gtk/demos/gtk-demo/dnd.c
Florian "sp1rit"​ 4b619930f2
demo: Fix drag and drop demo critical
Right now, child is NULL when starting a drag in the main area and
moving the pointer onto the colors, there releasing it.
To avoid gtk_widget_get_ancestor thowing a critical, early exit if child
is NULL.
2024-11-02 19:25:01 +01:00

845 lines
24 KiB
C

/* Drag-and-Drop
* #Keywords: dnd, menu, popover, gesture
*
* This demo shows dragging colors and widgets.
* The items in this demo can be moved, recolored
* and rotated.
*
* The demo also has an example for creating a
* menu-like popover without using a menu model.
*/
#include <gtk/gtk.h>
G_DECLARE_FINAL_TYPE (CanvasItem, canvas_item, CANVAS, ITEM, GtkWidget)
struct _CanvasItem {
GtkWidget parent;
GtkWidget *fixed;
GtkWidget *label;
double r;
double angle;
double delta;
GtkWidget *editor;
GtkStyleProvider *provider;
char *css_class;
};
struct _CanvasItemClass {
GtkWidgetClass parent_class;
};
G_DEFINE_TYPE (CanvasItem, canvas_item, GTK_TYPE_WIDGET)
static int n_items = 0;
static void
unstyle_item (CanvasItem *item)
{
if (item->provider)
{
gtk_style_context_remove_provider_for_display (gtk_widget_get_display (item->label), item->provider);
g_clear_object (&item->provider);
}
if (item->css_class)
{
gtk_widget_remove_css_class (item->label, item->css_class);
g_clear_pointer (&item->css_class, g_free);
}
}
static void
set_color (CanvasItem *item,
GdkRGBA *color)
{
char *css;
char *str;
GtkCssProvider *provider;
const char *name;
unstyle_item (item);
str = gdk_rgba_to_string (color);
name = gtk_widget_get_name (item->label);
css = g_strdup_printf ("#%s { background: %s; }", name, str);
provider = gtk_css_provider_new ();
gtk_css_provider_load_from_string (provider, css);
gtk_style_context_add_provider_for_display (gtk_widget_get_display (item->label), GTK_STYLE_PROVIDER (provider), 700);
item->provider = GTK_STYLE_PROVIDER (provider);
g_free (str);
g_free (css);
}
static void
set_css (CanvasItem *item,
const char *class)
{
unstyle_item (item);
gtk_widget_add_css_class (item->label, class);
item->css_class = g_strdup (class);
}
static gboolean
item_drag_drop (GtkDropTarget *dest,
const GValue *value,
double x,
double y)
{
GtkWidget *label = gtk_event_controller_get_widget (GTK_EVENT_CONTROLLER (dest));
CanvasItem *item = CANVAS_ITEM (gtk_widget_get_parent (gtk_widget_get_parent (label)));
if (G_VALUE_TYPE (value) == GDK_TYPE_RGBA)
set_color (item, g_value_get_boxed (value));
else if (G_VALUE_TYPE (value) == G_TYPE_STRING)
set_css (item, g_value_get_string (value));
return TRUE;
}
static void
apply_transform (CanvasItem *item)
{
GskTransform *transform;
graphene_rect_t bounds;
double x, y;
/* Add css padding and margin */
if (!gtk_widget_compute_bounds (item->label, item->label, &bounds))
return;
x = bounds.size.width / 2.;
y = bounds.size.height / 2.;
item->r = sqrt (x * x + y * y);
transform = gsk_transform_translate (NULL, &(graphene_point_t) { item->r, item->r });
transform = gsk_transform_rotate (transform, item->angle + item->delta);
transform = gsk_transform_translate (transform, &GRAPHENE_POINT_INIT (-x, -y));
