objective c - cocoa: How do I suppress NSPopUpButton automatic selection/synchronization? NSArrayController and NSMenu do not work -

i have nspopupbutton. whenever add or remove items it, first item gets automatically selected. want inhibit this; want nspopupbutton appear nothing selected, , not select until user selects something.

everything being constructed in code. (this backend; gui layout comes elsewhere.)

nscombobox already.

with nstableview, used nsarraycontroller , cocoa bindings, do:

[ac setselectsinsertedobjects:no];              // insertions [ac setavoidsemptyselection:no];                // deletions 

i tried nspopupbutton, however, , did not change behavior: first item still automatically selected.

i have tried accessing backing nsmenu @ on irc's suggestion , adding that; behavior did not change.

i noticed there's method on nspopupbutton, synchronizetitleandselecteditem, seems said nspopupbutton itself, don't see way disable it, either in nspopupbutton or nspopupbuttoncell. going have subclass nspopupbutton make method nothing? i'm not particularly attracted idea.

is there else i'm doing wrong? thanks.

speculation, possible answer:

if using arraycontroller, , have bound content not selectionindex, popup going keep selection index zero, if object @ index gets bumped elsewhere.

so bind selection index array controller well.