Network Services Location Manager Miscellaneous Callbacks

• NSLFilterProcPtr

  Defines a pointer to a filter callback function. Your filter callback function determines if a URL should be displayed in the NSLStandardGetURL dialog box.

  typedef Boolean (*NSLURLFilterProcPtr)(
  char *url,
  Str255 displayString);
  

  If you name your function MyNSLFilterProcPtr, you would declare it like this:

  Boolean MyNSLURLFilterProcPtr (
  char* url,
  Str255 displayString);
  

  Parameters

  url

  A pointer to a string containing the URL to filter. Any data in a URL that follows the tag “?NAME=” has been removed from the URL.

  displayString

  A value of type Str255. If your filter callback returns TRUE, the URL pointed to by url will be listed in the dialog box displayed by NSLStandardGetURL. If you want to change the text of the URL, set displayString to the value you want.

  Discussion

  When calling NSLStandardGetURL, you can provide an NSLURLFilterProcPtr callback function for filtering the search results before they are displayed in the NSLStandardGetURL dialog box. Only those URLs for which your NSLURLFilterProcPtr callback function returns TRUE will appear in the right column of the dialog box displayed by NSLStandardGetURL. You can use the displayString parameter to modify the text of each URL that appears in the NSLStandardGetURL dialog box.

• NSLEventProcPtr

  Defines a pointer to a system event callback function.

  typedef void (*NSLEventFilterProcPtr)(
  EventRecord *newEvent,
  void *userContext);
  

  If you name your function MyNSLEventProcPtr, you would declare it like this:

  void MyNSLEventProcPtr (
  EventRecord *newEvent,
  void *userContext);
  

  Parameters

  newEvent

  A pointer to a structure of type EventRecord that describes the event that triggered the execution of this callback function.

  displayString

  An untyped pointer to arbitrary data that your application previously passed to NSLStandardGetURL.

  Discussion

  When calling NSLStandardGetURL, you can provide an NSLEventProcPtr callback function for receiving system events while NSLStandardGetURL displays its dialog box. Your system event callback function will receive events while the NSLStandardGetURL dialog box is being displayed. If you do not provide an NSLEventProcPtr callback function, your application will not receive events.

  When your NSLEventProcPtr callback function is called, it should process the event immediately and return.