Display/Hide a Check-Box based on the value of a I/O field

Hello,

Hope everyone are good great !!!

I have a query on Selection-screen design.

How to display/hide a Check-Box based on the value of a input/output (I/O) field.

I have tried 'DYNP_VALUES_READ' in 'AT SELECTION-SCREEN' event event but this FM gets triggered only when the ENTER key is pressed.

Is there any alternate way available for this so that I can read the value of the field and display/hide the Check-Box in 'AT SELECTION-SCREEN OUTPUT' event by the use of Modif ID.

P.S. For example, If the user enters the value '1000' for the I/O field in the selection-screen (via F4 help or manually), the check-box should be visible else it should not be.

Many thanks in advance.

Warm Regards,

Yogesh Babu K.