src/gtk/win_gtk.cpp

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

#include "wx/defs.h"
#include "wx/gtk/private/win_gtk.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.  A second same-size GdkWindow is placed behind
widget->window, to allow GDK to use a more efficient scrolling technique.

For borders, space is reserved in realize and size_allocate.
For non-scrolling wxWindows, a second GdkWindow is used for the
border; scrolling wxWindows draw their border on wxPizza's parent
(a GtkScrolledWindow) GdkWindow.  Border widths for sunken and raised
styles are taken from widget->style, so they will match the current theme.

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

static GtkWidgetClass* parent_class;

extern "C" {

struct wxPizzaClass
{
    GtkFixedClass parent;
    void (*set_scroll_adjustments)(GtkWidget*, GtkAdjustment*, GtkAdjustment*);
};

static void size_allocate(GtkWidget* widget, GtkAllocation* alloc)
{
    const bool is_resize =
        widget->allocation.width  != alloc->width ||
        widget->allocation.height != alloc->height;
    const bool is_move =
        widget->allocation.x != alloc->x ||
        widget->allocation.y != alloc->y;

    widget->allocation = *alloc;

    wxPizza* pizza = WX_PIZZA(widget);
    int border_x, border_y;
    pizza->get_border_widths(border_x, border_y);
    int w = alloc->width - 2 * border_x;
    if (w < 0) w = 0;

    if (GTK_WIDGET_REALIZED(widget) && (is_move || is_resize))
    {
        int h = alloc->height - 2 * border_y;
        if (h < 0) h = 0;

        if (pizza->m_is_scrollable)
        {
            // two windows, both same size
            gdk_window_move_resize(pizza->m_backing_window,
                alloc->x + border_x, alloc->y + border_y, w, h);
            if (is_resize)
                gdk_window_resize(widget->window, w, h);
        }
        else if (pizza->m_backing_window)
        {
            // two windows, widget->window is smaller by border widths (need to
            // move widget->window as well as resize because border can change)
            gdk_window_move_resize(pizza->m_backing_window,
                alloc->x, alloc->y, alloc->width, alloc->height);
            gdk_window_move_resize(widget->window, border_x, border_y, w, h);
        }
        else
        {
            // one window
            gdk_window_move_resize(widget->window,
                alloc->x, alloc->y, alloc->width, alloc->height);
        }
        if (is_resize && pizza->m_backing_window)
        {
            // wxWidgets turns off redraw-on-allocate by default,
            // so border area needs to be invalidated
            if (border_x > 1 || border_y > 1)
            {
                if (pizza->m_is_scrollable)
                    ; // invalidate does not seem to be needed in this case
                else
                    gdk_window_invalidate_rect(pizza->m_backing_window, NULL, false);
            }
        }
    }
    // adjust child positions
    for (const GList* list = pizza->m_fixed.children; list; list = list->next)
    {
        const GtkFixedChild* child = static_cast<GtkFixedChild*>(list->data);
        if (GTK_WIDGET_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;
            GtkRequisition req;
            gtk_widget_get_child_requisition(child->widget, &req);
            child_alloc.width  = req.width;
            child_alloc.height = req.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 realize(GtkWidget* widget)
{
    parent_class->realize(widget);

    wxPizza* pizza = WX_PIZZA(widget);
    // second window is created if there is a border, or wxWindow is scrollable
    if (pizza->m_border_style || pizza->m_is_scrollable)
    {
        GdkWindowAttr attr;
        attr.event_mask = pizza->m_is_scrollable ? 0 : GDK_EXPOSURE_MASK;
        attr.x = widget->allocation.x;
        attr.y = widget->allocation.y;
        attr.width = widget->allocation.width;
        attr.height = widget->allocation.height;
        int border_x, border_y;
        pizza->get_border_widths(border_x, border_y);
        int w = widget->allocation.width  - 2 * border_x;
        int h = widget->allocation.height - 2 * border_y;
        if (w < 0) w = 0;
        if (h < 0) h = 0;
        if (pizza->m_is_scrollable)
        {
            attr.x += border_x;
            attr.y += border_y;
            attr.width  = w;
            attr.height = h;
        }
        attr.wclass = GDK_INPUT_OUTPUT;
        attr.visual = gtk_widget_get_visual(widget);
        attr.colormap = gtk_widget_get_colormap(widget);
        attr.window_type = GDK_WINDOW_CHILD;