gtk_fixed_set_child_transform (GTK_FIXED (item->fixed), item->label, transform);
gsk_transform_unref (transform);
}
static void
angle_changed (GtkGestureRotate *gesture,
double angle,
double delta)
{
CanvasItem *item = CANVAS_ITEM (gtk_event_controller_get_widget (GTK_EVENT_CONTROLLER (gesture)));
item->delta = angle / M_PI * 180.0;
apply_transform (item);
}
static void
rotate_done (GtkGesture *gesture)
{
CanvasItem *item = CANVAS_ITEM (gtk_event_controller_get_widget (GTK_EVENT_CONTROLLER (gesture)));
item->angle = item->angle + item->delta;
item->delta = 0;
}
static void
click_done (GtkGesture *gesture)
{
GtkWidget *item = gtk_event_controller_get_widget (GTK_EVENT_CONTROLLER (gesture));
GtkWidget *canvas = gtk_widget_get_parent (item);
GtkWidget *last_child;
last_child = gtk_widget_get_last_child (canvas);
if (item != last_child)
gtk_widget_insert_after (item, canvas, last_child);
}
/* GtkSettings treats `GTK_THEME=foo:dark` as theme name `foo`, variant `dark`,
* and our embedded CSS files let `foo-dark` work as an alias for `foo:dark`. */
static gboolean
has_dark_suffix (const char *theme)
{
return g_str_has_suffix (theme, ":dark") ||
g_str_has_suffix (theme, "-dark");
}
/* So we can make a good guess whether the current theme is dark by checking for
* either: it is suffixed `[:-]dark`, or Settings:…prefer-dark-theme is TRUE. */
static gboolean
theme_is_dark (void)
{
const char *env_theme;
GtkSettings *settings;
char *theme;
gboolean prefer_dark;
gboolean dark;
/* Like GtkSettings, 1st see if theme is overridden by environment variable */
env_theme = g_getenv ("GTK_THEME");
if (env_theme != NULL)
return has_dark_suffix (env_theme);
/* If not, test Settings:…theme-name in the same way OR :…prefer-dark-theme */
settings = gtk_settings_get_default ();
g_object_get (settings,
"gtk-theme-name", &theme,
"gtk-application-prefer-dark-theme", &prefer_dark,
NULL);
dark = prefer_dark || has_dark_suffix (theme);
g_free (theme);
return dark;
}
static void
canvas_item_init (CanvasItem *item)
{
char *text;
char *id;
GdkRGBA rgba;
GtkDropTarget *dest;
GtkGesture *gesture;
GType types[2] = { GDK_TYPE_RGBA, G_TYPE_STRING };
n_items++;
text = g_strdup_printf ("Item %d", n_items);
item->label = gtk_label_new (text);
gtk_widget_add_css_class (item->label, "canvasitem");
g_free (text);
item->fixed = gtk_fixed_new ();
gtk_widget_set_parent (item->fixed, GTK_WIDGET (item));
gtk_fixed_put (GTK_FIXED (item->fixed), item->label, 0, 0);
gtk_widget_add_css_class (item->label, "frame");
id = g_strdup_printf ("item%d", n_items);
gtk_widget_set_name (item->label, id);
g_free (id);
if (theme_is_dark ())
gdk_rgba_parse (&rgba, "blue");
else
gdk_rgba_parse (&rgba, "yellow");
set_color (item, &rgba);
item->angle = 0;
dest = gtk_drop_target_new (G_TYPE_INVALID, GDK_ACTION_COPY);
gtk_drop_target_set_gtypes (dest, types, G_N_ELEMENTS (types));
g_signal_connect (dest, "drop", G_CALLBACK (item_drag_drop), NULL);
gtk_widget_add_controller (GTK_WIDGET (item->label), GTK_EVENT_CONTROLLER (dest));
gesture = gtk_gesture_rotate_new ();
g_signal_connect (gesture, "angle-changed", G_CALLBACK (angle_changed), NULL);
