]> git.saurik.com Git - wxWidgets.git/blobdiff - src/gtk/toplevel.cpp
More comments about non-native GTH widgets.
[wxWidgets.git] / src / gtk / toplevel.cpp
index d8472ece1d8743876fe31ad0683a1e9b9844bb48..68efed2a0841b4bfe2264bf238a824fe4ce5f307 100644 (file)
@@ -7,6 +7,9 @@
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 
+// For compilers that support precompilation, includes "wx.h".
+#include "wx/wxprec.h"
+
 // ============================================================================
 // declarations
 // ============================================================================
 // headers
 // ----------------------------------------------------------------------------
 
-// For compilers that support precompilation, includes "wx.h".
-#include "wx/wxprec.h"
-
 #ifdef __VMS
 #define XIconifyWindow XICONIFYWINDOW
 #endif
 
-#include "wx/defs.h"
-
 #include "wx/toplevel.h"
-#include "wx/log.h"
-#include "wx/dialog.h"
-#include "wx/control.h"
-#include "wx/app.h"
-#include "wx/dcclient.h"
+
+#ifndef WX_PRECOMP
+    #include "wx/frame.h"
+    #include "wx/icon.h"
+    #include "wx/log.h"
+    #include "wx/app.h"
+#endif
+
 #include "wx/gtk/private.h"
-#include "wx/timer.h"
-#include "wx/settings.h"
 #include "wx/evtloop.h"
 
-#include <glib.h>
-#include <gdk/gdk.h>
 #include <gtk/gtk.h>
-#include <gdk/gdkkeysyms.h>
 #include <gdk/gdkx.h>
 
 #include "wx/gtk/win_gtk.h"
 // XA_CARDINAL
 #include <X11/Xatom.h>
 
-// ----------------------------------------------------------------------------
-// idle system
-// ----------------------------------------------------------------------------
-
-extern void wxapp_install_idle_handler();
-extern bool g_isIdle;
-
 // ----------------------------------------------------------------------------
 // data
 // ----------------------------------------------------------------------------
 
-extern wxList           wxPendingDelete;
-
 extern int              g_openDialogs;
 extern wxWindowGTK     *g_delayedFocus;
 
@@ -101,9 +88,9 @@ static void wxgtk_window_set_urgency_hint (GtkWindow *win,
     XFree(wm_hints);
 }
 
-static gint gtk_frame_urgency_timer_callback( wxTopLevelWindowGTK *win )
+static gboolean gtk_frame_urgency_timer_callback( wxTopLevelWindowGTK *win )
 {
-#if defined(__WXGTK20__) && GTK_CHECK_VERSION(2,7,0)
+#if GTK_CHECK_VERSION(2,7,0)
     if(!gtk_check_version(2,7,0))
         gtk_window_set_urgency_hint(GTK_WINDOW( win->m_widget ), FALSE);
     else
@@ -120,12 +107,11 @@ static gint gtk_frame_urgency_timer_callback( wxTopLevelWindowGTK *win )
 //-----------------------------------------------------------------------------
 
 extern "C" {
-static gint gtk_frame_focus_in_callback( GtkWidget *widget,
+static gboolean gtk_frame_focus_in_callback( GtkWidget *widget,
                                          GdkEvent *WXUNUSED(event),
                                          wxTopLevelWindowGTK *win )
 {
-    if (g_isIdle)
-        wxapp_install_idle_handler();
+    // don't need to install idle handler, its done from "event" signal
 
     switch ( g_sendActivateEvent )
     {
@@ -150,10 +136,10 @@ static gint gtk_frame_focus_in_callback( GtkWidget *widget,
     switch( win->m_urgency_hint )
     {
         default:
-            gtk_timeout_remove( win->m_urgency_hint );
+            g_source_remove( win->m_urgency_hint );
             // no break, fallthrough to remove hint too
         case -1:
-#if defined(__WXGTK20__) && GTK_CHECK_VERSION(2,7,0)
+#if GTK_CHECK_VERSION(2,7,0)
             if(!gtk_check_version(2,7,0))
                 gtk_window_set_urgency_hint(GTK_WINDOW( widget ), FALSE);
             else
@@ -182,12 +168,11 @@ static gint gtk_frame_focus_in_callback( GtkWidget *widget,
 //-----------------------------------------------------------------------------
 