        pizza->m_backing_window = gdk_window_new(
            gdk_window_get_parent(widget->window),
            &attr,
            GDK_WA_X | GDK_WA_Y | GDK_WA_VISUAL | GDK_WA_COLORMAP);

        gdk_window_set_user_data(pizza->m_backing_window, widget);
        if (pizza->m_is_scrollable)
            gdk_window_reparent(widget->window, pizza->m_backing_window, 0, 0);
        else
            gdk_window_reparent(widget->window, pizza->m_backing_window, border_x, border_y);
        gdk_window_resize(widget->window, w, h);

        // Parts of m_backing_window which are supposed to be obscured may be
        // exposed temporarily while resizing. Setting the backing pixmap to
        // None prevents those areas from being briefly painted black.
        gdk_window_set_back_pixmap(pizza->m_backing_window, NULL, false);
    }
}

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

    wxPizza* pizza = WX_PIZZA(widget);
    if (pizza->m_backing_window)
    {
        gdk_window_set_user_data(pizza->m_backing_window, NULL);
        gdk_window_destroy(pizza->m_backing_window);
        pizza->m_backing_window = NULL;
    }
}

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

    wxPizza* pizza = WX_PIZZA(widget);
    if (pizza->m_backing_window)
        gdk_window_show(pizza->m_backing_window);
}

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

    wxPizza* pizza = WX_PIZZA(widget);
    if (pizza->m_backing_window)
        gdk_window_hide(pizza->m_backing_window);
}

// not used, but needs to exist so gtk_widget_set_scroll_adjustments will work
static void 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);
}

static void class_init(void* g_class, void*)
{
    GtkWidgetClass* widget_class = (GtkWidgetClass*)g_class;
    widget_class->size_allocate = size_allocate;
    widget_class->realize = realize;
    widget_class->unrealize = unrealize;
    widget_class->map = map;
    widget_class->unmap = unmap;
    wxPizzaClass* klass = (wxPizzaClass*)g_class;

    // needed to make widget appear scrollable to GTK+
    klass->set_scroll_adjustments = 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);

    parent_class = GTK_WIDGET_CLASS(g_type_class_peek_parent(g_class));
}

} // extern "C"

GType wxPizza::type()
{
    static GtkType 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));
    }
    return type;
}

GtkWidget* wxPizza::New(long windowStyle)
{
    GtkWidget* widget = GTK_WIDGET(g_object_new(type(), NULL));
    wxPizza* pizza = WX_PIZZA(widget);
    pizza->m_backing_window = NULL;
    pizza->m_scroll_x = 0;
    pizza->m_scroll_y = 0;
    pizza->m_is_scrollable = (windowStyle & (wxHSCROLL | wxVSCROLL)) != 0;
    // mask off border styles not useable with wxPizza
    pizza->m_border_style = int(windowStyle & BORDER_STYLES);
    gtk_fixed_set_has_window(GTK_FIXED(widget), true);
    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;
}

// gtk_fixed_move does not check for a change before issuing a queue_resize,
// we need to avoid that to prevent endless sizing loops, so check first
void wxPizza::move(GtkWidget* widget, int x, int y)
{
    GtkFixed* fixed = &m_fixed;
    for (const GList* list = fixed->children; list; list = list->next)
    {
        const GtkFixedChild* child = static_cast<GtkFixedChild*>(list->data);
        if (child->widget == widget)
        {
            if (child->x != x || child->y != y)
                gtk_fixed_move(fixed, widget, x, y);
            break;
        }
    }
}

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);
    if (widget->window == p->window)
    {
        widget->allocation.x += p->dx;
        widget->allocation.y += p->dy;
        // 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;
    if (widget->window)
    {
        gdk_window_scroll(widget->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 = { widget->window, dx, dy };
        gtk_container_forall(GTK_CONTAINER(widget), scroll_adjust, &data);
    }
}

extern GtkWidget *GetEntryWidget();

