iOS TabBarController didSelectViewController can't update The View in The Xib File. HELP!

[PizzaTray]

Since yesterday i was tryin to do a "simple" thing:

-I have a Tab Bar with number of tabs,
-When i choose some tab his viewController recognized that he was chosen,
and then i call for method in this viewController like so:

- (void)tabBarController:(UITabBarController *)tabBarController didSelectViewController:(UIViewController *)viewController {
	if(viewController == [self.tabBarController.viewControllers objectAtIndex:0]){
		NSLog(@"you have chose 0");
                [someViewController someMethod]; <<<<< updating some view items

The point is that its works! the "someMethod" called and run the code in it,
BUT THE VIEW NOT UPDATING! WHY??

delegate - ok.
tabbar selection - ok.
xib file to its viewController in this tab - ok.
method who calls - works ok.
view - doesn't get any update after the method-who-update-the-view was called.

any help....