DISPLAY TO

The DISPLAY TO instruction displays data to form fields explicitly.

Syntax

DISPLAY expression [,...] TO field-spec [,...]
  [ ATTRIBUTES ( display-attribute [,...] ) ]
where field-spec is:
{ field-name
| table-name.*
| table-name.field-name
| screen-array[line].*
| screen-array[line].field-name
| screen-record.*
| screen-record.field-name
} [,...]
where display-attribute is:
{ BLACK | BLUE | CYAN | GREEN
| MAGENTA | RED | WHITE | YELLOW
| BOLD | DIM | NORMAL
| REVERSE | BLINK | UNDERLINE
}
  1. expression is any expression supported by the language.
  2. field-name is the identifier of a field of the current form.
  3. table-name is the identifier of a database table of the current form.
  4. screen-record is the identifier of a screen record of the current form.
  5. screen-array is the screen array that will be used in the form.

Usage

A DISPLAY TO statement copies the data from program variables to the form fields specified after the TO keyword.

When the program variables do not have the same names as the form fields, you must use the TO clause to explicitly map the variables to form fields using a screen record or screen array. You can list the fields individually, or you can use the screen-record.* or screen-record[n].* notation, where screen-record[n].* specifies all the fields in line n of a screen array.

In this example, the values in the p_items program record are displayed in the first row of the s_items screen array:
DISPLAY p_items.* TO s_items[1].*
The expanded list of screen fields must correspond in order and in number to the expanded list of identifiers after the DISPLAY keyword. Identifiers and their corresponding fields must have the same or compatible data types. For example, the next DISPLAY statement displays the values in the p_customer program record in fields of the s_customer screen record:
DISPLAY p_customer.* TO s_customer.*
For this example, the p_customer program record and the s_customer screen record require compatible declarations. The following DEFINE statement declares the p_customer program record:
DEFINE p_customer RECORD
  customer_num LIKE customer.customer_num,
  fname LIKE customer.fname,
  lname LIKE customer.lname,
  phone LIKE customer.phone 
END RECORD
This fragment of a form specification declares the s_customer screen record:
ATTRIBUTES
 f000 = customer.customer_num;
 f001 = customer.fname;
 f002 = customer.lname;
 f003 = customer.phone;
END

The DISPLAY TO instruction is usually not needed if the program is always in the context of a dialog controlling the form fields.

DISPLAY TO changes the touched flag

The DISPLAY TO statement changes the 'touched' status of the target fields. When you modify a field value with this instruction, the FIELD_TOUCHED() operator returns true and the ON CHANGE and ON ROW CHANGE triggers may be invoked if the current field value was changed with a DISPLAY TO.

In dialogs controlling field input such as INPUT or INPUT ARRAY, use the UNBUFFERED attribute to display data to fields automatically without changing the 'touched' status of fields. The UNBUFFERED clause will perform automatic form field and program variable synchronization. When using the UNBUFFERED mode, the touched flag can be set with DIALOG.setFieldTouched() if you want to get the same effect as a DISPLAY TO.

Specifying TTY attributes in the DISPLAY TO statement

The ATTRIBUTES clause temporarily overrides any default display attributes or any attributes specified in the OPTIONS or OPEN WINDOW statements for the fields. When the DISPLAY TO statement completes execution, the default display attributes are restored. In a DISPLAY TO statement, any screen attributes specified in the ATTRIBUTES clause apply to all the fields that you specify after the TO keyword.

The REVERSE, BLINK, INVISIBLE, and UNDERLINE attributes are not sensitive to the color or monochrome status of the terminal, if the terminal is capable of displaying these intensity modes. The ATTRIBUTES clause can include zero or more of the BLINK, REVERSE, and UNDERLINE attributes, and zero or one of the other attributes. That is, all of the attributes except BLINK, REVERSE, and UNDERLINE are mutually exclusive.

The DISPLAY TO statement ignores the INVISIBLE attribute, regardless of whether you specify it in the ATTRIBUTES clause.