src/gtk/win_gtk.cpp

///////////////////////////////////////////////////////////////////////////////
// Name:        src/gtk/win_gtk.cpp
// Purpose:     native GTK+ widget for wxWindow
// Author:      Paul Cornett
// Copyright:   (c) 2007 Paul Cornett
// Licence:     wxWindows licence
///////////////////////////////////////////////////////////////////////////////

#include "wx/wxprec.h"

#include "wx/defs.h"

#include <gtk/gtk.h>
#include "wx/gtk/private/win_gtk.h"

#include "wx/gtk/private.h"
#include "wx/gtk/private/gtk2-compat.h"

/*
wxPizza is a custom GTK+ widget derived from GtkFixed.  A custom widget
is needed to adapt GTK+ to wxWidgets needs in 3 areas: scrolling, window
borders, and RTL.

For scrolling, the "set_scroll_adjustments" signal is implemented
to make wxPizza appear scrollable to GTK+, allowing it to be put in a
GtkScrolledWindow.  Child widget positions are adjusted for the scrolling
position in size_allocate.

For borders, space is reserved in realize and size_allocate.  The border is
drawn on wxPizza's parent GdkWindow.

For RTL, child widget positions are mirrored in size_allocate.
*/

struct wxPizzaChild
{
    GtkWidget* widget;
    int x, y, width, height;
};

static GtkWidgetClass* parent_class;

#ifdef __WXGTK3__
enum {
    PROP_0,
    PROP_HADJUSTMENT,
    PROP_VADJUSTMENT,
    PROP_HSCROLL_POLICY,
    PROP_VSCROLL_POLICY
};
#endif

extern "C" {

struct wxPizzaClass
{
    GtkFixedClass parent;
#ifndef __WXGTK3__
    void (*set_scroll_adjustments)(GtkWidget*, GtkAdjustment*, GtkAdjustment*);
#endif
};

static void pizza_size_allocate(GtkWidget* widget, GtkAllocation* alloc)
{
    wxPizza* pizza = WX_PIZZA(widget);
    GtkBorder border;
    pizza->get_border(border);
    int w = alloc->width - border.left - border.right;
    if (w < 0) w = 0;

    if (gtk_widget_get_realized(widget))
    {
        int h = alloc->height - border.top - border.bottom;
        if (h < 0) h = 0;
        const int x = alloc->x + border.left;
        const int y = alloc->y + border.top;

        GdkWindow* window = gtk_widget_get_window(widget);
        int old_x, old_y;
        gdk_window_get_position(window, &old_x, &old_y);

        if (x != old_x || y != old_y ||
            w != gdk_window_get_width(window) || h != gdk_window_get_height(window))
        {
            gdk_window_move_resize(window, x, y, w, h);

            if (border.left + border.right + border.top + border.bottom)
            {
                // old and new border areas need to be invalidated,
                // otherwise they will not be erased/redrawn properly
                GtkAllocation old_alloc;
                gtk_widget_get_allocation(widget, &old_alloc);
                GdkWindow* parent = gtk_widget_get_parent_window(widget);
                gdk_window_invalidate_rect(parent, &old_alloc, false);
                gdk_window_invalidate_rect(parent, alloc, false);
            }
        }
    }

    gtk_widget_set_allocation(widget, alloc);

    // adjust child positions
    for (const GList* p = pizza->m_children; p; p = p->next)
    {
        const wxPizzaChild* child = static_cast<wxPizzaChild*>(p->data);
        if (gtk_widget_get_visible(child->widget))
        {
            GtkAllocation child_alloc;
            // note that child positions do not take border into
            // account, they need to be relative to widget->window,
            // which has already been adjusted
            child_alloc.x = child->x - pizza->m_scroll_x;
            child_alloc.y = child->y - pizza->m_scroll_y;
            child_alloc.width  = child->width;
            child_alloc.height = child->height;
            if (gtk_widget_get_direction(widget) == GTK_TEXT_DIR_RTL)
                child_alloc.x = w - child_alloc.x - child_alloc.width;
            gtk_widget_size_allocate(child->widget, &child_alloc);
        }
    }
}

static void pizza_realize(GtkWidget* widget)
{
    parent_class->realize(widget);

    wxPizza* pizza = WX_PIZZA(widget);
    if (pizza->m_windowStyle & wxPizza::BORDER_STYLES)
    {
        GtkBorder border;
        pizza->get_border(border);
        GtkAllocation a;
        gtk_widget_get_allocation(widget, &a);
        int x = a.x + border.left;
        int y = a.y + border.top;
        int w = a.width - border.left - border.right;
        int h = a.height - border.top - border.bottom;
        if (w < 0) w = 0;
        if (h < 0) h = 0;
        gdk_window_move_resize(gtk_widget_get_window(widget), x, y, w, h);
    }
}