void wxPizza::get_border_widths(int& x, int& y)
{
    x = y = 0;
    if (m_border_style & wxBORDER_SIMPLE)
        x = y = 1;
    else if (m_border_style)
    {
        GtkWidget *entry_widget = GetEntryWidget();
        if (entry_widget->style)
        {
            x = entry_widget->style->xthickness;
            y = entry_widget->style->ythickness;
        }
    }
}
Commit	Line	Data
	1	///////////////////////////////////////////////////////////////////////////////
	2	// Name: src/gtk/win_gtk.cpp
	3	// Purpose: native GTK+ widget for wxWindow
	4	// Author: Paul Cornett
	5	// Id: $Id$
	6	// Copyright: (c) 2007 Paul Cornett
	7	// Licence: wxWindows licence
	8	///////////////////////////////////////////////////////////////////////////////
	9
	10	#include "wx/defs.h"
	11	#include "wx/gtk/private/win_gtk.h"
	12
	13	/*
	14	wxPizza is a custom GTK+ widget derived from GtkFixed. A custom widget
	15	is needed to adapt GTK+ to wxWidgets needs in 3 areas: scrolling, window
	16	borders, and RTL.
	17
	18	For scrolling, the "set_scroll_adjustments" signal is implemented
	19	to make wxPizza appear scrollable to GTK+, allowing it to be put in a
	20	GtkScrolledWindow. Child widget positions are adjusted for the scrolling
	21	position in size_allocate. A second same-size GdkWindow is placed behind
	22	widget->window, to allow GDK to use a more efficient scrolling technique.
	23
	24	For borders, space is reserved in realize and size_allocate.
	25	For non-scrolling wxWindows, a second GdkWindow is used for the
	26	border; scrolling wxWindows draw their border on wxPizza's parent
	27	(a GtkScrolledWindow) GdkWindow. Border widths for sunken and raised
	28	styles are taken from widget->style, so they will match the current theme.
	29
	30	For RTL, child widget positions are mirrored in size_allocate.
	31	*/
	32
	33	static GtkWidgetClass* parent_class;
	34
	35	extern "C" {
	36
	37	struct wxPizzaClass
	38	{
	39	GtkFixedClass parent;
	40	void (set_scroll_adjustments)(GtkWidget, GtkAdjustment, GtkAdjustment);
	41	};
	42
	43	static void size_allocate(GtkWidget* widget, GtkAllocation* alloc)
	44	{
	45	const bool is_resize =
	46	widget->allocation.width != alloc->width \|\|
	47	widget->allocation.height != alloc->height;
	48	const bool is_move =
	49	widget->allocation.x != alloc->x \|\|
	50	widget->allocation.y != alloc->y;
	51
	52	widget->allocation = *alloc;
	53
	54	wxPizza* pizza = WX_PIZZA(widget);
	55	int border_x, border_y;
	56	pizza->get_border_widths(border_x, border_y);
	57	int w = alloc->width - 2 * border_x;
	58	if (w < 0) w = 0;
	59
	60	if (GTK_WIDGET_REALIZED(widget) && (is_move \|\| is_resize))
	61	{
	62	int h = alloc->height - 2 * border_y;
	63	if (h < 0) h = 0;
	64
	65	if (pizza->m_is_scrollable)
	66	{
	67	// two windows, both same size
	68	gdk_window_move_resize(pizza->m_backing_window,
	69	alloc->x + border_x, alloc->y + border_y, w, h);
	70	if (is_resize)
	71	gdk_window_resize(widget->window, w, h);
	72	}
	73	else if (pizza->m_backing_window)
	74	{
	75	// two windows, widget->window is smaller by border widths (need to
	76	// move widget->window as well as resize because border can change)
	77	gdk_window_move_resize(pizza->m_backing_window,
	78	alloc->x, alloc->y, alloc->width, alloc->height);
	79	gdk_window_move_resize(widget->window, border_x, border_y, w, h);
	80	}
	81	else
	82	{
	83	// one window
	84	gdk_window_move_resize(widget->window,
