이 스피너는 스페이스바를 누르면 회전 동작을 멈추거나 시작합니다.
#include <gtk/gtk.h>
/*Global variable used to indicate active state of the
spinner. TRUE = active, FALSE = not-active. This is because
there isn't a current function for C that does this for us*/
gboolean active;
/*This is the callback function. It is a handler function
which reacts to the signal. In this case, it will cause the
spinner to start and stop according to how many times the user
presses the spacebar.*/
static gboolean
key_pressed_event (GtkWidget *widget,
GdkEvent *event,
gpointer user_data)
{
GtkWidget *spinner = user_data;
guint keyval;
/*Extracts the keyval from an event. And stores it in the variable
"keyval" (we give the function the address). In this case, the
event is GdkEventKey, a key press event*/
gdk_event_get_keyval (event, &keyval);
/*Grabbing the boolean value from the spinner*/
g_object_get (GTK_SPINNER (spinner), "active", &active, NULL);
if (keyval == GDK_KEY_space) {
if (active) {
gtk_spinner_stop (GTK_SPINNER (spinner));
}
else {
gtk_spinner_start (GTK_SPINNER (spinner));
}
}
return TRUE;
}
static void
activate (GtkApplication *app,
gpointer user_data)
{
GtkWidget *window;
GtkWidget *spinner;
/*Create a window with a title, border width and a default size*/
window = gtk_application_window_new (app);
gtk_window_set_title (GTK_WINDOW (window), "Spinner Example");
gtk_window_set_default_size (GTK_WINDOW (window), 200, 200);
gtk_container_set_border_width (GTK_CONTAINER(window), 30);
/*Create a spinner, with extra horizontal and vertical space*/
spinner = gtk_spinner_new ();
gtk_spinner_start (GTK_SPINNER (spinner));
gtk_container_add (GTK_CONTAINER (window), spinner);
/*Connecting the key-press-event signal to the callback*/
g_signal_connect (GTK_WINDOW (window), "key-press-event",
G_CALLBACK (key_pressed_event), spinner);
gtk_widget_show_all (window);
}
int
main (int argc, char **argv)
{
GtkApplication *app;
int status;
app = gtk_application_new ("org.gtk.example", G_APPLICATION_FLAGS_NONE);
g_signal_connect (app, "activate", G_CALLBACK (activate), NULL);
status = g_application_run (G_APPLICATION (app), argc, argv);
g_object_unref (app);
return status;
}
이 예제는 다음 참고자료가 필요합니다:
GtkApplication
GtkWindow
GObject
GtkSpinner