ATTRIBUTE clause

DIALOG statement can have an optional ATTRIBUTE clause which can have only two attributes: UNBUFFERED and FIELD ORDER FORM.

FIELD ORDER FORM

If this attribute is absent, the cursor moves through the fields in the order in which they are specified in the corresponding INPUT, CONSTRUCT or INPUT ARRAY statement. If it is present, the field order is defined by the TABINDEX attribute value of each field:

UNBUFFERED

This attribute indicates that the DIALOG must be sensitive to the program variable changes. The UNBUFFERED attribute can have an optional Boolean value, e.g.: UNBUFFERED = 1 or UNBUFFERED = 0. The TRUE (1) value is equal to the keyword UNBUFFERED used by itself, the FALSE(0) value is equal to omitting the attribute.

 

The UNBUFFERED dialog mode allows you to avoid having to update the field buffer using the built-in functions before being able to use the value of the current field in a control clause. If the UNBUFFERED attribute is present or set to TRUE, the following actions are undertaken by the program, if any ON ACTION or ON KEY block is triggered:

• The value of the current field is written to the underlying variable.
• The statements in the ON ACTION or ON KEY clauses are executed.

 

If the UNBUFFERED attribute is absent or set to FALSE, the following actions sequence executed by the program, if any ON ACTION or ON KEY block is triggered:

• The value of the current field is written to the field buffer.
• The statements in the ON ACTION or ON KEY clauses are executed.
• The value in the current field is restored from the buffer and the input continues in the same field unless the previously executed clause moved the cursor to another field (i.e. with NEXT FIELD keywords).