gtk2/demos/gtk-demo/constraints2.c
Matthias Clasen d732c869c2 gtk-demo: Add keywords to demos
Add the names of the main widgets as keywords to
our demos, but also things like "game". This helps
finding relevant demos in our growing list. You
can now for example type "label", and find the
"error states" and "links" demos showing GtkLabel
features.
2020-09-13 15:00:14 -04:00

237 lines
8.8 KiB
C

/* Constraints/Interactive
* #Keywords: GtkConstraintLayout
*
* Demonstrate how constraints can be updates 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_constraints2 (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), "Constraints");
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_show (window);
else
gtk_window_destroy (GTK_WINDOW (window));
return window;
}