g_signal_connect (gesture, "end", G_CALLBACK (rotate_done), NULL);
gtk_widget_add_controller (GTK_WIDGET (item), GTK_EVENT_CONTROLLER (gesture));
gesture = gtk_gesture_click_new ();
g_signal_connect (gesture, "released", G_CALLBACK (click_done), NULL);
gtk_widget_add_controller (GTK_WIDGET (item), GTK_EVENT_CONTROLLER (gesture));
}
static void
canvas_item_dispose (GObject *object)
{
CanvasItem *item = CANVAS_ITEM (object);
g_clear_pointer (&item->fixed, gtk_widget_unparent);
g_clear_pointer (&item->editor, gtk_widget_unparent);
G_OBJECT_CLASS (canvas_item_parent_class)->dispose (object);
}
static void
canvas_item_map (GtkWidget *widget)
{
CanvasItem *item = CANVAS_ITEM (widget);
GTK_WIDGET_CLASS (canvas_item_parent_class)->map (widget);
apply_transform (item);
}
static void
canvas_item_class_init (CanvasItemClass *class)
{
GObjectClass *object_class = G_OBJECT_CLASS (class);
GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (class);
object_class->dispose = canvas_item_dispose;
widget_class->map = canvas_item_map;
gtk_widget_class_set_layout_manager_type (widget_class, GTK_TYPE_BIN_LAYOUT);
gtk_widget_class_set_css_name (widget_class, "item");
}
static GtkWidget *
canvas_item_new (void)
{
CanvasItem *item = g_object_new (canvas_item_get_type (), NULL);
return GTK_WIDGET (item);
}
static GdkPaintable *
canvas_item_get_drag_icon (CanvasItem *item)
{
return gtk_widget_paintable_new (item->fixed);
}
static gboolean
canvas_item_is_editing (CanvasItem *item)
{
return item->editor != NULL;
}
static void
scale_changed (GtkRange *range,
CanvasItem *item)
{
item->angle = gtk_range_get_value (range);
apply_transform (item);
}
static void
text_changed (GtkEditable *editable,
GParamSpec *pspec,
CanvasItem *item)
{
gtk_label_set_text (GTK_LABEL (item->label), gtk_editable_get_text (editable));
apply_transform (item);
}
static void
canvas_item_stop_editing (CanvasItem *item)
{
GtkWidget *scale;
if (!item->editor)
return;
scale = gtk_widget_get_last_child (item->editor);
g_signal_handlers_disconnect_by_func (scale, scale_changed, item);
gtk_fixed_remove (GTK_FIXED (gtk_widget_get_parent (item->editor)), item->editor);
item->editor = NULL;
}
static void
canvas_item_start_editing (CanvasItem *item)
{
GtkWidget *canvas = gtk_widget_get_parent (GTK_WIDGET (item));
GtkWidget *entry;
GtkWidget *scale;
graphene_point_t p;
if (item->editor)
return;
item->editor = gtk_box_new (GTK_ORIENTATION_VERTICAL, 12);
entry = gtk_entry_new ();
gtk_editable_set_text (GTK_EDITABLE (entry),
gtk_label_get_text (GTK_LABEL (item->label)));
gtk_editable_set_width_chars (GTK_EDITABLE (entry), 12);
g_signal_connect (entry, "notify::text", G_CALLBACK (text_changed), item);
g_signal_connect_swapped (entry, "activate", G_CALLBACK (canvas_item_stop_editing), item);
gtk_box_append (GTK_BOX (item->editor), entry);
scale = gtk_scale_new_with_range (GTK_ORIENTATION_HORIZONTAL, 0, 360, 1);
gtk_scale_set_draw_value (GTK_SCALE (scale), FALSE);
gtk_range_set_value (GTK_RANGE (scale), fmod (item->angle, 360));
g_signal_connect (scale, "value-changed", G_CALLBACK (scale_changed), item);
gtk_box_append (GTK_BOX (item->editor), scale);
