
 wxColour wxSystemSettingsNative::GetColour( wxSystemColour index )
 {
+    wxColor color;
+    GdkColor gdkColor;
     switch (index)
     {
         case wxSYS_COLOUR_SCROLLBAR:
         case wxSYS_COLOUR_BACKGROUND:
-        case wxSYS_COLOUR_ACTIVECAPTION:
         case wxSYS_COLOUR_INACTIVECAPTION:
         case wxSYS_COLOUR_MENU:
         case wxSYS_COLOUR_WINDOWFRAME:
@@ -146,25 +168,22 @@ wxColour wxSystemSettingsNative::GetColour( wxSystemColour index )
         case wxSYS_COLOUR_3DLIGHT:
             if (!gs_objects.m_colBtnFace.Ok())
             {
-                int red, green, blue;
-                if ( !GetColourFromGTKWidget(red, green, blue) )
-                {
-                    red =
-                    green = 0;
-                    blue = 0x9c40;
-                }
-
-                gs_objects.m_colBtnFace = wxColour( red   >> SHIFT,
-                                                   green >> SHIFT,
-                                                   blue  >> SHIFT );
+                gdkColor.red =
+                gdkColor.green = 0;
+                gdkColor.blue = 0x9c40;
+                GetColourFromGTKWidget(gdkColor);
+                gs_objects.m_colBtnFace = wxColor(gdkColor);
             }
-            return gs_objects.m_colBtnFace;
+            color = gs_objects.m_colBtnFace;
+            break;
 
         case wxSYS_COLOUR_WINDOW:
-            return *wxWHITE;
+            color = *wxWHITE;
+            break;
 
         case wxSYS_COLOUR_3DDKSHADOW:
-            return *wxBLACK;
+            color = *wxBLACK;
+            break;
 
         case wxSYS_COLOUR_GRAYTEXT:
         case wxSYS_COLOUR_BTNSHADOW:
@@ -173,150 +192,161 @@ wxColour wxSystemSettingsNative::GetColour( wxSystemColour index )
             {
                 wxColour faceColour(GetColour(wxSYS_COLOUR_3DFACE));
                 gs_objects.m_colBtnShadow =
-                   wxColour((unsigned char) (faceColour.Red() * 0.666),
-                            (unsigned char) (faceColour.Green() * 0.666),
-                            (unsigned char) (faceColour.Blue() * 0.666));
+                   wxColour((unsigned char) (faceColour.Red() * 2 / 3),
+                            (unsigned char) (faceColour.Green() * 2 / 3),
+                            (unsigned char) (faceColour.Blue() * 2 / 3));
             }
-
-            return gs_objects.m_colBtnShadow;
+            color = gs_objects.m_colBtnShadow;
+            break;
 
         case wxSYS_COLOUR_3DHIGHLIGHT:
         //case wxSYS_COLOUR_BTNHIGHLIGHT:
-            return * wxWHITE;
+            color = *wxWHITE;
+            break;
 
         case wxSYS_COLOUR_HIGHLIGHT:
             if (!gs_objects.m_colHighlight.Ok())
             {
-                int red, green, blue;
-                if ( !GetColourFromGTKWidget(red, green, blue,
-                                             wxGTK_BUTTON,
-                                             GTK_STATE_SELECTED) )
-                {
-                    red =
-                    green = 0;
-                    blue = 0x9c40;
-                }
-
-                gs_objects.m_colHighlight = wxColour( red   >> SHIFT,
-                                                        green >> SHIFT,
-                                                        blue  >> SHIFT );
+                gdkColor.red =
+                gdkColor.green = 0;
+                gdkColor.blue = 0x9c40;
+                GetColourFromGTKWidget(
+                    gdkColor, wxGTK_BUTTON, GTK_STATE_SELECTED);
+                gs_objects.m_colHighlight = wxColour(gdkColor);
             }
-            return gs_objects.m_colHighlight;
+            color = gs_objects.m_colHighlight;
+            break;
 
