Interface SpinButton.OutputCallback

All Superinterfaces:
FunctionPointer
Enclosing class:
SpinButton
Functional Interface:
This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.
@FunctionalInterface public static interface SpinButton.OutputCallback extends FunctionPointer

Functional interface declaration of the OutputCallback callback.

See Also:

  • Method Summary

    Modifier and Type
    Method
    Description
    boolean
    run()
    Emitted to tweak the formatting of the value for display.
    default MemorySegment
    toCallback(Arena arena)
    Creates a native function pointer to the upcall(MemorySegment) method.
    default int
    upcall(MemorySegment sourceSpinButton)
    The upcall method is called from native code.

  • Method Details

    • run

      boolean run()

      Emitted to tweak the formatting of the value for display.

      // show leading zeros
static gboolean
on_output (GtkSpinButton *spin,
           gpointer       data)
{
   char *text;
   int value;

   value = gtk_spin_button_get_value_as_int (spin);
   text = g_strdup_printf ("%02d", value);
   gtk_editable_set_text (GTK_EDITABLE (spin), text):
   g_free (text);

   return TRUE;
}

    • upcall

      default int upcall(MemorySegment sourceSpinButton)
      The upcall method is called from native code. The parameters are marshaled and run() is executed.

    • toCallback

      default MemorySegment toCallback(Arena arena)
      Creates a native function pointer to the upcall(MemorySegment) method.
      Specified by:
      toCallback in interface FunctionPointer
      Parameters:
      arena - the arena in which the function pointer is allocated
      Returns:
      the native function pointer