	85	alloc->x, alloc->y, alloc->width, alloc->height);
	86	}
	87	if (is_resize && pizza->m_backing_window)
	88	{
	89	// wxWidgets turns off redraw-on-allocate by default,
	90	// so border area needs to be invalidated
	91	if (border_x > 1 \|\| border_y > 1)
	92	{
	93	if (pizza->m_is_scrollable)
	94	; // invalidate does not seem to be needed in this case
	95	else
	96	gdk_window_invalidate_rect(pizza->m_backing_window, NULL, false);
	97	}
	98	}
	99	}
	100	// adjust child positions
	101	for (const GList* list = pizza->m_fixed.children; list; list = list->next)
	102	{
	103	const GtkFixedChild* child = static_cast<GtkFixedChild*>(list->data);
	104	if (GTK_WIDGET_VISIBLE(child->widget))
	105	{
	106	GtkAllocation child_alloc;
	107	// note that child positions do not take border into
	108	// account, they need to be relative to widget->window,
	109	// which has already been adjusted
	110	child_alloc.x = child->x - pizza->m_scroll_x;
	111	child_alloc.y = child->y - pizza->m_scroll_y;
	112	GtkRequisition req;
	113	gtk_widget_get_child_requisition(child->widget, &req);
	114	child_alloc.width = req.width;
	115	child_alloc.height = req.height;
	116	if (gtk_widget_get_direction(widget) == GTK_TEXT_DIR_RTL)
	117	{
	118	child_alloc.x = w - child_alloc.x - child_alloc.width;
	119	}
	120	gtk_widget_size_allocate(child->widget, &child_alloc);
	121	}
	122	}
	123	}
	124
	125	static void realize(GtkWidget* widget)
	126	{
	127	parent_class->realize(widget);
	128
	129	wxPizza* pizza = WX_PIZZA(widget);
	130	// second window is created if there is a border, or wxWindow is scrollable
	131	if (pizza->m_border_style \|\| pizza->m_is_scrollable)
	132	{
	133	GdkWindowAttr attr;
	134	attr.event_mask = pizza->m_is_scrollable ? 0 : GDK_EXPOSURE_MASK;
	135	attr.x = widget->allocation.x;
	136	attr.y = widget->allocation.y;
	137	attr.width = widget->allocation.width;
	138	attr.height = widget->allocation.height;
	139	int border_x, border_y;
	140	pizza->get_border_widths(border_x, border_y);
	141	int w = widget->allocation.width - 2 * border_x;
	142	int h = widget->allocation.height - 2 * border_y;
	143	if (w < 0) w = 0;
	144	if (h < 0) h = 0;
	145	if (pizza->m_is_scrollable)
	146	{
	147	attr.x += border_x;
	148	attr.y += border_y;
	149	attr.width = w;
	150	attr.height = h;
	151	}
	152	attr.wclass = GDK_INPUT_OUTPUT;
	153	attr.visual = gtk_widget_get_visual(widget);
	154	attr.colormap = gtk_widget_get_colormap(widget);
	155	attr.window_type = GDK_WINDOW_CHILD;
	156
	157	pizza->m_backing_window = gdk_window_new(
	158	gdk_window_get_parent(widget->window),
	159	&attr,
	160	GDK_WA_X \| GDK_WA_Y \| GDK_WA_VISUAL \| GDK_WA_COLORMAP);
	161
	162	gdk_window_set_user_data(pizza->m_backing_window, widget);
	163	if (pizza->m_is_scrollable)
	164	gdk_window_reparent(widget->window, pizza->m_backing_window, 0, 0);
	165	else
	166	gdk_window_reparent(widget->window, pizza->m_backing_window, border_x, border_y);
	167	gdk_window_resize(widget->window, w, h);
	168
	169	// Parts of m_backing_window which are supposed to be obscured may be
	170	// exposed temporarily while resizing. Setting the backing pixmap to
	171	// None prevents those areas from being briefly painted black.
	172	gdk_window_set_back_pixmap(pizza->m_backing_window, NULL, false);
	173	}
	174	}
	175
	176	static void unrealize(GtkWidget* widget)
	177	{
	178	parent_class->unrealize(widget);
	179
	180	wxPizza* pizza = WX_PIZZA(widget);