         case wxSYS_COLOUR_LISTBOX:
             if (!gs_objects.m_colListBox.Ok())
             {
-                int red, green, blue;
-                if ( GetColourFromGTKWidget(red, green, blue,
+                if ( GetColourFromGTKWidget(gdkColor,
                                             wxGTK_LIST,
                                             GTK_STATE_NORMAL,
                                             wxGTK_BASE) )
                 {
-                    gs_objects.m_colListBox = wxColour( red   >> SHIFT,
-                                                          green >> SHIFT,
-                                                          blue  >> SHIFT );
+                    gs_objects.m_colListBox = wxColour(gdkColor);
                 }
                 else
                 {
-                    gs_objects.m_colListBox = wxColour(*wxWHITE);
+                    gs_objects.m_colListBox = *wxWHITE;
                 }
             }
-            return gs_objects.m_colListBox;
+            color = gs_objects.m_colListBox;
+            break;
 
         case wxSYS_COLOUR_MENUTEXT:
         case wxSYS_COLOUR_WINDOWTEXT:
         case wxSYS_COLOUR_CAPTIONTEXT:
         case wxSYS_COLOUR_INACTIVECAPTIONTEXT:
         case wxSYS_COLOUR_BTNTEXT:
-        case wxSYS_COLOUR_INFOTEXT:
             if (!gs_objects.m_colBtnText.Ok())
             {
-                int red, green, blue;
-                if ( !GetColourFromGTKWidget(red, green, blue,
-                                             wxGTK_BUTTON,
-                                             GTK_STATE_NORMAL,
-                                             wxGTK_FG) )
-                {
-                    red =
-                    green =
-                    blue = 0;
-                }
-
-                gs_objects.m_colBtnText = wxColour( red   >> SHIFT,
-                                                      green >> SHIFT,
-                                                      blue  >> SHIFT );
+                gdkColor.red =
+                gdkColor.green =
+                gdkColor.blue = 0;
+                GetColourFromGTKWidget(
+                    gdkColor, wxGTK_BUTTON, GTK_STATE_NORMAL, wxGTK_FG);
+                gs_objects.m_colBtnText = wxColour(gdkColor);
             }
-            return gs_objects.m_colBtnText;
+            color = gs_objects.m_colBtnText;
+            break;
 
-            // this (as well as wxSYS_COLOUR_INFOTEXT above) is used for
-            // tooltip windows - Robert, please change this code to use the
-            // real GTK tooltips when/if you can (TODO)
         case wxSYS_COLOUR_INFOBK:
-            return wxColour(255, 255, 225);
+            if (!gs_objects.m_colTooltip.Ok()) {
+                GetTooltipColors();
+            }
+            color = gs_objects.m_colTooltip;
+            break;
+
+        case wxSYS_COLOUR_INFOTEXT:
+            if (!gs_objects.m_colTooltipText.Ok()) {
+                GetTooltipColors();
+            }
+            color = gs_objects.m_colTooltipText;
+            break;
 
         case wxSYS_COLOUR_HIGHLIGHTTEXT:
             if (!gs_objects.m_colHighlightText.Ok())
             {
                 wxColour hclr = GetColour(wxSYS_COLOUR_HIGHLIGHT);
                 if (hclr.Red() > 200 && hclr.Green() > 200 && hclr.Blue() > 200)
-                    gs_objects.m_colHighlightText = wxColour(*wxBLACK);
+                    gs_objects.m_colHighlightText = *wxBLACK;
                 else
-                    gs_objects.m_colHighlightText = wxColour(*wxWHITE);
+                    gs_objects.m_colHighlightText = *wxWHITE;
             }
-            return gs_objects.m_colHighlightText;
+            color = gs_objects.m_colHighlightText;
+            break;
 
         case wxSYS_COLOUR_APPWORKSPACE:
-            return *wxWHITE;    // ?
+            color = *wxWHITE;    // ?
+            break;
+
+        case wxSYS_COLOUR_ACTIVECAPTION:
+        case wxSYS_COLOUR_MENUHILIGHT:
+            if (!gs_objects.m_colMenuItemHighlight.Ok())
+            {
+                gdkColor.red =
+                gdkColor.green =
+                gdkColor.blue = 0;
+                GetColourFromGTKWidget(
+                    gdkColor, wxGTK_MENUITEM, GTK_STATE_SELECTED, wxGTK_BG);
+                gs_objects.m_colMenuItemHighlight = wxColour(gdkColor);
+            }
+            color = gs_objects.m_colMenuItemHighlight;
+            break;
 
