Your application may need to display initial values in the fields on a data form. There are two ways of doing this. The form is put on the screen by calling fm_proc() or fm_up(). If you know what the initial values should be before the form is put on the screen, you can simply set the underlying data variables for the fields to the desired values. When the form is displayed, Vermont Views will take the values in the underlying data variables and display them in the edit buffers of the fields on the form.
If, for some reason, you do not know what the initial values should be until after the form is on the screen, you can still display the initial values before the user gets control of the form. You can do this by writing a begin-form function that determines the initial values and updates the form. There are several different ways to update the form once it is on the screen. They are discussed later in this chapter.