	181	if (pizza->m_backing_window)
	182	{
	183	gdk_window_set_user_data(pizza->m_backing_window, NULL);
	184	gdk_window_destroy(pizza->m_backing_window);
	185	pizza->m_backing_window = NULL;
	186	}
	187	}
	188
	189	static void map(GtkWidget* widget)
	190	{
	191	parent_class->map(widget);
	192
	193	wxPizza* pizza = WX_PIZZA(widget);
	194	if (pizza->m_backing_window)
	195	gdk_window_show(pizza->m_backing_window);
	196	}
	197
	198	static void unmap(GtkWidget* widget)
	199	{
	200	parent_class->unmap(widget);
	201
	202	wxPizza* pizza = WX_PIZZA(widget);
	203	if (pizza->m_backing_window)
	204	gdk_window_hide(pizza->m_backing_window);
	205	}
	206
	207	// not used, but needs to exist so gtk_widget_set_scroll_adjustments will work
	208	static void set_scroll_adjustments(GtkWidget, GtkAdjustment, GtkAdjustment*)
	209	{
	210	}
	211
	212	// Marshaller needed for set_scroll_adjustments signal,
	213	// generated with GLib-2.4.6 glib-genmarshal
	214	#define g_marshal_value_peek_object(v) g_value_get_object (v)
	215	static void
	216	g_cclosure_user_marshal_VOID__OBJECT_OBJECT (GClosure *closure,
	217	GValue * /return_value/,
	218	guint n_param_values,
	219	const GValue *param_values,
	220	gpointer /invocation_hint/,
	221	gpointer marshal_data)
	222	{
	223	typedef void (*GMarshalFunc_VOID__OBJECT_OBJECT) (gpointer data1,
	224	gpointer arg_1,
	225	gpointer arg_2,
	226	gpointer data2);
	227	register GMarshalFunc_VOID__OBJECT_OBJECT callback;
	228	register GCClosure cc = (GCClosure) closure;
	229	register gpointer data1, data2;
	230
	231	g_return_if_fail (n_param_values == 3);
	232
	233	if (G_CCLOSURE_SWAP_DATA (closure))
	234	{
	235	data1 = closure->data;
	236	data2 = g_value_peek_pointer (param_values + 0);
	237	}
	238	else
	239	{
	240	data1 = g_value_peek_pointer (param_values + 0);
	241	data2 = closure->data;
	242	}
	243	callback = (GMarshalFunc_VOID__OBJECT_OBJECT) (marshal_data ? marshal_data : cc->callback);
	244
	245	callback (data1,
	246	g_marshal_value_peek_object (param_values + 1),
	247	g_marshal_value_peek_object (param_values + 2),
	248	data2);
	249	}
	250
	251	static void class_init(void* g_class, void*)
	252	{
	253	GtkWidgetClass* widget_class = (GtkWidgetClass*)g_class;
	254	widget_class->size_allocate = size_allocate;
	255	widget_class->realize = realize;
	256	widget_class->unrealize = unrealize;
	257	widget_class->map = map;
	258	widget_class->unmap = unmap;
	259	wxPizzaClass* klass = (wxPizzaClass*)g_class;
	260
	261	// needed to make widget appear scrollable to GTK+
	262	klass->set_scroll_adjustments = set_scroll_adjustments;
	263	widget_class->set_scroll_adjustments_signal =
	264	g_signal_new(
	265	"set_scroll_adjustments",
	266	G_TYPE_FROM_CLASS(g_class),
	267	G_SIGNAL_RUN_LAST,
	268	G_STRUCT_OFFSET(wxPizzaClass, set_scroll_adjustments),
	269	NULL, NULL,
	270	g_cclosure_user_marshal_VOID__OBJECT_OBJECT,
	271	G_TYPE_NONE, 2, GTK_TYPE_ADJUSTMENT, GTK_TYPE_ADJUSTMENT);
	272
	273	parent_class = GTK_WIDGET_CLASS(g_type_class_peek_parent(g_class));
	274	}
	275
	276	} // extern "C"
	277
	278	GType wxPizza::type()
	279	{
	280	static GtkType type;
	281	if (type == 0)
	282	{
	283	const GTypeInfo info = {
	284	sizeof(wxPizzaClass),
	285	NULL, NULL,
	286	class_init,
	287	NULL, NULL,
	288	sizeof(wxPizza), 0,
	289	NULL, NULL
	290	};
	291	type = g_type_register_static(
	292	GTK_TYPE_FIXED, "wxPizza", &info, GTypeFlags(0));
	293	}
	294	return type;
