Full list mode of DISPLAY ARRAY
In order to handle short/medium result sets, use the full list mode of
DISPLAY ARRAY
.
Understanding the full list mode
In full list mode, DISPLAY ARRAY
uses a complete copy of the result set to be displayed in the
form array. The full list mode is typically used for a short or medium row set (10 - 100 rows).
In full list mode, the DISPLAY ARRAY
instruction uses a static or dynamic program
array defined with a record structure corresponding to (or to a part of ) a screen-array in the
current form.
The program array is filled with data rows before DISPLAY ARRAY
is executed,
typically with a FOREACH
loop when rows come from the database.
Consider using a dynamic array instead of a static array: By using a dynamic array the program
will only use the required memory resources, and the dialog will automatically detect the number of
rows from the dynamic array (array.getLength()
)
Full list mode example
DISPLAY ARRAY
in its simpler form: a dynamic
array is filled with database rows and contains the whole result set to be displayed in the
table:MAIN
DEFINE arr DYNAMIC ARRAY OF RECORD
id INTEGER,
fname CHAR(30),
lname CHAR(30)
END RECORD
DEFINE i INTEGER
DATABASE stores
OPEN FORM f1 FROM "custlist"
DISPLAY FORM f1
DECLARE c1 CURSOR FOR
SELECT customer_num, fname, lname FROM customer
LET i=1
FOREACH c1 INTO arr[i].*
LET i = i+1
END FOREACH
CALL arr.deleteElement(i)
DISPLAY ARRAY arr TO sa.* ATTRIBUTES(UNBUFFERED)
BEFORE ROW
MESSAGE "Moved to row ", arr_curr()
END DISPLAY
END MAIN