Display Modes
Forms can be displayed in the following modes:
fill
Displays data on the screen and allows the data to be modified by the user. (Fill mode is the default if no mode is specified in the display statement.) Data displayed when the form first appears can come from one of two sources:
• Default values specified in the form's VIFRED definition
• Values placed in fields by the initialize statement
When you display a form in fill mode, all fields on the form are cleared before any initialization code is executed. Any values left in the form's fields from a previous display are cleared.
update
Displays whatever data is presently in the form. Unlike fill mode, fields in the form are not cleared before display. The user can change the data.
read
Specifies that the user can examine but not change the data on the form
query
Allows the user to enter a comparison operator (for example, = or < ), in addition to the data. Using these operators, your application can construct queries. The form must allow extra spaces in the fields for operators.