 extern "C" {
-static gint gtk_frame_focus_out_callback( GtkWidget *widget,
+static gboolean gtk_frame_focus_out_callback( GtkWidget *widget,
                                           GdkEventFocus *WXUNUSED(gdk_event),
                                           wxTopLevelWindowGTK *win )
 {
-    if (g_isIdle)
-        wxapp_install_idle_handler();
+    // don't need to install idle handler, its done from "event" signal
 
     // if the focus goes out of our app alltogether, OnIdle() will send
     // wxActivateEvent, otherwise gtk_window_focus_in_callback() will reset
@@ -217,13 +202,12 @@ static gint gtk_frame_focus_out_callback( GtkWidget *widget,
 //-----------------------------------------------------------------------------
 
 extern "C" {
-static gint gtk_frame_focus_callback( GtkWidget *widget, GtkDirectionType WXUNUSED(d), wxWindow *WXUNUSED(win) )
+static gboolean gtk_frame_focus_callback( GtkWidget *widget, GtkDirectionType WXUNUSED(d), wxWindow *WXUNUSED(win) )
 {
     if (g_isIdle)
         wxapp_install_idle_handler();
 
     // This disables GTK's tab traversal
-    gtk_signal_emit_stop_by_name( GTK_OBJECT(widget), "focus" );
     return TRUE;
 }
 }
@@ -244,10 +228,10 @@ static void gtk_frame_size_callback( GtkWidget *WXUNUSED(widget), GtkAllocation*
     if ((win->m_width != alloc->width) || (win->m_height != alloc->height))
     {
 /*
-        wxPrintf( "OnSize from " );
+        wxPrintf( wxT("gtk_frame_size_callback from ") );
         if (win->GetClassInfo() && win->GetClassInfo()->GetClassName())
            wxPrintf( win->GetClassInfo()->GetClassName() );
-        wxPrintf( " %d %d %d %d\n", (int)alloc->x,
+        wxPrintf( wxT(" %d %d %d %d\n"), (int)alloc->x,
                                 (int)alloc->y,
                                 (int)alloc->width,
                                 (int)alloc->height );
@@ -265,10 +249,12 @@ static void gtk_frame_size_callback( GtkWidget *WXUNUSED(widget), GtkAllocation*
 //-----------------------------------------------------------------------------
 
 extern "C" {
-static gint gtk_frame_delete_callback( GtkWidget *WXUNUSED(widget), GdkEvent *WXUNUSED(event), wxTopLevelWindowGTK *win )
+static gboolean
+gtk_frame_delete_callback( GtkWidget *WXUNUSED(widget),
+                           GdkEvent *WXUNUSED(event),
+                           wxTopLevelWindowGTK *win )
 {
-    if (g_isIdle)
-        wxapp_install_idle_handler();
+    // don't need to install idle handler, its done from "event" signal
 
     if (win->IsEnabled() &&
         (g_openDialogs == 0 || (win->GetExtraStyle() & wxTOPLEVEL_EX_DIALOG) ||
@@ -285,11 +271,12 @@ static gint gtk_frame_delete_callback( GtkWidget *WXUNUSED(widget), GdkEvent *WX
 //-----------------------------------------------------------------------------
 
 extern "C" {
-static gint
-gtk_frame_configure_callback( GtkWidget *WXUNUSED(widget), GdkEventConfigure *WXUNUSED(event), wxTopLevelWindowGTK *win )
+static gboolean
+gtk_frame_configure_callback( GtkWidget *WXUNUSED(widget),
+                              GdkEventConfigure *WXUNUSED(event),
+                              wxTopLevelWindowGTK *win )
 {
-    if (g_isIdle)
-        wxapp_install_idle_handler();
+    // don't need to install idle handler, its done from "event" signal
 
     if (!win->m_hasVMT || !win->IsShown())
         return FALSE;
@@ -333,7 +320,7 @@ gtk_frame_realized_callback( GtkWidget * WXUNUSED(widget),
 
