This event is fired when the component yields execution to the application.
This event is fired by TElSimpleSSLClient when the component needs to process Windows messages or give away the time slice to application.
Return true if SSL client can continue or false if blocking operation must be stopped.
Use this callback function if you wish to process all incoming messages yourself while TElSimpleSSLClient waits for synchronous server response. If this property is set to nil (null, Nothing), TElSimpleSSLClient uses its internal message loop to peek and dispatch messages.