objective c - How to change the value of an item when other item changes in NSTableView? -

i have populated nstableview using binding nsarraycontroller

https://www.dropbox.com/s/igx8ttdfvi2tt09/ss.png

now when user changes 480 (in column width) 240 want change height value 270 185 accordingly.

what correct way this?

can help?

thanks

anand

just override setters each height , width , change other's value.

in other words, if both height , width properties of same object, have setheight call setwidth, etc.

the easiest way if have third property reflects relationship wish height , width have, such aspectratio.

alternately overriding setters, if want calculation based on previous value of height or width, register kvo changes in both keypaths options:(nskeyvalueobservingoptionnew | nskeyvalueobservingoptionold) , in observevalueforkeypath you'd change dictionary both old , new values, calculate how user scaled value , scale other value accordingly (while careful avoid triggering kvo when doing so). see registering kvo observing in kvo programming guide. kvo more difficult , prone error, i'd avoid , maintain consistency in data model through overriding setters.