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#include "demowidget.h"
#include "demolayout.h"
/* parent widget */
struct _DemoWidget
{
GtkWidget parent_instance;
gboolean backward; /* whether we go 0 -> 1 or 1 -> 0 */
gint64 start_time; /* time the transition started */
guint tick_id; /* our tick cb */
};
struct _DemoWidgetClass
{
GtkWidgetClass parent_class;
};
G_DEFINE_TYPE (DemoWidget, demo_widget, GTK_TYPE_WIDGET)
/* The widget is controlling the transition by calling
* demo_layout_set_position() in a tick callback.
*
* We take half a second to go from one layout to the other.
*/
#define DURATION (0.5 * G_TIME_SPAN_SECOND)
static gboolean
transition (GtkWidget *widget,
GdkFrameClock *frame_clock,
gpointer data)
{
DemoWidget *self = DEMO_WIDGET (widget);
DemoLayout *demo_layout = DEMO_LAYOUT (gtk_widget_get_layout_manager (widget));
gint64 now = g_get_monotonic_time ();
gtk_widget_queue_allocate (widget);
if (self->backward)
demo_layout_set_position (demo_layout, 1.0 - (now - self->start_time) / DURATION);
else
demo_layout_set_position (demo_layout, (now - self->start_time) / DURATION);
if (now - self->start_time >= DURATION)
{
self->backward = !self->backward;
demo_layout_set_position (demo_layout, self->backward ? 1.0 : 0.0);
/* keep things interesting by shuffling the positions */
if (!self->backward)
demo_layout_shuffle (demo_layout);
self->tick_id = 0;
return G_SOURCE_REMOVE;
}
return G_SOURCE_CONTINUE;
}
static void
clicked (GtkGestureClick *gesture,
guint n_press,
double x,
double y,
gpointer data)
{
DemoWidget *self = data;
if (self->tick_id != 0)
return;
self->start_time = g_get_monotonic_time ();
self->tick_id = gtk_widget_add_tick_callback (GTK_WIDGET (self), transition, NULL, NULL);
}
static void
demo_widget_init (DemoWidget *self)
{
GtkGesture *gesture;
gesture = gtk_gesture_click_new ();
g_signal_connect (gesture, "pressed", G_CALLBACK (clicked), self);
gtk_widget_add_controller (GTK_WIDGET (self), GTK_EVENT_CONTROLLER (gesture));
}
static void
demo_widget_dispose (GObject *object)
{
GtkWidget *child;
while ((child = gtk_widget_get_first_child (GTK_WIDGET (object))))
gtk_widget_unparent (child);
G_OBJECT_CLASS (demo_widget_parent_class)->dispose (object);
}
static void
demo_widget_class_init (DemoWidgetClass *class)
{
GObjectClass *object_class = G_OBJECT_CLASS (class);
GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (class);
object_class->dispose = demo_widget_dispose;
/* here is where we use our custom layout manager */
gtk_widget_class_set_layout_manager_type (widget_class, DEMO_TYPE_LAYOUT);
}
GtkWidget *
demo_widget_new (void)
{
return g_object_new (DEMO_TYPE_WIDGET, NULL);
}
void
demo_widget_add_child (DemoWidget *self,
GtkWidget *child)
{
gtk_widget_set_parent (child, GTK_WIDGET (self));
}
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