     // GTK's shrinking/growing policy
     if ((win->m_gdkFunc & GDK_FUNC_RESIZE) == 0)
-        gtk_window_set_policy(GTK_WINDOW(win->m_widget), 0, 0, 1);
+        gtk_window_set_resizable(GTK_WINDOW(win->m_widget), FALSE);
     else
         gtk_window_set_policy(GTK_WINDOW(win->m_widget), 1, 1, 1);
 
@@ -380,7 +367,10 @@ gtk_frame_unmap_callback( GtkWidget * WXUNUSED(widget),
 //-----------------------------------------------------------------------------
 
 extern "C" {
-static int gtk_window_expose_callback( GtkWidget *widget, GdkEventExpose *gdk_event, wxWindow *win )
+static gboolean
+gtk_window_expose_callback( GtkWidget *widget,
+                            GdkEventExpose *gdk_event,
+                            wxWindow *win )
 {
     GtkPizza *pizza = GTK_PIZZA(widget);
 
@@ -396,29 +386,6 @@ static int gtk_window_expose_callback( GtkWidget *widget, GdkEventExpose *gdk_ev
 }
 }
 
-//-----------------------------------------------------------------------------
-// "draw" of m_client
-//-----------------------------------------------------------------------------
-
-#ifndef __WXGTK20__
-
-extern "C" {
-static void gtk_window_draw_callback( GtkWidget *widget, GdkRectangle *rect, wxWindow *win )
-{
-    GtkPizza *pizza = GTK_PIZZA(widget);
-
-    gtk_paint_flat_box (win->m_widget->style,
-                        pizza->bin_window, GTK_STATE_NORMAL,
-                        GTK_SHADOW_NONE,
-                        rect,
-                        win->m_widget,
-                        (char *)"base",
-                        0, 0, -1, -1);
-}
-}
-
-#endif // GTK+ 1.x
-
 // ----------------------------------------------------------------------------
 // wxTopLevelWindowGTK itself
 // ----------------------------------------------------------------------------
@@ -457,9 +424,6 @@ static void wxInsertChildInTopLevelWindow( wxTopLevelWindowGTK* parent, wxWindow
                          child->m_width,
                          child->m_height );
     }
-
-    // resize on OnInternalIdle
-    parent->GtkUpdateSize();
 }
 
 // ----------------------------------------------------------------------------
@@ -517,7 +481,6 @@ bool wxTopLevelWindowGTK::Create( wxWindow *parent,
     {
         if (GetExtraStyle() & wxTOPLEVEL_EX_DIALOG)
         {
-#ifdef __WXGTK20__
             m_widget = gtk_window_new(GTK_WINDOW_TOPLEVEL);
             // Tell WM that this is a dialog window and make it center
             // on parent by default (this is what GtkDialog ctor does):
@@ -525,9 +488,6 @@ bool wxTopLevelWindowGTK::Create( wxWindow *parent,
                                      GDK_WINDOW_TYPE_HINT_DIALOG);
             gtk_window_set_position(GTK_WINDOW(m_widget),
                                     GTK_WIN_POS_CENTER_ON_PARENT);
-#else
-            m_widget = gtk_window_new(GTK_WINDOW_DIALOG);
-#endif
         }
         else
         {
@@ -582,14 +542,16 @@ bool wxTopLevelWindowGTK::Create( wxWindow *parent,
     }
 #endif
 
+#if 0
     if (!name.empty())
-        gtk_window_set_wmclass( GTK_WINDOW(m_widget), wxGTK_CONV( name ), wxGTK_CONV( name ) );
+        gtk_window_set_role( GTK_WINDOW(m_widget), wxGTK_CONV( name ) );
+#endif
 
     gtk_window_set_title( GTK_WINDOW(m_widget), wxGTK_CONV( title ) );
     GTK_WIDGET_UNSET_FLAGS( m_widget, GTK_CAN_FOCUS );
 
