Example of putting a widget ( specifically a GtkLabel ) in a GtkScrolledWindow.

scrolledwindow.c

/* scrolledwindow.c
 *
 * Example of putting a GtkLabel in a GtkScrolledWindow.
 *
 * COMPILE
 *
 * gcc `pkg-config --cflags gtk4` -o scrolledwindow scrolledwindow.c `pkg-config --libs gtk4`
 *
 * RUN
 *
 * ./scrolledwindow
 */

#include <gtk/gtk.h>

#if GLIB_CHECK_VERSION(2, 74, 0)
#define APP_FLAGS G_APPLICATION_DEFAULT_FLAGS
#else
#define APP_FLAGS G_APPLICATION_FLAGS_NONE
#endif

static void
activate( GtkApplication *app, gpointer user_data )
{
	GtkWidget *window, *vbox, *scrolled_window, *label;

	window = gtk_application_window_new( app );

	gtk_window_set_default_size (GTK_WINDOW (window), 100, 50);

	vbox = gtk_box_new( GTK_ORIENTATION_VERTICAL, 10 );

	scrolled_window = gtk_scrolled_window_new();

	label = gtk_label_new("<0.o>");

	gtk_scrolled_window_set_child( GTK_SCROLLED_WINDOW( scrolled_window ),
		label );

	gtk_box_append( GTK_BOX( vbox ), scrolled_window );

	gtk_scrolled_window_set_policy( GTK_SCROLLED_WINDOW( scrolled_window ),
		GTK_POLICY_NEVER,
		GTK_POLICY_ALWAYS );

	gtk_window_set_child( GTK_WINDOW( window ), vbox );

	gtk_widget_show( window );
}

int
main( int argc, char **argv )
{
	GtkApplication *app;
	int status;

	puts("Hover to the right of the label to see the scrollbar.");

	app = gtk_application_new( "org.gtk.example", APP_FLAGS );
	g_signal_connect( app, "activate", G_CALLBACK( activate ), NULL );
	status = g_application_run( G_APPLICATION( app ), argc, argv );
	g_object_unref( app );

	return status;
}