if (!gtk_widget_compute_point (GTK_WIDGET (item), canvas, &GRAPHENE_POINT_INIT (0, 0), &p))
graphene_point_init (&p, 0, 0);
gtk_fixed_put (GTK_FIXED (canvas), item->editor, p.x, p.y + 2 * item->r);
gtk_widget_grab_focus (entry);
}
typedef struct {
double x, y;
} Hotspot;
static GdkContentProvider *
prepare (GtkDragSource *source,
double x,
double y)
{
GtkWidget *canvas;
GtkWidget *item;
Hotspot *hotspot;
graphene_point_t p;
canvas = gtk_event_controller_get_widget (GTK_EVENT_CONTROLLER (source));
item = gtk_widget_pick (canvas, x, y, GTK_PICK_DEFAULT);
item = gtk_widget_get_ancestor (item, canvas_item_get_type ());
if (!item)
return NULL;
g_object_set_data (G_OBJECT (canvas), "dragged-item", item);
hotspot = g_new (Hotspot, 1);
if (!gtk_widget_compute_point (canvas, item, &GRAPHENE_POINT_INIT (x, y), &p))
graphene_point_init (&p, x, y);
hotspot->x = p.x;
hotspot->y = p.y;
g_object_set_data_full (G_OBJECT (canvas), "hotspot", hotspot, g_free);
return gdk_content_provider_new_typed (GTK_TYPE_WIDGET, item);
}
static void
drag_begin (GtkDragSource *source,
GdkDrag *drag)
{
GtkWidget *canvas;
CanvasItem *item;
GdkPaintable *paintable;
Hotspot *hotspot;
canvas = gtk_event_controller_get_widget (GTK_EVENT_CONTROLLER (source));
item = CANVAS_ITEM (g_object_get_data (G_OBJECT (canvas), "dragged-item"));
hotspot = (Hotspot *) g_object_get_data (G_OBJECT (canvas), "hotspot");
paintable = canvas_item_get_drag_icon (item);
gtk_drag_source_set_icon (source, paintable, hotspot->x, hotspot->y);
g_object_unref (paintable);
gtk_widget_set_opacity (GTK_WIDGET (item), 0.3);
}
static void
drag_end (GtkDragSource *source,
GdkDrag *drag)
{
GtkWidget *canvas;
GtkWidget *item;
canvas = gtk_event_controller_get_widget (GTK_EVENT_CONTROLLER (source));
item = g_object_get_data (G_OBJECT (canvas), "dragged-item");
g_object_set_data (G_OBJECT (canvas), "dragged-item", NULL);
gtk_widget_set_opacity (item, 1.0);
}
static gboolean
drag_cancel (GtkDragSource *source,
GdkDrag *drag,
GdkDragCancelReason reason)
{
return FALSE;
}
static gboolean
drag_drop (GtkDropTarget *target,
const GValue *value,
double x,
double y)
{
CanvasItem *item;
GtkWidget *canvas;
GtkWidget *last_child;
item = g_value_get_object (value);
canvas = gtk_widget_get_parent (GTK_WIDGET (item));
last_child = gtk_widget_get_last_child (canvas);
if (GTK_WIDGET (item) != last_child)
gtk_widget_insert_after (GTK_WIDGET (item), canvas, last_child);
gtk_fixed_move (GTK_FIXED (canvas), GTK_WIDGET (item), x - item->r, y - item->r);
return TRUE;
}
static void
new_item_cb (GtkWidget *button, gpointer data)
{
GtkWidget *canvas = data;
GtkWidget *popover;
GtkWidget *item;
GdkRectangle rect;
popover = gtk_widget_get_ancestor (button, GTK_TYPE_POPOVER);
gtk_popover_get_pointing_to (GTK_POPOVER (popover), &rect);
item = canvas_item_new ();
gtk_fixed_put (GTK_FIXED (canvas), item, rect.x, rect.y);
apply_transform (CANVAS_ITEM (item));
gtk_popover_popdown (GTK_POPOVER (gtk_widget_get_ancestor (button, GTK_TYPE_POPOVER)));
}
static void
edit_cb (GtkWidget *button, GtkWidget *child)
{
CanvasItem *item = CANVAS_ITEM (child);
if (button)