-    gtk_signal_connect( GTK_OBJECT(m_widget), "delete_event",
-        GTK_SIGNAL_FUNC(gtk_frame_delete_callback), (gpointer)this );
+    g_signal_connect (m_widget, "delete_event",
+                      G_CALLBACK (gtk_frame_delete_callback), this);
 
     // m_mainWidget holds the toolbar, the menubar and the client area
     m_mainWidget = gtk_pizza_new();
@@ -600,12 +562,8 @@ bool wxTopLevelWindowGTK::Create( wxWindow *parent,
     if (m_miniEdge == 0) // wxMiniFrame has its own version.
     {
        // For m_mainWidget themes
-       gtk_signal_connect( GTK_OBJECT(m_mainWidget), "expose_event",
-                GTK_SIGNAL_FUNC(gtk_window_expose_callback), (gpointer)this );
-#ifndef __WXGTK20__
-       gtk_signal_connect( GTK_OBJECT(m_mainWidget), "draw",
-                GTK_SIGNAL_FUNC(gtk_window_draw_callback), (gpointer)this );
-#endif
+       g_signal_connect (m_mainWidget, "expose_event",
+                         G_CALLBACK (gtk_window_expose_callback), this);
     }
 
     // m_wxwindow only represents the client area without toolbar and menubar
@@ -620,8 +578,8 @@ bool wxTopLevelWindowGTK::Create( wxWindow *parent,
     if (m_parent) m_parent->AddChild( this );
 
     // the user resized the frame by dragging etc.
-    gtk_signal_connect( GTK_OBJECT(m_widget), "size_allocate",
-        GTK_SIGNAL_FUNC(gtk_frame_size_callback), (gpointer)this );
+    g_signal_connect (m_widget, "size_allocate",
+                      G_CALLBACK (gtk_frame_size_callback), this);
 
     PostCreation();
 
@@ -632,36 +590,45 @@ bool wxTopLevelWindowGTK::Create( wxWindow *parent,
 
     //  we cannot set MWM hints and icons before the widget has
     //  been realized, so we do this directly after realization
-    gtk_signal_connect( GTK_OBJECT(m_widget), "realize",
-                        GTK_SIGNAL_FUNC(gtk_frame_realized_callback), (gpointer) this );
+    g_signal_connect (m_widget, "realize",
+                      G_CALLBACK (gtk_frame_realized_callback), this);
 
     // map and unmap for iconized state
-    gtk_signal_connect( GTK_OBJECT(m_widget), "map_event",
-        GTK_SIGNAL_FUNC(gtk_frame_map_callback), (gpointer)this );
-    gtk_signal_connect( GTK_OBJECT(m_widget), "unmap_event",
-        GTK_SIGNAL_FUNC(gtk_frame_unmap_callback), (gpointer)this );
+    g_signal_connect (m_widget, "map_event",
+                      G_CALLBACK (gtk_frame_map_callback), this);
+    g_signal_connect (m_widget, "unmap_event",
+                      G_CALLBACK (gtk_frame_unmap_callback), this);
 
     // the only way to get the window size is to connect to this event
-    gtk_signal_connect( GTK_OBJECT(m_widget), "configure_event",
-        GTK_SIGNAL_FUNC(gtk_frame_configure_callback), (gpointer)this );
+    g_signal_connect (m_widget, "configure_event",
+                      G_CALLBACK (gtk_frame_configure_callback), this);
 
     // disable native tab traversal
-    gtk_signal_connect( GTK_OBJECT(m_widget), "focus",
-        GTK_SIGNAL_FUNC(gtk_frame_focus_callback), (gpointer)this );
+    g_signal_connect (m_widget, "focus",
+                      G_CALLBACK (gtk_frame_focus_callback), this);
 