static void pizza_show(GtkWidget* widget)
{
    GtkWidget* parent = gtk_widget_get_parent(widget);
    if (parent && (WX_PIZZA(widget)->m_windowStyle & wxPizza::BORDER_STYLES))
    {
        // invalidate whole allocation so borders will be drawn properly
        GtkAllocation a;
        gtk_widget_get_allocation(widget, &a);
        gtk_widget_queue_draw_area(parent, a.x, a.y, a.width, a.height);
    }

    parent_class->show(widget);
}

static void pizza_hide(GtkWidget* widget)
{
    GtkWidget* parent = gtk_widget_get_parent(widget);
    if (parent && (WX_PIZZA(widget)->m_windowStyle & wxPizza::BORDER_STYLES))
    {
        // invalidate whole allocation so borders will be erased properly
        GtkAllocation a;
        gtk_widget_get_allocation(widget, &a);
        gtk_widget_queue_draw_area(parent, a.x, a.y, a.width, a.height);
    }

    parent_class->hide(widget);
}

static void pizza_add(GtkContainer* container, GtkWidget* widget)
{
    WX_PIZZA(container)->put(widget, 0, 0, 1, 1);
}

static void pizza_remove(GtkContainer* container, GtkWidget* widget)
{
    GTK_CONTAINER_CLASS(parent_class)->remove(container, widget);

    wxPizza* pizza = WX_PIZZA(container);
    for (GList* p = pizza->m_children; p; p = p->next)
    {
        wxPizzaChild* child = static_cast<wxPizzaChild*>(p->data);
        if (child->widget == widget)
        {
            pizza->m_children = g_list_delete_link(pizza->m_children, p);
            delete child;
            break;
        }
    }
}

#ifdef __WXGTK3__
static void pizza_get_preferred_width(GtkWidget* widget, int* minimum, int* natural)
{
    *minimum = 0;
    gtk_widget_get_size_request(widget, natural, NULL);
    if (*natural < 0)
        *natural = 0;
}

static void pizza_get_preferred_height(GtkWidget* widget, int* minimum, int* natural)
{
    *minimum = 0;
    gtk_widget_get_size_request(widget, NULL, natural);
    if (*natural < 0)
        *natural = 0;
}

// Needed to implement GtkScrollable interface, but we don't care about the
// properties. wxWindowGTK handles the adjustments and scroll policy.
static void pizza_get_property(GObject*, guint, GValue*, GParamSpec*)
{
}

static void pizza_set_property(GObject*, guint, const GValue*, GParamSpec*)
{
}
#else
// not used, but needs to exist so gtk_widget_set_scroll_adjustments will work
static void pizza_set_scroll_adjustments(GtkWidget*, GtkAdjustment*, GtkAdjustment*)
{
}

// Marshaller needed for set_scroll_adjustments signal,
// generated with GLib-2.4.6 glib-genmarshal
#define g_marshal_value_peek_object(v)   g_value_get_object (v)
static void
g_cclosure_user_marshal_VOID__OBJECT_OBJECT (GClosure     *closure,
                                             GValue       * /*return_value*/,
                                             guint         n_param_values,
                                             const GValue *param_values,
                                             gpointer      /*invocation_hint*/,
                                             gpointer      marshal_data)
{
  typedef void (*GMarshalFunc_VOID__OBJECT_OBJECT) (gpointer     data1,
                                                    gpointer     arg_1,
                                                    gpointer     arg_2,
                                                    gpointer     data2);
  register GMarshalFunc_VOID__OBJECT_OBJECT callback;
  register GCClosure *cc = (GCClosure*) closure;
  register gpointer data1, data2;

  g_return_if_fail (n_param_values == 3);

  if (G_CCLOSURE_SWAP_DATA (closure))
    {
      data1 = closure->data;
      data2 = g_value_peek_pointer (param_values + 0);
    }
  else
    {
      data1 = g_value_peek_pointer (param_values + 0);
      data2 = closure->data;
    }
  callback = (GMarshalFunc_VOID__OBJECT_OBJECT) (marshal_data ? marshal_data : cc->callback);

  callback (data1,
            g_marshal_value_peek_object (param_values + 1),
            g_marshal_value_peek_object (param_values + 2),
            data2);
}
#endif

static void class_init(void* g_class, void*)
{
    GtkWidgetClass* widget_class = (GtkWidgetClass*)g_class;
    widget_class->size_allocate = pizza_size_allocate;
    widget_class->realize = pizza_realize;
    widget_class->show = pizza_show;
    widget_class->hide = pizza_hide;
    GtkContainerClass* container_class = (GtkContainerClass*)g_class;
    container_class->add = pizza_add;
    container_class->remove = pizza_remove;