gtk_popover_popdown (GTK_POPOVER (gtk_widget_get_ancestor (button, GTK_TYPE_POPOVER)));
if (!canvas_item_is_editing (item))
canvas_item_start_editing (item);
}
static void
delete_cb (GtkWidget *button, GtkWidget *child)
{
GtkWidget *canvas = gtk_widget_get_parent (child);
gtk_fixed_remove (GTK_FIXED (canvas), child);
gtk_popover_popdown (GTK_POPOVER (gtk_widget_get_ancestor (button, GTK_TYPE_POPOVER)));
}
static void
pressed_cb (GtkGesture *gesture,
int n_press,
double x,
double y,
gpointer data)
{
GtkWidget *widget;
GtkWidget *child;
widget = gtk_event_controller_get_widget (GTK_EVENT_CONTROLLER (gesture));
child = gtk_widget_pick (widget, x, y, GTK_PICK_DEFAULT);
child = gtk_widget_get_ancestor (child, canvas_item_get_type ());
if (gtk_gesture_single_get_current_button (GTK_GESTURE_SINGLE (gesture)) == GDK_BUTTON_SECONDARY)
{
GtkWidget *menu;
GtkWidget *box;
GtkWidget *item;
menu = gtk_popover_new ();
gtk_widget_set_parent (menu, widget);
gtk_popover_set_has_arrow (GTK_POPOVER (menu), FALSE);
gtk_popover_set_pointing_to (GTK_POPOVER (menu), &(GdkRectangle){ x, y, 1, 1});
box = gtk_box_new (GTK_ORIENTATION_VERTICAL, 0);
gtk_popover_set_child (GTK_POPOVER (menu), box);
item = gtk_button_new_with_label ("New");
gtk_button_set_has_frame (GTK_BUTTON (item), FALSE);
g_signal_connect (item, "clicked", G_CALLBACK (new_item_cb), widget);
gtk_box_append (GTK_BOX (box), item);
item = gtk_separator_new (GTK_ORIENTATION_HORIZONTAL);
gtk_box_append (GTK_BOX (box), item);
item = gtk_button_new_with_label ("Edit");
gtk_button_set_has_frame (GTK_BUTTON (item), FALSE);
gtk_widget_set_sensitive (item, child != NULL && child != widget);
g_signal_connect (item, "clicked", G_CALLBACK (edit_cb), child);
gtk_box_append (GTK_BOX (box), item);
item = gtk_separator_new (GTK_ORIENTATION_HORIZONTAL);
gtk_box_append (GTK_BOX (box), item);
item = gtk_button_new_with_label ("Delete");
gtk_button_set_has_frame (GTK_BUTTON (item), FALSE);
gtk_widget_set_sensitive (item, child != NULL && child != widget);
g_signal_connect (item, "clicked", G_CALLBACK (delete_cb), child);
gtk_box_append (GTK_BOX (box), item);
gtk_popover_popup (GTK_POPOVER (menu));
}
}
static void
released_cb (GtkGesture *gesture,
int n_press,
double x,
double y,
gpointer data)
{
GtkWidget *widget;
GtkWidget *child;
CanvasItem *item;
widget = gtk_event_controller_get_widget (GTK_EVENT_CONTROLLER (gesture));
child = gtk_widget_pick (widget, x, y, 0);
if (!child)
return;
item = (CanvasItem *)gtk_widget_get_ancestor (child, canvas_item_get_type ());
if (!item)
return;
if (gtk_gesture_single_get_current_button (GTK_GESTURE_SINGLE (gesture)) == GDK_BUTTON_PRIMARY)
{
if (canvas_item_is_editing (item))
canvas_item_stop_editing (item);
else
canvas_item_start_editing (item);
}
}
static GtkWidget *
canvas_new (void)
{
GtkWidget *canvas;
GtkDragSource *source;
GtkDropTarget *dest;
GtkGesture *gesture;
canvas = gtk_fixed_new ();
gtk_widget_set_hexpand (canvas, TRUE);
gtk_widget_set_vexpand (canvas, TRUE);
source = gtk_drag_source_new ();
gtk_drag_source_set_actions (source, GDK_ACTION_MOVE);
g_signal_connect (source, "prepare", G_CALLBACK (prepare), NULL);
