SET-WAIT-STATE( ) method

Sets or cancels an ABL wait state that blocks user and system input.

Return type:

LOGICAL

Applies to:

SESSION system handle

 

Syntax 

SET-WAIT-STATE ( state-string )

state-string

A character-string expression that sets the wait state.

The value of state-string determines the wait state and the type of wait cursor displayed. The valid values are:

"GENERAL" — Displays the system-busy cursor

"COMPILER" — Displays the ABL compiler cursor

Input is blocked and the wait cursor is displayed until the wait state is cancelled. The null string ("") cancels the wait state.

The SET-WAIT-STATE( ) method accepts an arbitrary mouse pointer name (any string which is a valid argument to the LOAD-MOUSE-POINTER( ) method) as an argument, in addition to the "GENERAL", "COMPILER", and "" states. The return value is TRUE if the wait-state is set successfully; otherwise the return value is FALSE.

Note that this method is intended to provide user feedback for lengthy processing that involves no user input, such as compiling procedures, doing a time consuming database lookup, or some long CPU and memory operation like computing the value of π.

This method is not supported in character mode.

If an error occurs from this method, the AVM displays the error and terminates the wait state.

Caution:

Be sure that the processing you invoke after setting the wait state is guaranteed to cancel the wait state. Otherwise, the AVM remains in the wait state indefinitely. For example, do not place user input statements, such as SET or UPDATE, between the setting and cancelling of the wait state. Because the user cannot respond to these statements during the wait state, ABL I/O blocks indefinitely, preventing the wait state from being cancelled.