Inside Macintosh: QuickTime /

Chapter 2 - Movie Toolbox / Movie Toolbox Reference

Application-Defined Functions / Custom Dialog Functions

MyDlgHook

A dialog hook function should have the following form:

pascal short MyDlgHook (short item, DialogPtr theDialog, 
                        Ptr myDataPtr);

item

The number of the item selected.

theDialog

A pointer to the dialog structure for the dialog box.

myDataPtr

A pointer to the optional data whose address is passed to CustomGetFilePreview.

DESCRIPTION

You supply a dialog hook function to handle user selections of items that you added to a dialog box. If you provide a dialog hook function, CustomGetFilePreview calls your function immediately after calling the Dialog Manager's ModalDialog function. It passes your function the item number returned by ModalDialog, a pointer to the dialog structure, and a pointer to the data received from your application, if any.

Your dialog hook function returns as its function result an integer that is either the item number passed to it or some other item number. If your dialog hook function does not handle a selection, it should pass the item number back to the Standard File Package for processing by setting its return value equal to the item number. If your dialog hook function does handle the selection, it should pass back sfHookNullEvent or the number of some other pseudo-item.

SEE ALSO

See Inside Macintosh: Files for another sample dialog hook function.