GtkComboBox a widget used to choose from a list of items. @combobox: the object which received the signal. @Returns: @model: @model: @Returns: @combo_box: @width: @combo_box: @row_span: @combo_box: @column_span: @combo_box: @Returns: @combo_box: @index: @combo_box: @iter: @Returns: @combo_box: @iter: @combo_box: @Returns: @combo_box: @model: @Returns: @combo_box: @text: @combo_box: @position: @text: @combo_box: @text: @combo_box: @position: @combo_box: @combo_box: