238 lines
8.9 KiB
C
238 lines
8.9 KiB
C
|
/* Constraints/Interactive Constraints
|
||
|
|
* #Keywords: GtkConstraintLayout
|
||
|
|
*
|
||
|
|
* This example shows how constraints can be updated during user interaction.
|
||
|
|
* The vertical edge between the buttons can be dragged with the mouse.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <glib/gi18n.h>
|
||
|
|
#include <gtk/gtk.h>
|
||
|
|
|
||
|
|
G_DECLARE_FINAL_TYPE (InteractiveGrid, interactive_grid, INTERACTIVE, GRID, GtkWidget)
|
||
|
|
|
||
|
|
struct _InteractiveGrid
|
||
|
|
{
|
||
|
|
GtkWidget parent_instance;
|
||
|
|
|
||
|
|
GtkWidget *button1, *button2;
|
||
|
|
GtkWidget *button3;
|
||
|
|
GtkConstraintGuide *guide;
|
||
|
|
GtkConstraint *constraint;
|
||
|
|
};
|
||
|
|
|
||
|
|
G_DEFINE_TYPE (InteractiveGrid, interactive_grid, GTK_TYPE_WIDGET)
|
||
|
|
|
||
|
|
static void
|
||
|
|
interactive_grid_dispose (GObject *object)
|
||
|
|
{
|
||
|
|
InteractiveGrid *self = INTERACTIVE_GRID (object);
|
||
|
|
|
||
|
|
g_clear_pointer (&self->button1, gtk_widget_unparent);
|
||
|
|
g_clear_pointer (&self->button2, gtk_widget_unparent);
|
||
|
|
g_clear_pointer (&self->button3, gtk_widget_unparent);
|
||
|
|
|
||
|
|
G_OBJECT_CLASS (interactive_grid_parent_class)->dispose (object);
|
||
|
|
}
|
||
|
|
|
||
|
|
static void
|
||
|
|
interactive_grid_class_init (InteractiveGridClass *klass)
|
||
|
|
{
|
||
|
|
GObjectClass *object_class = G_OBJECT_CLASS (klass);
|
||
|
|
GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (klass);
|
||
|
|
|
||
|
|
object_class->dispose = interactive_grid_dispose;
|
||
|
|
|
||
|
|
gtk_widget_class_set_layout_manager_type (widget_class, GTK_TYPE_CONSTRAINT_LAYOUT);
|
||
|
|
}
|
||
|
|
|
||
|
|
static void
|
||
|
|
build_constraints (InteractiveGrid *self,
|
||
|
|
GtkConstraintLayout *manager)
|
||
|
|
{
|
||
|
|
self->guide = g_object_new (GTK_TYPE_CONSTRAINT_GUIDE, NULL);
|
||
|
|
gtk_constraint_layout_add_guide (manager, self->guide);
|
||
|
|
|
||
|
|
gtk_constraint_layout_add_constraint (manager,
|
||
|
|
gtk_constraint_new_constant (GTK_CONSTRAINT_TARGET (self->guide),
|
||
|
|
GTK_CONSTRAINT_ATTRIBUTE_WIDTH,
|
||
|
|
GTK_CONSTRAINT_RELATION_EQ,
|
||
|
|
0.0,
|
||
|
|
GTK_CONSTRAINT_STRENGTH_REQUIRED));
|
||
|
|
|
||
|
|
gtk_constraint_layout_add_constraint (manager,
|
||
|
|
gtk_constraint_new (NULL,
|
||
|
|
GTK_CONSTRAINT_ATTRIBUTE_START,
|
||
|
|
GTK_CONSTRAINT_RELATION_EQ,
|
||
|
|
GTK_CONSTRAINT_TARGET (self->button1),
|
||
|
|
GTK_CONSTRAINT_ATTRIBUTE_START,
|
||
|
|
1.0,
|
||
|
|
-8.0,
|
||
|
|
GTK_CONSTRAINT_STRENGTH_REQUIRED));
|
||
|
|
gtk_constraint_layout_add_constraint (manager,
|
||
|
|
gtk_constraint_new (GTK_CONSTRAINT_TARGET (self->button1),
|
||
|
|
GTK_CONSTRAINT_ATTRIBUTE_END,
|
||
|
|
GTK_CONSTRAINT_RELATION_EQ,
|
||
|
|
GTK_CONSTRAINT_TARGET (self->guide),
|
||
|
|
GTK_CONSTRAINT_ATTRIBUTE_START,
|
||
|
|
1.0,
|
||
|
|
0.0,
|
||
|
|
GTK_CONSTRAINT_STRENGTH_REQUIRED));
|
||
|
|