     // activation
-    gtk_signal_connect( GTK_OBJECT(m_widget), "focus_in_event",
-        GTK_SIGNAL_FUNC(gtk_frame_focus_in_callback), (gpointer)this );
-    gtk_signal_connect( GTK_OBJECT(m_widget), "focus_out_event",
-        GTK_SIGNAL_FUNC(gtk_frame_focus_out_callback), (gpointer)this );
+    g_signal_connect_after (m_widget, "focus_in_event",
+                      G_CALLBACK (gtk_frame_focus_in_callback), this);
+    g_signal_connect_after (m_widget, "focus_out_event",
+                      G_CALLBACK (gtk_frame_focus_out_callback), this);
 
     // decorations
-    if ((m_miniEdge > 0) || (style & wxSIMPLE_BORDER) || (style & wxNO_BORDER))
+    if ((style & wxSIMPLE_BORDER) || (style & wxNO_BORDER))
     {
         m_gdkDecor = 0;
         m_gdkFunc = 0;
     }
     else
+    if (m_miniEdge > 0)
+    {
+        m_gdkDecor = 0;
+        m_gdkFunc = 0;
+        
+        if ((style & wxRESIZE_BORDER) != 0)
+           m_gdkFunc |= GDK_FUNC_RESIZE;
+    }
+    else
     {
         m_gdkDecor = (long) GDK_DECOR_BORDER;
         m_gdkFunc = (long) GDK_FUNC_MOVE;
@@ -704,7 +671,7 @@ wxTopLevelWindowGTK::~wxTopLevelWindowGTK()
 {
     if (m_grabbed)
     {
-        wxASSERT_MSG( false, _T("Window still grabbed"));
+        wxFAIL_MSG(_T("Window still grabbed"));
         RemoveGrab();
     }
 
@@ -823,6 +790,9 @@ bool wxTopLevelWindowGTK::Show( bool show )
 {
     wxASSERT_MSG( (m_widget != NULL), wxT("invalid frame") );
 
+    if (show == IsShown())
+        return true;
+
     if (show && !m_sizeSet)
     {
         /* by calling GtkOnSize here, we don't have to call
@@ -833,19 +803,18 @@ bool wxTopLevelWindowGTK::Show( bool show )
         GtkOnSize( m_x, m_y, m_width, m_height );
     }
 
-    if (show)
-        gtk_widget_set_uposition( m_widget, m_x, m_y );
+    // This seems no longer to be needed and the call
+    // itself is deprecated.
+    //
+    //if (show)
+    //    gtk_widget_set_uposition( m_widget, m_x, m_y );
 
     return wxWindow::Show( show );
 }
 
 void wxTopLevelWindowGTK::Raise()
 {
-#ifdef __WXGTK20__
     gtk_window_present( GTK_WINDOW( m_widget ) );
-#else
-    wxWindow::Raise();
-#endif
 }
 
 void wxTopLevelWindowGTK::DoMoveWindow(int WXUNUSED(x), int WXUNUSED(y), int WXUNUSED(width), int WXUNUSED(height) )
@@ -1149,7 +1118,6 @@ void wxTopLevelWindowGTK::SetIcons( const wxIconBundle &icons )
 
     wxTopLevelWindowBase::SetIcons( icons );
 
-#ifdef __WXGTK20__
     GList *list = NULL;
     size_t max = icons.m_icons.GetCount();
 
@@ -1162,25 +1130,6 @@ void wxTopLevelWindowGTK::SetIcons( const wxIconBundle &icons )
     }
     gtk_window_set_icon_list(GTK_WINDOW(m_widget), list);
     g_list_free(list);
-
-#else // !__WXGTK20__
-    GdkWindow* window = m_widget->window;
-    if (!window)
-        return;
-
-    wxIcon icon = icons.GetIcon(-1);
-    if (icon.Ok())
-    {
-        wxMask *mask = icon.GetMask();
-        GdkBitmap *bm = (GdkBitmap *) NULL;
-        if (mask) bm = mask->GetBitmap();
-
-        gdk_window_set_icon( m_widget->window, (GdkWindow *) NULL, icon.GetPixmap(), bm );
-    }
-
-    wxSetIconsX11( (WXDisplay*)GDK_WINDOW_XDISPLAY( window ),
-                   (WXWindow)GDK_WINDOW_XWINDOW( window ), icons );
-#endif // !__WXGTK20__
 }
 