g_signal_connect (source, "drag-begin", G_CALLBACK (drag_begin), NULL);
g_signal_connect (source, "drag-end", G_CALLBACK (drag_end), NULL);
g_signal_connect (source, "drag-cancel", G_CALLBACK (drag_cancel), NULL);
gtk_widget_add_controller (canvas, GTK_EVENT_CONTROLLER (source));
dest = gtk_drop_target_new (GTK_TYPE_WIDGET, GDK_ACTION_MOVE);
g_signal_connect (dest, "drop", G_CALLBACK (drag_drop), NULL);
gtk_widget_add_controller (canvas, GTK_EVENT_CONTROLLER (dest));
gesture = gtk_gesture_click_new ();
gtk_gesture_single_set_button (GTK_GESTURE_SINGLE (gesture), 0);
g_signal_connect (gesture, "pressed", G_CALLBACK (pressed_cb), NULL);
g_signal_connect (gesture, "released", G_CALLBACK (released_cb), NULL);
gtk_widget_add_controller (canvas, GTK_EVENT_CONTROLLER (gesture));
return canvas;
}
static GdkContentProvider *
css_drag_prepare (GtkDragSource *source,
double x,
double y,
GtkWidget *button)
{
const char *class;
GdkPaintable *paintable;
class = (const char *)g_object_get_data (G_OBJECT (button), "css-class");
paintable = gtk_widget_paintable_new (button);
gtk_drag_source_set_icon (source, paintable, 0, 0);
g_object_unref (paintable);
return gdk_content_provider_new_typed (G_TYPE_STRING, class);
}
static GtkWidget *
css_button_new (const char *class)
{
GtkWidget *button;
GtkDragSource *source;
button = gtk_image_new ();
gtk_widget_set_size_request (button, 48, 32);
gtk_widget_add_css_class (button, class);
g_object_set_data (G_OBJECT (button), "css-class", (gpointer)class);
source = gtk_drag_source_new ();
g_signal_connect (source, "prepare", G_CALLBACK (css_drag_prepare), button);
gtk_widget_add_controller (button, GTK_EVENT_CONTROLLER (source));
return button;
}
typedef struct
{
GtkWidget parent_instance;
GdkRGBA color;
} ColorSwatch;
typedef struct
{
GtkWidgetClass parent_class;
} ColorSwatchClass;
G_DEFINE_TYPE (ColorSwatch, color_swatch, GTK_TYPE_WIDGET)
static GdkContentProvider *
color_swatch_drag_prepare (GtkDragSource *source,
double x,
double y,
ColorSwatch *swatch)
{
return gdk_content_provider_new_typed (GDK_TYPE_RGBA, &swatch->color);
}
static void
color_swatch_init (ColorSwatch *swatch)
{
GtkDragSource *source = gtk_drag_source_new ();
g_signal_connect (source, "prepare", G_CALLBACK (color_swatch_drag_prepare), swatch);
gtk_widget_add_controller (GTK_WIDGET (swatch), GTK_EVENT_CONTROLLER (source));
}
static void
color_swatch_snapshot (GtkWidget *widget,
GtkSnapshot *snapshot)
{
ColorSwatch *swatch = (ColorSwatch *)widget;
float w = gtk_widget_get_width (widget);
float h = gtk_widget_get_height (widget);
gtk_snapshot_append_color (snapshot, &swatch->color,
&GRAPHENE_RECT_INIT(0, 0, w, h));
}
void
color_swatch_measure (GtkWidget *widget,
GtkOrientation orientation,
int for_size,
int *minimum_size,
int *natural_size,
int *minimum_baseline,
int *natural_baseline)
{
if (orientation == GTK_ORIENTATION_HORIZONTAL)
*minimum_size = *natural_size = 48;
else
*minimum_size = *natural_size = 32;
}
static void
color_swatch_class_init (ColorSwatchClass *class)
{
GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (class);
widget_class->snapshot = color_swatch_snapshot;