gtk_constraint_layout_add_constraint (manager,
|
||
|
|
gtk_constraint_new (GTK_CONSTRAINT_TARGET (self->button2),
|
||
|
|
GTK_CONSTRAINT_ATTRIBUTE_START,
|
||
|
|
GTK_CONSTRAINT_RELATION_EQ,
|
||
|
|
GTK_CONSTRAINT_TARGET (self->guide),
|
||
|
|
GTK_CONSTRAINT_ATTRIBUTE_END,
|
||
|
|
1.0,
|
||
|
|
0.0,
|
||
|
|
GTK_CONSTRAINT_STRENGTH_REQUIRED));
|
||
|
|
gtk_constraint_layout_add_constraint (manager,
|
||
|
|
gtk_constraint_new (GTK_CONSTRAINT_TARGET (self->button2),
|
||
|
|
GTK_CONSTRAINT_ATTRIBUTE_END,
|
||
|
|
GTK_CONSTRAINT_RELATION_EQ,
|
||
|
|
NULL,
|
||
|
|
GTK_CONSTRAINT_ATTRIBUTE_END,
|
||
|
|
1.0,
|
||
|
|
-8.0,
|
||
|
|
GTK_CONSTRAINT_STRENGTH_REQUIRED));
|
||
|
|
gtk_constraint_layout_add_constraint (manager,
|
||
|
|
gtk_constraint_new (NULL,
|
||
|
|
GTK_CONSTRAINT_ATTRIBUTE_START,
|
||
|
|
GTK_CONSTRAINT_RELATION_EQ,
|
||
|
|
GTK_CONSTRAINT_TARGET (self->button3),
|
||
|
|
GTK_CONSTRAINT_ATTRIBUTE_START,
|
||
|
|
1.0,
|
||
|
|
-8.0,
|
||
|
|
GTK_CONSTRAINT_STRENGTH_REQUIRED));
|
||
|
|
|
||
|
|
gtk_constraint_layout_add_constraint (manager,
|
||
|
|
gtk_constraint_new (GTK_CONSTRAINT_TARGET (self->button3),
|
||
|
|
GTK_CONSTRAINT_ATTRIBUTE_END,
|
||
|
|
GTK_CONSTRAINT_RELATION_EQ,
|
||
|
|
GTK_CONSTRAINT_TARGET (self->guide),
|
||
|
|
GTK_CONSTRAINT_ATTRIBUTE_START,
|
||
|
|
1.0,
|
||
|
|
0.0,
|
||
|
|
GTK_CONSTRAINT_STRENGTH_REQUIRED));
|
||
|
|
|
||
|
|
gtk_constraint_layout_add_constraint (manager,
|
||
|
|
gtk_constraint_new (NULL,
|
||
|
|
GTK_CONSTRAINT_ATTRIBUTE_TOP,
|
||
|
|
GTK_CONSTRAINT_RELATION_EQ,
|
||
|
|
GTK_CONSTRAINT_TARGET (self->button1),
|
||
|
|
GTK_CONSTRAINT_ATTRIBUTE_TOP,
|
||
|
|
1.0,
|
||
|
|
-8.0,
|
||
|
|
GTK_CONSTRAINT_STRENGTH_REQUIRED));
|
||
|
|
gtk_constraint_layout_add_constraint (manager,
|
||
|
|
gtk_constraint_new (GTK_CONSTRAINT_TARGET (self->button2),
|
||
|
|
GTK_CONSTRAINT_ATTRIBUTE_TOP,
|
||
|
|
GTK_CONSTRAINT_RELATION_EQ,
|
||
|
|
GTK_CONSTRAINT_TARGET (self->button1),
|
||
|
|
GTK_CONSTRAINT_ATTRIBUTE_BOTTOM,
|
||
|
|
1.0,
|
||
|
|
0.0,
|
||
|
|
GTK_CONSTRAINT_STRENGTH_REQUIRED));
|
||
|
|
gtk_constraint_layout_add_constraint (manager,
|
||
|
|
gtk_constraint_new (GTK_CONSTRAINT_TARGET (self->button3),
|
||
|
|
GTK_CONSTRAINT_ATTRIBUTE_TOP,
|
||
|
|
GTK_CONSTRAINT_RELATION_EQ,
|
||
|
|
GTK_CONSTRAINT_TARGET (self->button2),
|
||
|
|
GTK_CONSTRAINT_ATTRIBUTE_BOTTOM,
|
||
|
|
1.0,
|
||
|
|
0.0,
|
||
|
|
GTK_CONSTRAINT_STRENGTH_REQUIRED));
|
||
|
|
gtk_constraint_layout_add_constraint (manager,
|
||
|
|
gtk_constraint_new (GTK_CONSTRAINT_TARGET (self->button3),
|
||
|
|
GTK_CONSTRAINT_ATTRIBUTE_BOTTOM,
|
||
|
|
GTK_CONSTRAINT_RELATION_EQ,
|
||
|
|
NULL,
|
||
|
|
GTK_CONSTRAINT_ATTRIBUTE_BOTTOM,
|
||
|
|
1.0,
|
||
|
|
-8.0,
|
||
|
|
GTK_CONSTRAINT_STRENGTH_REQUIRED));
|
||
|
|
}
|
||
|
|
|
||
|
|
static void
|
||
|
|
drag_cb (GtkGestureDrag *drag,
|
||
|
|
double offset_x,
|
||
|
|
double offset_y,
|
||
|
|
InteractiveGrid *self)
|
||
|
|
{
|
||
|
|
