Interface ComboBox.FormatEntryTextCallback

All Superinterfaces:
FunctionPointer
Enclosing class:
ComboBox
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 ComboBox.FormatEntryTextCallback extends FunctionPointer

Functional interface declaration of the FormatEntryTextCallback callback.

See Also:
  • Method Details

    • run

      String run(String path)

      Emitted to allow changing how the text in a combo box's entry is displayed.

      See Gtk.ComboBox:has-entry.

      Connect a signal handler which returns an allocated string representing path. That string will then be used to set the text in the combo box's entry. The default signal handler uses the text from the Gtk.ComboBox:entry-text-column model column.

      Here's an example signal handler which fetches data from the model and displays it in the entry.

      static char *
      format_entry_text_callback (GtkComboBox *combo,
                                  const char *path,
                                  gpointer     user_data)
      {
        GtkTreeIter iter;
        GtkTreeModel model;
        double       value;
      
        model = gtk_combo_box_get_model (combo);
      
        gtk_tree_model_get_iter_from_string (model, &iter, path);
        gtk_tree_model_get (model, &iter,
                            THE_DOUBLE_VALUE_COLUMN, &value,
                            -1);
      
        return g_strdup_printf ("%g", value);
      }
      
    • upcall

      default MemorySegment upcall(MemorySegment sourceComboBox, MemorySegment path)
      The upcall method is called from native code. The parameters are marshaled and run(String) is executed.
    • toCallback

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