Java - Boton y ComboBox

private void btnColoresActionPerformed(java.awt.event.ActionEvent evt) {

        // TODO add your handling code here:

        DefaultComboBoxModel modelo = new DefaultComboBoxModel();

        String [] colores = {"rojo", "azul", "verde"};

        for(int i=0; i<colores.length;i++){

        modelo.addElement(colores[i]);

        comboBoxVentas.setModel(modelo);

          //  System.out.println(colores[i]);

}