#ifdef __WXGTK3__
    widget_class->get_preferred_width = pizza_get_preferred_width;
    widget_class->get_preferred_height = pizza_get_preferred_height;
    GObjectClass *gobject_class = G_OBJECT_CLASS(g_class);
    gobject_class->set_property = pizza_set_property;
    gobject_class->get_property = pizza_get_property;
    g_object_class_override_property(gobject_class, PROP_HADJUSTMENT, "hadjustment");
    g_object_class_override_property(gobject_class, PROP_VADJUSTMENT, "vadjustment");
    g_object_class_override_property(gobject_class, PROP_HSCROLL_POLICY, "hscroll-policy");
    g_object_class_override_property(gobject_class, PROP_VSCROLL_POLICY, "vscroll-policy");
#else
    wxPizzaClass* klass = static_cast<wxPizzaClass*>(g_class);
    // needed to make widget appear scrollable to GTK+
    klass->set_scroll_adjustments = pizza_set_scroll_adjustments;
    widget_class->set_scroll_adjustments_signal =
        g_signal_new(
            "set_scroll_adjustments",
            G_TYPE_FROM_CLASS(g_class),
            G_SIGNAL_RUN_LAST,
            G_STRUCT_OFFSET(wxPizzaClass, set_scroll_adjustments),
            NULL, NULL,
            g_cclosure_user_marshal_VOID__OBJECT_OBJECT,
            G_TYPE_NONE, 2, GTK_TYPE_ADJUSTMENT, GTK_TYPE_ADJUSTMENT);
#endif
    parent_class = GTK_WIDGET_CLASS(g_type_class_peek_parent(g_class));
}

} // extern "C"

GType wxPizza::type()
{
    static GType type;
    if (type == 0)
    {
        const GTypeInfo info = {
            sizeof(wxPizzaClass),
            NULL, NULL,
            class_init,
            NULL, NULL,
            sizeof(wxPizza), 0,
            NULL, NULL
        };
        type = g_type_register_static(
            GTK_TYPE_FIXED, "wxPizza", &info, GTypeFlags(0));
#ifdef __WXGTK3__
        const GInterfaceInfo interface_info = { NULL, NULL, NULL };
        g_type_add_interface_static(type, GTK_TYPE_SCROLLABLE, &interface_info);
#endif
    }
    return type;
}

GtkWidget* wxPizza::New(long windowStyle)
{
    GtkWidget* widget = GTK_WIDGET(g_object_new(type(), NULL));
    wxPizza* pizza = WX_PIZZA(widget);
    pizza->m_children = NULL;
    pizza->m_scroll_x = 0;
    pizza->m_scroll_y = 0;
    pizza->m_windowStyle = windowStyle;
#ifdef __WXGTK3__
    gtk_widget_set_has_window(widget, true);
#else
    gtk_fixed_set_has_window(GTK_FIXED(widget), true);
#endif
    gtk_widget_add_events(widget,
        GDK_EXPOSURE_MASK |
        GDK_SCROLL_MASK |
        GDK_POINTER_MOTION_MASK |
        GDK_POINTER_MOTION_HINT_MASK |
        GDK_BUTTON_MOTION_MASK |
        GDK_BUTTON1_MOTION_MASK |
        GDK_BUTTON2_MOTION_MASK |
        GDK_BUTTON3_MOTION_MASK |
        GDK_BUTTON_PRESS_MASK |
        GDK_BUTTON_RELEASE_MASK |
        GDK_KEY_PRESS_MASK |
        GDK_KEY_RELEASE_MASK |
        GDK_ENTER_NOTIFY_MASK |
        GDK_LEAVE_NOTIFY_MASK |
        GDK_FOCUS_CHANGE_MASK);
    return widget;
}

void wxPizza::move(GtkWidget* widget, int x, int y, int width, int height)
{
    for (const GList* p = m_children; p; p = p->next)
    {
        wxPizzaChild* child = static_cast<wxPizzaChild*>(p->data);
        if (child->widget == widget)
        {
            child->x = x;
            child->y = y;
            child->width = width;
            child->height = height;
            // normally a queue-resize would be needed here, but we know
            // wxWindowGTK::DoMoveWindow() will take care of it
            break;
        }
    }
}

void wxPizza::put(GtkWidget* widget, int x, int y, int width, int height)
{
    // Re-parenting a TLW under a child window is possible at wx level but
    // using a TLW as child at GTK+ level results in problems, so don't do it.
#if GTK_CHECK_VERSION(2,19,3)
    if (!gtk_widget_is_toplevel(GTK_WIDGET(widget)))
#else
    if (!GTK_WIDGET_TOPLEVEL(GTK_WIDGET(widget)))
#endif
        gtk_fixed_put(GTK_FIXED(this), widget, 0, 0);

    wxPizzaChild* child = new wxPizzaChild;
    child->widget = widget;
    child->x = x;
    child->y = y;
    child->width = width;
    child->height = height;
    m_children = g_list_append(m_children, child);
}

struct AdjustData {
    GdkWindow* window;
    int dx, dy;
};