widget_class->measure = color_swatch_measure;
gtk_widget_class_set_css_name (widget_class, "colorswatch");
}
static GtkWidget *
color_swatch_new (const char *color)
{
ColorSwatch *swatch = g_object_new (color_swatch_get_type (), NULL);
gdk_rgba_parse (&swatch->color, color);
return GTK_WIDGET (swatch);
}
static GtkWidget *window = NULL;
GtkWidget *
do_dnd (GtkWidget *do_widget)
{
if (!window)
{
GtkWidget *button;
GtkWidget *sw;
GtkWidget *canvas;
GtkWidget *box, *box2, *box3;
const char *colors[] = {
"red", "green", "blue", "magenta", "orange", "gray", "black", "yellow",
"white", "gray", "brown", "pink", "cyan", "bisque", "gold", "maroon",
"navy", "orchid", "olive", "peru", "salmon", "silver", "wheat",
NULL
};
int i;
int x, y;
GtkCssProvider *provider;
GString *css;
button = gtk_color_dialog_button_new (gtk_color_dialog_new ());
g_object_unref (g_object_ref_sink (button));
provider = gtk_css_provider_new ();
gtk_css_provider_load_from_resource (provider, "/dnd/dnd.css");
gtk_style_context_add_provider_for_display (gdk_display_get_default (),
GTK_STYLE_PROVIDER (provider),
800);
g_object_unref (provider);
css = g_string_new ("");
for (i = 0; colors[i]; i++)
g_string_append_printf (css, ".canvasitem.%s { background: %s; }\n", colors[i], colors[i]);
provider = gtk_css_provider_new ();
gtk_css_provider_load_from_string (provider, css->str);
gtk_style_context_add_provider_for_display (gdk_display_get_default (),
GTK_STYLE_PROVIDER (provider),
800);
g_object_unref (provider);
g_string_free (css, TRUE);
window = gtk_window_new ();
gtk_window_set_display (GTK_WINDOW (window),
gtk_widget_get_display (do_widget));
gtk_window_set_title (GTK_WINDOW (window), "Drag-and-Drop");
gtk_window_set_default_size (GTK_WINDOW (window), 640, 480);
g_object_add_weak_pointer (G_OBJECT (window), (gpointer *)&window);
box = gtk_box_new (GTK_ORIENTATION_VERTICAL, 0);
gtk_window_set_child (GTK_WINDOW (window), box);
box2 = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 0);
gtk_box_append (GTK_BOX (box), box2);
canvas = canvas_new ();
gtk_box_append (GTK_BOX (box2), canvas);
n_items = 0;
x = y = 40;
for (i = 0; i < 4; i++)
{
GtkWidget *item;
item = canvas_item_new ();
gtk_fixed_put (GTK_FIXED (canvas), item, x, y);
apply_transform (CANVAS_ITEM (item));
x += 150;
y += 100;
}
gtk_box_append (GTK_BOX (box), gtk_separator_new (GTK_ORIENTATION_HORIZONTAL));
sw = gtk_scrolled_window_new ();
gtk_scrolled_window_set_policy (GTK_SCROLLED_WINDOW (sw),
GTK_POLICY_AUTOMATIC,
GTK_POLICY_NEVER);
gtk_box_append (GTK_BOX (box), sw);
box3 = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 0);
gtk_widget_add_css_class (box3, "linked");
gtk_scrolled_window_set_child (GTK_SCROLLED_WINDOW (sw), box3);
for (i = 0; colors[i]; i++)
gtk_box_append (GTK_BOX (box3), color_swatch_new (colors[i]));
gtk_box_append (GTK_BOX (box3), css_button_new ("rainbow1"));
gtk_box_append (GTK_BOX (box3), css_button_new ("rainbow2"));
gtk_box_append (GTK_BOX (box3), css_button_new ("rainbow3"));
}
if (!gtk_widget_get_visible (window))
gtk_widget_set_visible (window, TRUE);
else
gtk_window_destroy (GTK_WINDOW (window));
return window;
}