Inside Macintosh: 3D Graphics Programming With QuickDraw 3D /

Chapter 17 - File Objects / File Objects Reference

Application-Defined Routines /

TQ3FileIdleMethod

You can define an idle method to receive occasional callbacks to your application during lengthy file operations.

typedef TQ3Status (*TQ3FileIdleMethod) (
TQ3FileObject file, 
const void *idlerData);

file

A file object.

idlerData

A pointer to an application-defined block of data.

DESCRIPTION

Your TQ3FileIdleMethod function is called occasionally during lengthy file operations. You can use an idle method to provide a method for the user to cancel the lengthy operation (for example, by clicking a button or pressing a key sequence such as Command-period).

If your idle method returns kQ3Success, QuickDraw 3D continues its current operation. If your idle method returns kQ3Failure, QuickDraw 3D cancels its current operation and returns kQ3ViewStatusCancelled the next time you call Q3View_EndWriting.

There is currently no way to indicate how often you want your idle method to be called. You can read the time maintained by the Operating System if you need to determine the amount of time that has elapsed since your idle method was last called.

SPECIAL CONSIDERATIONS

You must not call any QuickDraw 3D routines inside your idle method.