VISIBLE {IS} {TRUE         }
        {= } {FALSE        }

The VISIBLE phrase determines whether or not the control is shown on the screen. If the VISIBLE phrase is set to TRUE, the control is shown. If it is set to FALSE, the control is invisible. If visible-state is used instead, then its value determines whether the control is shown. Any non-zero value indicates that the control is visible; zero indicates that it is invisible. Controls that are invisible do not appear on the screen and cannot be used. They continue to exist, however, and can be made visible subsequently in the program. If the VISIBLE phrase is omitted, then the control is initially made visible.