// Adjust allocations for all widgets using the GdkWindow which was just scrolled
extern "C" {
static void scroll_adjust(GtkWidget* widget, void* data)
{
    const AdjustData* p = static_cast<AdjustData*>(data);
    GtkAllocation a;
    gtk_widget_get_allocation(widget, &a);
    a.x += p->dx;
    a.y += p->dy;
    gtk_widget_set_allocation(widget, &a);

    if (gtk_widget_get_window(widget) == p->window)
    {
        // GtkFrame requires a queue_resize, otherwise parts of
        // the frame newly exposed by the scroll are not drawn.
        // To be safe, do it for all widgets.
        gtk_widget_queue_resize_no_redraw(widget);
        if (GTK_IS_CONTAINER(widget))
            gtk_container_forall(GTK_CONTAINER(widget), scroll_adjust, data);
    }
}
}

void wxPizza::scroll(int dx, int dy)
{
    GtkWidget* widget = GTK_WIDGET(this);
    if (gtk_widget_get_direction(widget) == GTK_TEXT_DIR_RTL)
        dx = -dx;
    m_scroll_x -= dx;
    m_scroll_y -= dy;
    GdkWindow* window = gtk_widget_get_window(widget);
    if (window)
    {
        gdk_window_scroll(window, dx, dy);
        // Adjust child allocations. Doing a queue_resize on the children is not
        // enough, sometimes they redraw in the wrong place during fast scrolling.
        AdjustData data = { window, dx, dy };
        gtk_container_forall(GTK_CONTAINER(widget), scroll_adjust, &data);
    }
}

void wxPizza::get_border(GtkBorder& border)
{
#ifndef __WXUNIVERSAL__
    if (m_windowStyle & wxBORDER_SIMPLE)
        border.left = border.right = border.top = border.bottom = 1;
    else if (m_windowStyle & (wxBORDER_RAISED | wxBORDER_SUNKEN | wxBORDER_THEME))
    {
#ifdef __WXGTK3__
        GtkStyleContext* sc;
        if (m_windowStyle & (wxHSCROLL | wxVSCROLL))
            sc = gtk_widget_get_style_context(wxGTKPrivate::GetTreeWidget());
        else
            sc = gtk_widget_get_style_context(wxGTKPrivate::GetEntryWidget());

        gtk_style_context_get_border(sc, GTK_STATE_FLAG_NORMAL, &border);
#else // !__WXGTK3__
        GtkStyle* style;
        if (m_windowStyle & (wxHSCROLL | wxVSCROLL))
            style = gtk_widget_get_style(wxGTKPrivate::GetTreeWidget());
        else
            style = gtk_widget_get_style(wxGTKPrivate::GetEntryWidget());

        border.left = border.right = style->xthickness;
        border.top = border.bottom = style->ythickness;
#endif // !__WXGTK3__
    }
    else
#endif // !__WXUNIVERSAL__
    {
        border.left = border.right = border.top = border.bottom = 0;
    }
}
Commit	Line	Data
	1	///////////////////////////////////////////////////////////////////////////////
	2	// Name: src/gtk/win_gtk.cpp
	3	// Purpose: native GTK+ widget for wxWindow
	4	// Author: Paul Cornett
	5	// Copyright: (c) 2007 Paul Cornett
	6	// Licence: wxWindows licence
	7	///////////////////////////////////////////////////////////////////////////////
	8
	9	#include "wx/wxprec.h"
	10
	11	#include "wx/defs.h"
	12
	13	#include <gtk/gtk.h>
	14	#include "wx/gtk/private/win_gtk.h"
	15
	16	#include "wx/gtk/private.h"
	17	#include "wx/gtk/private/gtk2-compat.h"
	18
	19	/*
	20	wxPizza is a custom GTK+ widget derived from GtkFixed. A custom widget
	21	is needed to adapt GTK+ to wxWidgets needs in 3 areas: scrolling, window
	22	borders, and RTL.
	23
	24	For scrolling, the "set_scroll_adjustments" signal is implemented
	25	to make wxPizza appear scrollable to GTK+, allowing it to be put in a
	26	GtkScrolledWindow. Child widget positions are adjusted for the scrolling
	27	position in size_allocate.
	28
	29	For borders, space is reserved in realize and size_allocate. The border is
	30	drawn on wxPizza's parent GdkWindow.
	31
	32	For RTL, child widget positions are mirrored in size_allocate.
	33	*/
	34
	35	struct wxPizzaChild
	36	{
	37	GtkWidget* widget;
	38	int x, y, width, height;
	39	};
	40
	41	static GtkWidgetClass* parent_class;
	42
	43	#ifdef __WXGTK3__
	44	enum {
	45	PROP_0,
	46	PROP_HADJUSTMENT,
	47	PROP_VADJUSTMENT,
	48	PROP_HSCROLL_POLICY,
	49	PROP_VSCROLL_POLICY
	50	};
	51	#endif
	52
	53	extern "C" {
	54
	55	struct wxPizzaClass
	56	{
	57	GtkFixedClass parent;
	58	#ifndef __WXGTK3__
	59	void (set_scroll_adjustments)(GtkWidget, GtkAdjustment, GtkAdjustment);
	60	#endif
	61	};
	62
	63	static void pizza_size_allocate(GtkWidget* widget, GtkAllocation* alloc)
	64	{
	65	wxPizza* pizza = WX_PIZZA(widget);
	66	GtkBorder border;
	67	pizza->get_border(border);
	68	int w = alloc->width - border.left - border.right;
	69	if (w < 0) w = 0;
	70
	71	if (gtk_widget_get_realized(widget))
	72	{
	73	int h = alloc->height - border.top - border.bottom;
	74	if (h < 0) h = 0;
	75	const int x = alloc->x + border.left;
	76	const int y = alloc->y + border.top;
	77
	78	GdkWindow* window = gtk_widget_get_window(widget);
	79	int old_x, old_y;
	80	gdk_window_get_position(window, &old_x, &old_y);
	81
	82	if (x != old_x \|\| y != old_y \|\|
	83	w != gdk_window_get_width(window) \|\| h != gdk_window_get_height(window))
	84	{
	85	gdk_window_move_resize(window, x, y, w, h);
	86
	87	if (border.left + border.right + border.top + border.bottom)
	88	{
	89	// old and new border areas need to be invalidated,
	90	// otherwise they will not be erased/redrawn properly
	91	GtkAllocation old_alloc;
	92	gtk_widget_get_allocation(widget, &old_alloc);
	93	GdkWindow* parent = gtk_widget_get_parent_window(widget);
	94	gdk_window_invalidate_rect(parent, &old_alloc, false);
	95	gdk_window_invalidate_rect(parent, alloc, false);
	96	}
	97	}
	98	}
	99
	100	gtk_widget_set_allocation(widget, alloc);
	101
	102	// adjust child positions
	103	for (const GList* p = pizza->m_children; p; p = p->next)
	104	{
	105	const wxPizzaChild* child = static_cast<wxPizzaChild*>(p->data);
	106	if (gtk_widget_get_visible(child->widget))
	107	{
	108	GtkAllocation child_alloc;
	109	// note that child positions do not take border into
	110	// account, they need to be relative to widget->window,
	111	// which has already been adjusted
	112	child_alloc.x = child->x - pizza->m_scroll_x;
	113	child_alloc.y = child->y - pizza->m_scroll_y;
	114	child_alloc.width = child->width;
	115	child_alloc.height = child->height;
	116	if (gtk_widget_get_direction(widget) == GTK_TEXT_DIR_RTL)