         case wxSYS_COLOUR_HOTLIGHT:
         case wxSYS_COLOUR_GRADIENTACTIVECAPTION:
         case wxSYS_COLOUR_GRADIENTINACTIVECAPTION:
-        case wxSYS_COLOUR_MENUHILIGHT:
             // TODO
-            return *wxBLACK;
+            color = *wxBLACK;
+            break;
 
         case wxSYS_COLOUR_MAX:
         default:
             wxFAIL_MSG( _T("unknown system colour index") );
-  }
+            color = *wxWHITE;
+            break;
+    }
 
-  return *wxWHITE;
+    return color;
 }
 
 wxFont wxSystemSettingsNative::GetFont( wxSystemFont index )
 {
+    wxFont font;
     switch (index)
     {
         case wxSYS_OEM_FIXED_FONT:
         case wxSYS_ANSI_FIXED_FONT:
         case wxSYS_SYSTEM_FIXED_FONT:
-        {
-            return *wxNORMAL_FONT;
-        }
+            font = *wxNORMAL_FONT;
+            break;
+
         case wxSYS_ANSI_VAR_FONT:
         case wxSYS_SYSTEM_FONT:
         case wxSYS_DEVICE_DEFAULT_FONT:
         case wxSYS_DEFAULT_GUI_FONT:
-        {
             if (!gs_objects.m_fontSystem.Ok())
             {
-#ifdef __WXGTK20__
                 GtkWidget *widget = gtk_button_new();
                 GtkStyle *def = gtk_rc_get_style( widget );
                 if ( !def || !def->font_desc )
-                    def = gtk_widget_get_default_style();  
+                    def = gtk_widget_get_default_style();
                 if ( def && def->font_desc )
-                {  
-                    wxNativeFontInfo info;  
-                    info.description = def->font_desc;  
-                    gs_objects.m_fontSystem = wxFont(info);  
-                }  
-                else  
-                {  
+                {
+                    wxNativeFontInfo info;
+                    info.description =
+                        pango_font_description_copy(def->font_desc);
+                    gs_objects.m_fontSystem = wxFont(info);
+                }
+                else
+                {
                     GtkSettings *settings = gtk_settings_get_default();
                     gchar *font_name = NULL;
                     g_object_get ( settings,
-                                   "gtk-font-name", 
+                                   "gtk-font-name",
                                    &font_name,
                                    NULL);
                     if (!font_name)
@@ -324,38 +354,250 @@ wxFont wxSystemSettingsNative::GetFont( wxSystemFont index )
                     else
                         gs_objects.m_fontSystem = wxFont(wxString::FromAscii(font_name));
                     g_free (font_name);
-                }  
+                }
                 gtk_widget_destroy( widget );
-#else
-                gs_objects.m_fontSystem = wxFont( 12, wxSWISS, wxNORMAL, wxNORMAL );
-#endif
             }
-            return gs_objects.m_fontSystem;
-        }
+            font = gs_objects.m_fontSystem;
+            break;
 
         default:
-            return wxNullFont;
+            break;
     }
+    return font;
 }
 