 // ----------------------------------------------------------------------------
@@ -1189,61 +1138,32 @@ void wxTopLevelWindowGTK::SetIcons( const wxIconBundle &icons )
 
 void wxTopLevelWindowGTK::Maximize(bool maximize)
 {
-#ifdef __WXGTK20__
     if (maximize)
         gtk_window_maximize( GTK_WINDOW( m_widget ) );
     else
         gtk_window_unmaximize( GTK_WINDOW( m_widget ) );
-#else
-    wxFAIL_MSG( _T("not implemented") );
-#endif
 }
 
 bool wxTopLevelWindowGTK::IsMaximized() const
 {
-#ifdef __WXGTK20__
     if(!m_widget->window)
         return false;
 
     return gdk_window_get_state(m_widget->window) & GDK_WINDOW_STATE_MAXIMIZED;
-#else
-  //    wxFAIL_MSG( _T("not implemented") );
-
-    // This is an approximation
-    return false;
-#endif
 }
 
 void wxTopLevelWindowGTK::Restore()
 {
-#ifdef __WXGTK20__
     // "Present" seems similar enough to "restore"
     gtk_window_present( GTK_WINDOW( m_widget ) );
-#else
-    wxFAIL_MSG( _T("not implemented") );
-#endif
 }
 
 void wxTopLevelWindowGTK::Iconize( bool iconize )
 {
-#ifdef __WXGTK20__
     if (iconize)
         gtk_window_iconify( GTK_WINDOW( m_widget ) );
     else
         gtk_window_deiconify( GTK_WINDOW( m_widget ) );
-#else
-   if (iconize)
-   {
-       GdkWindow *window = m_widget->window;
-
-       // you should do it later, for example from OnCreate() handler
-       wxCHECK_RET( window, _T("frame not created yet - can't iconize") );
-
-       XIconifyWindow( GDK_WINDOW_XDISPLAY( window ),
-                       GDK_WINDOW_XWINDOW( window ),
-                       DefaultScreen( GDK_DISPLAY() ) );
-   }
-#endif
 }
 
 bool wxTopLevelWindowGTK::IsIconized() const
@@ -1292,14 +1212,7 @@ static bool do_shape_combine_region(GdkWindow* window, const wxRegion& region)
         }
         else
         {
-#ifdef __WXGTK20__
             gdk_window_shape_combine_region(window, region.GetRegion(), 0, 0);
-#else
-            wxBitmap bmp = region.ConvertToBitmap();
-            bmp.SetMask(new wxMask(bmp, *wxBLACK));
-            GdkBitmap* mask = bmp.GetMask()->GetBitmap();
-            gdk_window_shape_combine_mask(window, mask, 0, 0);
-#endif
             return true;
         }
     }
@@ -1338,7 +1251,7 @@ void wxTopLevelWindowGTK::RequestUserAttention(int flags)
     ::wxYieldIfNeeded();
 
     if(m_urgency_hint >= 0)
-        gtk_timeout_remove(m_urgency_hint);
+        g_source_remove(m_urgency_hint);
 
     m_urgency_hint = -2;
 
@@ -1348,13 +1261,13 @@ void wxTopLevelWindowGTK::RequestUserAttention(int flags)
 
         if (flags & wxUSER_ATTENTION_INFO)
         {
-            m_urgency_hint = gtk_timeout_add(5000, (GtkFunction)gtk_frame_urgency_timer_callback, this);
+            m_urgency_hint = g_timeout_add(5000, (GSourceFunc)gtk_frame_urgency_timer_callback, this);
         } else {
             m_urgency_hint = -1;
         }
     }
 