	117	child_alloc.x = w - child_alloc.x - child_alloc.width;
	118	gtk_widget_size_allocate(child->widget, &child_alloc);
	119	}
	120	}
	121	}
	122
	123	static void pizza_realize(GtkWidget* widget)
	124	{
	125	parent_class->realize(widget);
	126
	127	wxPizza* pizza = WX_PIZZA(widget);
	128	if (pizza->m_windowStyle & wxPizza::BORDER_STYLES)
	129	{
	130	GtkBorder border;
	131	pizza->get_border(border);
	132	GtkAllocation a;
	133	gtk_widget_get_allocation(widget, &a);
	134	int x = a.x + border.left;
	135	int y = a.y + border.top;
	136	int w = a.width - border.left - border.right;
	137	int h = a.height - border.top - border.bottom;
	138	if (w < 0) w = 0;
	139	if (h < 0) h = 0;
	140	gdk_window_move_resize(gtk_widget_get_window(widget), x, y, w, h);
	141	}
	142	}
	143
	144	static void pizza_show(GtkWidget* widget)
	145	{
	146	GtkWidget* parent = gtk_widget_get_parent(widget);
	147	if (parent && (WX_PIZZA(widget)->m_windowStyle & wxPizza::BORDER_STYLES))
	148	{
	149	// invalidate whole allocation so borders will be drawn properly
	150	GtkAllocation a;
	151	gtk_widget_get_allocation(widget, &a);
	152	gtk_widget_queue_draw_area(parent, a.x, a.y, a.width, a.height);
	153	}
	154
	155	parent_class->show(widget);
	156	}
	157
	158	static void pizza_hide(GtkWidget* widget)
	159	{
	160	GtkWidget* parent = gtk_widget_get_parent(widget);
	161	if (parent && (WX_PIZZA(widget)->m_windowStyle & wxPizza::BORDER_STYLES))
	162	{
	163	// invalidate whole allocation so borders will be erased properly
	164	GtkAllocation a;
	165	gtk_widget_get_allocation(widget, &a);
	166	gtk_widget_queue_draw_area(parent, a.x, a.y, a.width, a.height);
	167	}
	168
	169	parent_class->hide(widget);
	170	}
	171
	172	static void pizza_add(GtkContainer* container, GtkWidget* widget)
	173	{
	174	WX_PIZZA(container)->put(widget, 0, 0, 1, 1);
	175	}
	176
	177	static void pizza_remove(GtkContainer* container, GtkWidget* widget)
	178	{
	179	GTK_CONTAINER_CLASS(parent_class)->remove(container, widget);
	180
	181	wxPizza* pizza = WX_PIZZA(container);
	182	for (GList* p = pizza->m_children; p; p = p->next)
	183	{
	184	wxPizzaChild* child = static_cast<wxPizzaChild*>(p->data);
	185	if (child->widget == widget)
	186	{
	187	pizza->m_children = g_list_delete_link(pizza->m_children, p);
	188	delete child;
	189	break;
	190	}
	191	}
	192	}
	193
	194	#ifdef __WXGTK3__
	195	static void pizza_get_preferred_width(GtkWidget* widget, int* minimum, int* natural)
	196	{
	197	*minimum = 0;
	198	gtk_widget_get_size_request(widget, natural, NULL);
	199	if (*natural < 0)
	200	*natural = 0;
	201	}
	202
	203	static void pizza_get_preferred_height(GtkWidget* widget, int* minimum, int* natural)
	204	{
	205	*minimum = 0;
	206	gtk_widget_get_size_request(widget, NULL, natural);
	207	if (*natural < 0)
	208	*natural = 0;
	209	}
	210
	211	// Needed to implement GtkScrollable interface, but we don't care about the
	212	// properties. wxWindowGTK handles the adjustments and scroll policy.
	213	static void pizza_get_property(GObject, guint, GValue, GParamSpec*)
	214	{
	215	}
	216
	217	static void pizza_set_property(GObject, guint, const GValue, GParamSpec*)
	218	{
	219	}
	220	#else
	221	// not used, but needs to exist so gtk_widget_set_scroll_adjustments will work
	222	static void pizza_set_scroll_adjustments(GtkWidget, GtkAdjustment, GtkAdjustment*)
	223	{
	224	}
	225
	226	// Marshaller needed for set_scroll_adjustments signal,
	227	// generated with GLib-2.4.6 glib-genmarshal
	228	#define g_marshal_value_peek_object(v) g_value_get_object (v)
	229	static void
	230	g_cclosure_user_marshal_VOID__OBJECT_OBJECT (GClosure *closure,
	231	GValue * /return_value/,
	232	guint n_param_values,
	233	const GValue *param_values,
	234	gpointer /invocation_hint/,
	235	gpointer marshal_data)
	236	{
	237	typedef void (*GMarshalFunc_VOID__OBJECT_OBJECT) (gpointer data1,
	238	gpointer arg_1,
	239	gpointer arg_2,
	240	gpointer data2);