	295	}
	296
	297	GtkWidget* wxPizza::New(long windowStyle)
	298	{
	299	GtkWidget* widget = GTK_WIDGET(g_object_new(type(), NULL));
	300	wxPizza* pizza = WX_PIZZA(widget);
	301	pizza->m_backing_window = NULL;
	302	pizza->m_scroll_x = 0;
	303	pizza->m_scroll_y = 0;
	304	pizza->m_is_scrollable = (windowStyle & (wxHSCROLL \| wxVSCROLL)) != 0;
	305	// mask off border styles not useable with wxPizza
	306	pizza->m_border_style = int(windowStyle & BORDER_STYLES);
	307	gtk_fixed_set_has_window(GTK_FIXED(widget), true);
	308	gtk_widget_add_events(widget,
	309	GDK_EXPOSURE_MASK \|
	310	GDK_SCROLL_MASK \|
	311	GDK_POINTER_MOTION_MASK \|
	312	GDK_POINTER_MOTION_HINT_MASK \|
	313	GDK_BUTTON_MOTION_MASK \|
	314	GDK_BUTTON1_MOTION_MASK \|
	315	GDK_BUTTON2_MOTION_MASK \|
	316	GDK_BUTTON3_MOTION_MASK \|
	317	GDK_BUTTON_PRESS_MASK \|
	318	GDK_BUTTON_RELEASE_MASK \|
	319	GDK_KEY_PRESS_MASK \|
	320	GDK_KEY_RELEASE_MASK \|
	321	GDK_ENTER_NOTIFY_MASK \|
	322	GDK_LEAVE_NOTIFY_MASK \|
	323	GDK_FOCUS_CHANGE_MASK);
	324	return widget;
	325	}
	326
	327	// gtk_fixed_move does not check for a change before issuing a queue_resize,
	328	// we need to avoid that to prevent endless sizing loops, so check first
	329	void wxPizza::move(GtkWidget* widget, int x, int y)
	330	{
	331	GtkFixed* fixed = &m_fixed;
	332	for (const GList* list = fixed->children; list; list = list->next)
	333	{
	334	const GtkFixedChild* child = static_cast<GtkFixedChild*>(list->data);
	335	if (child->widget == widget)
	336	{
	337	if (child->x != x \|\| child->y != y)
	338	gtk_fixed_move(fixed, widget, x, y);
	339	break;
	340	}
	341	}
	342	}
	343
	344	struct AdjustData {
	345	GdkWindow* window;
	346	int dx, dy;
	347	};
	348
	349	// Adjust allocations for all widgets using the GdkWindow which was just scrolled
	350	extern "C" {
	351	static void scroll_adjust(GtkWidget* widget, void* data)
	352	{
	353	const AdjustData* p = static_cast<AdjustData*>(data);
	354	if (widget->window == p->window)
	355	{
	356	widget->allocation.x += p->dx;
	357	widget->allocation.y += p->dy;
	358	// GtkFrame requires a queue_resize, otherwise parts of
	359	// the frame newly exposed by the scroll are not drawn.
	360	// To be safe, do it for all widgets.
	361	gtk_widget_queue_resize_no_redraw(widget);
	362	if (GTK_IS_CONTAINER(widget))
	363	gtk_container_forall(GTK_CONTAINER(widget), scroll_adjust, data);
	364	}
	365	}
	366	}
	367
	368	void wxPizza::scroll(int dx, int dy)
	369	{
	370	GtkWidget* widget = GTK_WIDGET(this);
	371	if (gtk_widget_get_direction(widget) == GTK_TEXT_DIR_RTL)
	372	dx = -dx;
	373	m_scroll_x -= dx;
	374	m_scroll_y -= dy;
	375	if (widget->window)
	376	{
	377	gdk_window_scroll(widget->window, dx, dy);
	378	// Adjust child allocations. Doing a queue_resize on the children is not
	379	// enough, sometimes they redraw in the wrong place during fast scrolling.
	380	AdjustData data = { widget->window, dx, dy };
	381	gtk_container_forall(GTK_CONTAINER(widget), scroll_adjust, &data);
	382	}
	383	}
	384
	385	extern GtkWidget *GetEntryWidget();
	386
	387	void wxPizza::get_border_widths(int& x, int& y)
	388	{
	389	x = y = 0;
	390	if (m_border_style & wxBORDER_SIMPLE)
	391	x = y = 1;
	392	else if (m_border_style)
	393	{
	394	GtkWidget *entry_widget = GetEntryWidget();
	395	if (entry_widget->style)
	396	{
	397	x = entry_widget->style->xthickness;
	398	y = entry_widget->style->ythickness;
	399	}
	400	}
	401	}