Changing in runtime the number of the component of the PickerView with NSUserDefaults

Hello everybody Im a newbie about iPhone programming I created an application with a tab bar.In one view there'开发者_开发知识库s a picker view in other view I put a slider where I want change the number of the components of the picker. Even if I use nsuserdefaults and then reloadAllcomponents the number of picker component doesn't change. Can someone help to resolve this issue? How can this two communicate without use setting bundle but only nsuserdefaults? Thanks

You need to [[NSUserDefaults standardUserDefaults] synchronize]; after writing to them in one class and before reading in other class?