	241	register GMarshalFunc_VOID__OBJECT_OBJECT callback;
	242	register GCClosure cc = (GCClosure) closure;
	243	register gpointer data1, data2;
	244
	245	g_return_if_fail (n_param_values == 3);
	246
	247	if (G_CCLOSURE_SWAP_DATA (closure))
	248	{
	249	data1 = closure->data;
	250	data2 = g_value_peek_pointer (param_values + 0);
	251	}
	252	else
	253	{
	254	data1 = g_value_peek_pointer (param_values + 0);
	255	data2 = closure->data;
	256	}
	257	callback = (GMarshalFunc_VOID__OBJECT_OBJECT) (marshal_data ? marshal_data : cc->callback);
	258
	259	callback (data1,
	260	g_marshal_value_peek_object (param_values + 1),
	261	g_marshal_value_peek_object (param_values + 2),
	262	data2);
	263	}
	264	#endif
	265
	266	static void class_init(void* g_class, void*)
	267	{
	268	GtkWidgetClass* widget_class = (GtkWidgetClass*)g_class;
	269	widget_class->size_allocate = pizza_size_allocate;
	270	widget_class->realize = pizza_realize;
	271	widget_class->show = pizza_show;
	272	widget_class->hide = pizza_hide;
	273	GtkContainerClass* container_class = (GtkContainerClass*)g_class;
	274	container_class->add = pizza_add;
	275	container_class->remove = pizza_remove;
	276
	277	#ifdef __WXGTK3__
	278	widget_class->get_preferred_width = pizza_get_preferred_width;
	279	widget_class->get_preferred_height = pizza_get_preferred_height;
	280	GObjectClass *gobject_class = G_OBJECT_CLASS(g_class);
	281	gobject_class->set_property = pizza_set_property;
	282	gobject_class->get_property = pizza_get_property;
	283	g_object_class_override_property(gobject_class, PROP_HADJUSTMENT, "hadjustment");
	284	g_object_class_override_property(gobject_class, PROP_VADJUSTMENT, "vadjustment");
	285	g_object_class_override_property(gobject_class, PROP_HSCROLL_POLICY, "hscroll-policy");
	286	g_object_class_override_property(gobject_class, PROP_VSCROLL_POLICY, "vscroll-policy");
	287	#else
	288	wxPizzaClass* klass = static_cast<wxPizzaClass*>(g_class);
	289	// needed to make widget appear scrollable to GTK+
	290	klass->set_scroll_adjustments = pizza_set_scroll_adjustments;
	291	widget_class->set_scroll_adjustments_signal =
	292	g_signal_new(
	293	"set_scroll_adjustments",
	294	G_TYPE_FROM_CLASS(g_class),
	295	G_SIGNAL_RUN_LAST,
	296	G_STRUCT_OFFSET(wxPizzaClass, set_scroll_adjustments),
	297	NULL, NULL,
	298	g_cclosure_user_marshal_VOID__OBJECT_OBJECT,
	299	G_TYPE_NONE, 2, GTK_TYPE_ADJUSTMENT, GTK_TYPE_ADJUSTMENT);
	300	#endif
	301	parent_class = GTK_WIDGET_CLASS(g_type_class_peek_parent(g_class));
	302	}
	303
	304	} // extern "C"
	305
	306	GType wxPizza::type()
	307	{
	308	static GType type;
	309	if (type == 0)
	310	{
	311	const GTypeInfo info = {
	312	sizeof(wxPizzaClass),
	313	NULL, NULL,
	314	class_init,
	315	NULL, NULL,
	316	sizeof(wxPizza), 0,
	317	NULL, NULL
	318	};
	319	type = g_type_register_static(
	320	GTK_TYPE_FIXED, "wxPizza", &info, GTypeFlags(0));
	321	#ifdef __WXGTK3__
	322	const GInterfaceInfo interface_info = { NULL, NULL, NULL };
	323	g_type_add_interface_static(type, GTK_TYPE_SCROLLABLE, &interface_info);
	324	#endif
	325	}
	326	return type;
	327	}
	328
	329	GtkWidget* wxPizza::New(long windowStyle)
	330	{
	331	GtkWidget* widget = GTK_WIDGET(g_object_new(type(), NULL));
	332	wxPizza* pizza = WX_PIZZA(widget);
	333	pizza->m_children = NULL;
	334	pizza->m_scroll_x = 0;
	335	pizza->m_scroll_y = 0;
	336	pizza->m_windowStyle = windowStyle;
	337	#ifdef __WXGTK3__
	338	gtk_widget_set_has_window(widget, true);
	339	#else
	340	gtk_fixed_set_has_window(GTK_FIXED(widget), true);
	341	#endif
	342	gtk_widget_add_events(widget,
	343	GDK_EXPOSURE_MASK \|
	344	GDK_SCROLL_MASK \|
	345	GDK_POINTER_MOTION_MASK \|
	346	GDK_POINTER_MOTION_HINT_MASK \|
	347	GDK_BUTTON_MOTION_MASK \|
	348	GDK_BUTTON1_MOTION_MASK \|
	349	GDK_BUTTON2_MOTION_MASK \|
	350	GDK_BUTTON3_MOTION_MASK \|
	351	GDK_BUTTON_PRESS_MASK \|
	352	GDK_BUTTON_RELEASE_MASK \|
	353	GDK_KEY_PRESS_MASK \|
	354	GDK_KEY_RELEASE_MASK \|
	355	GDK_ENTER_NOTIFY_MASK \|
