EvtHandler::FindNextHandlerOfClass

Section: ET++ method description (n)
Updated: automatically Fri Mar 15 14:09:27 1991
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NAME

EvtHandler::FindNextHandlerOfClass - instance method

TEMPLATE

aNextHandler = EvtHandler * FindNextHandlerOfClass(Class * desiredClass)

SPECIFIERS

public

DESCRIPTION

FindNextHandlerOfClass follows the event handler chain and returns the first handler which IsKindOf the desiredClass (see the macro IsKindOf). If there is no such handler NULL is returned. FindNextHandlerOfClass is used, for example, by the method View::GetDocument.
Compare this method with the method VObject::FindContainerOfClass.

ARGUMENTS

Class * desiredClass: the desired class of the searched handler. Classes can be specified with the macro Meta, e.g. Meta(Document).

RETURN ARGUMENT

EvtHandler * aNextHandler: the first event handler in the chain which is kind of the desiredClass or NULL

FILES

implementation:: EvtHandler.C

KNOWN PROBLEMS

Testing starts with this and not directly with the next handler. For example, if this is a View, then FindNextHandlerOfClass(Meta(View)) again returns this. A workaround is to start the search directly with the next handler:

View *nextView = NULL;
if (GetNextHandler())
    nextView = (View*)GetNextHandler()->FindNextHandlerOfClass(Meta(View));

This document was created by man2html, using the manual pages.
Time: 00:40:27 GMT, March 30, 2022