Primitive input (INPUT)
The primitive input operator creates an action that requests the client to input a value of a builtin class. The user can cancel the input, for example by pressing the Esc
key on the keyboard.
As with other value input operators, this operator allows to:
- specify initial object values
- specify main and alternative actions. The first is called if the input was successfully completed, the second if not (i.e. if the input was canceled).
- change a specified property
This operator can only be used in property change event handlers on a form.
Language
The syntax of the primitive input operator is described by the INPUT
operator.
Examples
changeCustomer (Order o) {
INPUT s = STRING[100] DO {
customer(o) <- s;
IF s THEN
MESSAGE 'Customer changed to ' + s;
ELSE
MESSAGE 'Customer dropped';
}
}
FORM order
OBJECTS o = Order
PROPERTIES(o) customer ON CHANGE changeCustomer(o)
;
testFile {
INPUT f = FILE DO { // requesting a dialog to select a file
open(f); // opening the selected file
}
}