-int wxSystemSettingsNative::GetMetric( wxSystemMetric index )
+static bool wxXGetWindowProperty(GdkWindow* window, Atom& type, int& format, gulong& nitems, guchar*& data)
 {
+    bool success = false;
+#if GTK_CHECK_VERSION(2, 2, 0)
+    if (gtk_check_version(2, 2, 0) == NULL)
+    {
+        gulong bytes_after;
+        success = XGetWindowProperty(
+            GDK_DISPLAY_XDISPLAY(gdk_drawable_get_display(window)),
+            GDK_WINDOW_XWINDOW(window),
+            gdk_x11_get_xatom_by_name_for_display(
+                gdk_drawable_get_display(window),
+                "_NET_FRAME_EXTENTS"),
+            0, // left, right, top, bottom, CARDINAL[4]/32
+            G_MAXLONG, // size of long
+            false, // do not delete property
+            XA_CARDINAL, // 32 bit
+            &type, &format, &nitems, &bytes_after, &data
+            ) == Success;
+    }
+#endif
+    return success;
+}
+
+int wxSystemSettingsNative::GetMetric( wxSystemMetric index, wxWindow* win )
+{
+    guchar *data = NULL;
+    Atom type;
+    int format;
+    gulong nitems;
+    GdkWindow *window = NULL;
+    if(win && GTK_WIDGET_REALIZED(win->GetHandle()))
+        window = win->GetHandle()->window;
+
     switch (index)
     {
-        case wxSYS_SCREEN_X:   return gdk_screen_width();
-        case wxSYS_SCREEN_Y:   return gdk_screen_height();
-        case wxSYS_HSCROLL_Y:  return 15;
-        case wxSYS_VSCROLL_X:  return 15;
+        case wxSYS_BORDER_X:
+        case wxSYS_BORDER_Y:
+        case wxSYS_EDGE_X:
+        case wxSYS_EDGE_Y:
+        case wxSYS_FRAMESIZE_X:
+        case wxSYS_FRAMESIZE_Y:
+            // If a window is specified/realized, and it is a toplevel window, we can query from wm.
+            // The returned border thickness is outside the client area in that case.
+            if (window)
+            {
+                wxTopLevelWindow *tlw = wxDynamicCast(win, wxTopLevelWindow);
+                if (!tlw)
+                    return -1; // not a tlw, not sure how to approach
+                else
+                {
+                    // Check if wm supports frame extents - we can't know
+                    // the border widths if it does not.
+#if GTK_CHECK_VERSION(2,2,0)
+                    if (!gtk_check_version(2,2,0))
+                    {
+                        if (!gdk_x11_screen_supports_net_wm_hint(
+                                gdk_drawable_get_screen(window),
+                                gdk_atom_intern("_NET_FRAME_EXTENTS", false) ) )
+                            return -1;
+                    }
+                    else
+#endif
+                    {
+                        if (!gdk_net_wm_supports(gdk_atom_intern("_NET_FRAME_EXTENTS", false)))
+                            return -1;
+                    }
+
+                    // Get the frame extents from the windowmanager.
+                    // In most cases the top extent is the titlebar, so we use the bottom extent
+                    // for the heights.
+                    if (wxXGetWindowProperty(window, type, format, nitems, data))
+                    {
+                        int border_return = -1;
+
+                        if ((type == XA_CARDINAL) && (format == 32) && (nitems >= 4) && (data))
+                        {
+                            switch(index)
+                            {
+                                case wxSYS_BORDER_X:
+                                case wxSYS_EDGE_X:
+                                case wxSYS_FRAMESIZE_X:
+                                    border_return = int(data[1]); // width of right extent
+                                    break;
+                                default:
+                                    border_return = int(data[3]); // height of bottom extent
+                                    break;
+                            }
+                        }
+
+                        if (data)
+                            XFree(data);
+
+                        return border_return;
+                    }
+                }
+            }
+
+            return -1; // no window specified
+
+        case wxSYS_CURSOR_X:
+        case wxSYS_CURSOR_Y:
+#ifdef __WXGTK24__
+            if (!gtk_check_version(2,4,0))
+            {
+                if (window)
+                    return gdk_display_get_default_cursor_size(gdk_drawable_get_display(window));
+                else
+                    return gdk_display_get_default_cursor_size(gdk_display_get_default());
+            }
+            else
+#endif
+                return 16;
+
+        case wxSYS_DCLICK_X:
+        case wxSYS_DCLICK_Y:
+            gint dclick_distance;
+#if GTK_CHECK_VERSION(2,2,0)
+            if (window && !gtk_check_version(2,2,0))
+                g_object_get(gtk_settings_get_for_screen(gdk_drawable_get_screen(window)),
+                                "gtk-double-click-distance", &dclick_distance, NULL);
+            else
+#endif
+                g_object_get(gtk_settings_get_default(),
+                                "gtk-double-click-distance", &dclick_distance, NULL);
+
+            return dclick_distance * 2;
+
+        case wxSYS_DRAG_X:
+        case wxSYS_DRAG_Y:
+            gint drag_threshold;
+#if GTK_CHECK_VERSION(2,2,0)
+            if (window && !gtk_check_version(2,2,0))
+            {
+                g_object_get(
+                        gtk_settings_get_for_screen(gdk_drawable_get_screen(window)),
+                        "gtk-dnd-drag-threshold",
+                        &drag_threshold, NULL);
+            }
+            else
+#endif
+            {
+                g_object_get(gtk_settings_get_default(),
+                             "gtk-dnd-drag-threshold", &drag_threshold, NULL);
+            }
+
+            // The correct thing here would be to double the value
+            // since that is what the API wants. But the values
+            // are much bigger under GNOME than under Windows and
+            // just seem to much in many cases to be useful.
+            // drag_threshold *= 2;
+
+            return drag_threshold;
 