GtkConstraintLayout *layout = GTK_CONSTRAINT_LAYOUT (gtk_widget_get_layout_manager (GTK_WIDGET (self)));
|
||
|
|
double x, y;
|
||
|
|
|
||
|
|
if (self->constraint)
|
||
|
|
{
|
||
|
|
gtk_constraint_layout_remove_constraint (layout, self->constraint);
|
||
|
|
g_clear_object (&self->constraint);
|
||
|
|
}
|
||
|
|
|
||
|
|
gtk_gesture_drag_get_start_point (drag, &x, &y);
|
||
|
|
self->constraint = gtk_constraint_new_constant (GTK_CONSTRAINT_TARGET (self->guide),
|
||
|
|
GTK_CONSTRAINT_ATTRIBUTE_LEFT,
|
||
|
|
GTK_CONSTRAINT_RELATION_EQ,
|
||
|
|
x + offset_x,
|
||
|
|
GTK_CONSTRAINT_STRENGTH_REQUIRED);
|
||
|
|
gtk_constraint_layout_add_constraint (layout, g_object_ref (self->constraint));
|
||
|
|
gtk_widget_queue_allocate (GTK_WIDGET (self));
|
||
|
|
}
|
||
|
|
|
||
|
|
static void
|
||
|
|
interactive_grid_init (InteractiveGrid *self)
|
||
|
|
{
|
||
|
|
GtkWidget *widget = GTK_WIDGET (self);
|
||
|
|
GtkGesture *drag;
|
||
|
|
|
||
|
|
self->button1 = gtk_button_new_with_label ("Child 1");
|
||
|
|
gtk_widget_set_parent (self->button1, widget);
|
||
|
|
gtk_widget_set_name (self->button1, "button1");
|
||
|
|
|
||
|
|
self->button2 = gtk_button_new_with_label ("Child 2");
|
||
|
|
gtk_widget_set_parent (self->button2, widget);
|
||
|
|
gtk_widget_set_name (self->button2, "button2");
|
||
|
|
|
||
|
|
self->button3 = gtk_button_new_with_label ("Child 3");
|
||
|
|
gtk_widget_set_parent (self->button3, widget);
|
||
|
|
gtk_widget_set_name (self->button3, "button3");
|
||
|
|
|
||
|
|
GtkLayoutManager *manager = gtk_widget_get_layout_manager (GTK_WIDGET (self));
|
||
|
|
build_constraints (self, GTK_CONSTRAINT_LAYOUT (manager));
|
||
|
|
|
||
|
|
drag = gtk_gesture_drag_new ();
|
||
|
|
g_signal_connect (drag, "drag-update", G_CALLBACK (drag_cb), self);
|
||
|
|
gtk_widget_add_controller (GTK_WIDGET (self), GTK_EVENT_CONTROLLER (drag));
|
||
|
|
}
|
||
|
|
|
||
|
|
GtkWidget *
|
||
|
|
do_constraints_interactive (GtkWidget *do_widget)
|
||
|
|
{
|
||
|
|
static GtkWidget *window;
|
||
|
|
|
||
|
|
if (!window)
|
||
|
|
{
|
||
|
|
GtkWidget *box, *grid;
|
||
|
|
|
||
|
|
window = gtk_window_new ();
|
||
|
|
gtk_window_set_display (GTK_WINDOW (window), gtk_widget_get_display (do_widget));
|
||
|
|
gtk_window_set_title (GTK_WINDOW (window), "Interactive Constraints");
|
||
|
|
gtk_window_set_default_size (GTK_WINDOW (window), 260, -1);
|
||
|
|
g_object_add_weak_pointer (G_OBJECT (window), (gpointer *)&window);
|
||
|
|
|
||
|
|
box = gtk_box_new (GTK_ORIENTATION_VERTICAL, 12);
|
||
|
|
gtk_window_set_child (GTK_WINDOW (window), box);
|
||
|
|
|
||
|
|
grid = g_object_new (interactive_grid_get_type (), NULL);
|
||
|
|
gtk_widget_set_hexpand (grid, TRUE);
|
||
|
|
gtk_widget_set_vexpand (grid, TRUE);
|
||
|
|
gtk_box_append (GTK_BOX (box), grid);
|
||
|
|
}
|
||
|
|
|
||
|
|
if (!gtk_widget_get_visible (window))
|
||
|
|
gtk_widget_set_visible (window, TRUE);
|
||
|
|
else
|
||
|
|
gtk_window_destroy (GTK_WINDOW (window));
|
||
|
|
|
||
|
|
return window;
|
||
|
|
}
|