EZ_AddItemCallBack


NAME

EZ_AddItemCallBack,EZ_RemoveItemCallBack, EZ_RemoveAl- lItemCallBacks - register/remove callbacks associated to a display item

SYNOPSIS

#include <EZ.h> void EZ_AddItemCallBack( EZ_Item *item, int which, EZ_CallBack callback, void *clientdata, int location) void EZ_RemoveItemCallBack( EZ_Item *item, int which, EZ_CallBack callback, void *clientdata) void EZ_RemoveAllItemCallBacks( EZ_Item *item, int which)

ARGUMENTS

item Specifies a display item. callback Specifies a callback. clientdata Specifies an clientdata to be passed to the callback. which Specifies a callback list. location Specifies when the callback is to be called rel- ative to other previously callbacks.

DESCRIPTION

An callback is a procedure of the following prototype: void (* callback)(void *object, void *data) EZ_AddItemCallBack registers a callback to a item. There are two callback lists associated to a item: an EZ_CALL- BACK list and an EZ_DESTROY_CALLBACK list. Normal call- backs are called when a double Button1 click occurs on a item. Destroy callbacks are invoked at the time a item is destroyed. If location is 0, the callback will be put in front of all previously registered callbacks. If location is 1, the callback will be inserted at the end of all pre- viousely registered callbacks. EZ_RemoveItemCallBack deletes a callback from the speci- fied callback list. The specified callback will be deleted only if both the procedure and the client data match. EZ_RemoveAllCallBacks deletes all callbacks from the spec- ified callback list.

SEE ALSO

EZ_CreateItem(3), EZ_ConfigureItem(3), EZ_SetItemClientData(3)