-        // VZ: is there any way to get the cursor size with GDK?
-        case wxSYS_CURSOR_X:   return 16;
-        case wxSYS_CURSOR_Y:   return 16;
         // MBN: ditto for icons
         case wxSYS_ICON_X:     return 32;
         case wxSYS_ICON_Y:     return 32;
-        default:               
-            wxFAIL_MSG( wxT("wxSystemSettings::GetMetric not fully implemented") );
+
+        case wxSYS_SCREEN_X:
+#if GTK_CHECK_VERSION(2,2,0)
+            if (window && !gtk_check_version(2,2,0))
+                return gdk_screen_get_width(gdk_drawable_get_screen(window));
+            else
+#endif
+                return gdk_screen_width();
+
+        case wxSYS_SCREEN_Y:
+#if GTK_CHECK_VERSION(2,2,0)
+            if (window && !gtk_check_version(2,2,0))
+                return gdk_screen_get_height(gdk_drawable_get_screen(window));
+            else
+#endif
+                return gdk_screen_height();
+
+        case wxSYS_HSCROLL_Y:  return 15;
+        case wxSYS_VSCROLL_X:  return 15;
+
+        case wxSYS_CAPTION_Y:
+            if (!window)
+                // No realized window specified, and no implementation for that case yet.
+                return -1;
+
+            // Check if wm supports frame extents - we can't know the caption height if it does not.
+#if GTK_CHECK_VERSION(2,2,0)
+            if (!gtk_check_version(2,2,0))
+            {
+                if (!gdk_x11_screen_supports_net_wm_hint(
+                        gdk_drawable_get_screen(window),
+                        gdk_atom_intern("_NET_FRAME_EXTENTS", false) ) )
+                    return -1;
+            }
+            else
+#endif
+            {
+                if (!gdk_net_wm_supports(gdk_atom_intern("_NET_FRAME_EXTENTS", false)))
+                    return -1;
+            }
+
+            wxASSERT_MSG( wxDynamicCast(win, wxTopLevelWindow),
+                          wxT("Asking for caption height of a non toplevel window") );
+
+            // Get the height of the top windowmanager border.
+            // This is the titlebar in most cases. The titlebar might be elsewhere, and
+            // we could check which is the thickest wm border to decide on which side the
+            // titlebar is, but this might lead to interesting behaviours in used code.
+            // Reconsider when we have a way to report to the user on which side it is.
+            if (wxXGetWindowProperty(window, type, format, nitems, data))
+            {
+                int caption_height = -1;
+
+                if ((type == XA_CARDINAL) && (format == 32) && (nitems >= 3) && (data))
+                {
+                    caption_height = int(data[2]); // top frame extent
+                }
+
+                if (data)
+                    XFree(data);
+
+                return caption_height;
+            }
+
+            // Try a default approach without a window pointer, if possible
+            // ...
+
+            return -1;
+
+        case wxSYS_PENWINDOWS_PRESENT:
+            // No MS Windows for Pen computing extension available in X11 based gtk+.
             return 0;
+
+        default:
+            return -1;   // metric is unknown
     }
 }
 
@@ -363,13 +605,13 @@ bool wxSystemSettingsNative::HasFeature(wxSystemFeature index)
 {
     switch (index)
     {
-        case wxSYS_CAN_ICONIZE_FRAME: 
-            return FALSE; 
-            break;
+        case wxSYS_CAN_ICONIZE_FRAME:
+            return false;
+
         case wxSYS_CAN_DRAW_FRAME_DECORATIONS:
-            return TRUE; 
-            break;
+            return true;
+
         default:
-            return FALSE;
+            return false;
     }
 }