-#if defined(__WXGTK20__) && GTK_CHECK_VERSION(2,7,0)
+#if GTK_CHECK_VERSION(2,7,0)
     if(!gtk_check_version(2,7,0))
         gtk_window_set_urgency_hint(GTK_WINDOW( m_widget ), new_hint_value);
     else
@@ -1364,8 +1277,10 @@ void wxTopLevelWindowGTK::RequestUserAttention(int flags)
 
 void wxTopLevelWindowGTK::SetWindowStyleFlag( long style )
 {
+#if defined(__WXGTK24__) || GTK_CHECK_VERSION(2,2,0)
     // Store which styles were changed
     long styleChanges = style ^ m_windowStyle;
+#endif
 
     // Process wxWindow styles. This also updates the internal variable
     // Therefore m_windowStyle bits carry now the _new_ style values
@@ -1378,5 +1293,79 @@ void wxTopLevelWindowGTK::SetWindowStyleFlag( long style )
 #ifdef __WXGTK24__
     if ( (styleChanges & wxSTAY_ON_TOP) && !gtk_check_version(2,4,0) )
         gtk_window_set_keep_above(GTK_WINDOW(m_widget), m_windowStyle & wxSTAY_ON_TOP);
+#endif // GTK+ 2.4
+#if GTK_CHECK_VERSION(2,2,0)
+    if ( (styleChanges & wxFRAME_NO_TASKBAR) && !gtk_check_version(2,2,0) )
+    {
+        gtk_window_set_skip_taskbar_hint(GTK_WINDOW(m_widget), m_windowStyle & wxFRAME_NO_TASKBAR);
+    }
+#endif // GTK+ 2.2
+}
+
+#include <X11/Xlib.h>
+
+/* Get the X Window between child and the root window.
+   This should usually be the WM managed XID */
+static Window wxGetTopmostWindowX11(Display *dpy, Window child)
+{
+    Window root, parent;
+    Window* children;
+    unsigned int nchildren;
+
+    XQueryTree(dpy, child, &root, &parent, &children, &nchildren);
+    XFree(children);
+
+    while (parent != root) {
+        child = parent;
+        XQueryTree(dpy, child, &root, &parent, &children, &nchildren);
+        XFree(children);
+    }
+
+    return child;
+}
+
+bool wxTopLevelWindowGTK::SetTransparent(wxByte alpha)
+{
+    if (!m_widget || !m_widget->window)
+        return false;
+
+    Display* dpy = GDK_WINDOW_XDISPLAY (m_widget->window);
+    // We need to get the X Window that has the root window as the immediate parent
+    // and m_widget->window as a child. This should be the X Window that the WM manages and
+    // from which the opacity property is checked from.
+    Window win = wxGetTopmostWindowX11(dpy, GDK_WINDOW_XID (m_widget->window));
+
+    unsigned int opacity = alpha * 0x1010101;
+
+    // Using pure Xlib to not have a GTK version check mess due to gtk2.0 not having GdkDisplay
+    if (alpha == 0xff)
+        XDeleteProperty(dpy, win, XInternAtom(dpy, "_NET_WM_WINDOW_OPACITY", False));
+    else
+        XChangeProperty(dpy, win, XInternAtom(dpy, "_NET_WM_WINDOW_OPACITY", False),
+                        XA_CARDINAL, 32, PropModeReplace,
+                        (unsigned char *) &opacity, 1L);
+    XSync(dpy, False);
+    return true;
+}
+
+bool wxTopLevelWindowGTK::CanSetTransparent()
+{
+#if GTK_CHECK_VERSION(2,10,0)
+    if (!gtk_check_version(2,10,0))
+    {
+        if (gtk_widget_is_composited (m_widget))
+            return true;
+    }
+    else
+#endif // In case of lower versions than gtk+-2.10.0 we could look for _NET_WM_CM_Sn ourselves
+    {
+        return false;
+    }
+
+#if 0 // Don't be optimistic here for the sake of wxAUI
+    int opcode, event, error;
+    // Check for the existence of a RGBA visual instead?
+    return XQueryExtension(gdk_x11_get_default_xdisplay (),
+                           "Composite", &opcode, &event, &error);
 #endif
 }