	356	GDK_LEAVE_NOTIFY_MASK \|
	357	GDK_FOCUS_CHANGE_MASK);
	358	return widget;
	359	}
	360
	361	void wxPizza::move(GtkWidget* widget, int x, int y, int width, int height)
	362	{
	363	for (const GList* p = m_children; p; p = p->next)
	364	{
	365	wxPizzaChild* child = static_cast<wxPizzaChild*>(p->data);
	366	if (child->widget == widget)
	367	{
	368	child->x = x;
	369	child->y = y;
	370	child->width = width;
	371	child->height = height;
	372	// normally a queue-resize would be needed here, but we know
	373	// wxWindowGTK::DoMoveWindow() will take care of it
	374	break;
	375	}
	376	}
	377	}
	378
	379	void wxPizza::put(GtkWidget* widget, int x, int y, int width, int height)
	380	{
	381	// Re-parenting a TLW under a child window is possible at wx level but
	382	// using a TLW as child at GTK+ level results in problems, so don't do it.
	383	#if GTK_CHECK_VERSION(2,19,3)
	384	if (!gtk_widget_is_toplevel(GTK_WIDGET(widget)))
	385	#else
	386	if (!GTK_WIDGET_TOPLEVEL(GTK_WIDGET(widget)))
	387	#endif
	388	gtk_fixed_put(GTK_FIXED(this), widget, 0, 0);
	389
	390	wxPizzaChild* child = new wxPizzaChild;
	391	child->widget = widget;
	392	child->x = x;
	393	child->y = y;
	394	child->width = width;
	395	child->height = height;
	396	m_children = g_list_append(m_children, child);
	397	}
	398
	399	struct AdjustData {
	400	GdkWindow* window;
	401	int dx, dy;
	402	};
	403
	404	// Adjust allocations for all widgets using the GdkWindow which was just scrolled
	405	extern "C" {
	406	static void scroll_adjust(GtkWidget* widget, void* data)
	407	{
	408	const AdjustData* p = static_cast<AdjustData*>(data);
	409	GtkAllocation a;
	410	gtk_widget_get_allocation(widget, &a);
	411	a.x += p->dx;
	412	a.y += p->dy;
	413	gtk_widget_set_allocation(widget, &a);
	414
	415	if (gtk_widget_get_window(widget) == p->window)
	416	{
	417	// GtkFrame requires a queue_resize, otherwise parts of
	418	// the frame newly exposed by the scroll are not drawn.
	419	// To be safe, do it for all widgets.
	420	gtk_widget_queue_resize_no_redraw(widget);
	421	if (GTK_IS_CONTAINER(widget))
	422	gtk_container_forall(GTK_CONTAINER(widget), scroll_adjust, data);
	423	}
	424	}
	425	}
	426
	427	void wxPizza::scroll(int dx, int dy)
	428	{
	429	GtkWidget* widget = GTK_WIDGET(this);
	430	if (gtk_widget_get_direction(widget) == GTK_TEXT_DIR_RTL)
	431	dx = -dx;
	432	m_scroll_x -= dx;
	433	m_scroll_y -= dy;
	434	GdkWindow* window = gtk_widget_get_window(widget);
	435	if (window)
	436	{
	437	gdk_window_scroll(window, dx, dy);
	438	// Adjust child allocations. Doing a queue_resize on the children is not
	439	// enough, sometimes they redraw in the wrong place during fast scrolling.
	440	AdjustData data = { window, dx, dy };
	441	gtk_container_forall(GTK_CONTAINER(widget), scroll_adjust, &data);
	442	}
	443	}
	444
	445	void wxPizza::get_border(GtkBorder& border)
	446	{
	447	#ifndef __WXUNIVERSAL__
	448	if (m_windowStyle & wxBORDER_SIMPLE)
	449	border.left = border.right = border.top = border.bottom = 1;
	450	else if (m_windowStyle & (wxBORDER_RAISED \| wxBORDER_SUNKEN \| wxBORDER_THEME))
	451	{
	452	#ifdef __WXGTK3__
	453	GtkStyleContext* sc;
	454	if (m_windowStyle & (wxHSCROLL \| wxVSCROLL))
	455	sc = gtk_widget_get_style_context(wxGTKPrivate::GetTreeWidget());
	456	else
	457	sc = gtk_widget_get_style_context(wxGTKPrivate::GetEntryWidget());
	458
	459	gtk_style_context_get_border(sc, GTK_STATE_FLAG_NORMAL, &border);
	460	#else // !__WXGTK3__
	461	GtkStyle* style;
	462	if (m_windowStyle & (wxHSCROLL \| wxVSCROLL))
	463	style = gtk_widget_get_style(wxGTKPrivate::GetTreeWidget());
	464	else
	465	style = gtk_widget_get_style(wxGTKPrivate::GetEntryWidget());
	466
	467	border.left = border.right = style->xthickness;
	468	border.top = border.bottom = style->ythickness;
	469	#endif // !__WXGTK3__
	470	}
	471	else
	472	#endif // !__WXUNIVERSAL__
	473	{
	474	border.left = border.right = border.top = border.bottom = 0;
	475	}
	476	}