FILTER EVENT

version 3

FILTER EVENT

You call the FILTER EVENT command from within an event-handling project method installed using the ON EVENT CALL command.

If an event-handling method calls FILTER EVENT, the current event is not passed to 4D.

This command allows you to remove the current event (i.e., click, keystroke) from the event queue, so 4D will not perform any additional treatment to the one you made in the event-handling project method.

WARNING: Avoid creating an event-handling method that only calls the FILTER EVENT command, because all the events are going to be ignored by 4D. In case you have an event-handling method with only the FILTER EVENT command, type Ctrl+Shift+Backspace (on Windows) or Command-Option-Shift-Control-Backspace (on Macintosh). This converts the On Event Call process into a normal process that does not get any events at all.

Special case: The FILTER EVENT command can also be used within a standard output form method when the form is displayed using the DISPLAY SELECTION or MODIFY SELECTION commands. In this specific case, the FILTER EVENT command allows you to filter double-clicks on the records (and in this way execute actions other than the opening of records in page mode).

To do this, place the following lines in the output form method:

   If(Form event=On Double Clicked)
      FILTER EVENT
      ...   `Process the double-click
   End if

See example for the command ON EVENT CALL.

ON EVENT CALL.