iOS7修改NavigationItem上的標題名字大小顏色

self.navigationController.navigationBar.titleTextAttributes = [NSDictionarydictionaryWithObjectsAndKeys:[UIFontsystemFontOfSize:10.0f],NSFontAttributeName, nil];

self.nav = [[[NavViewController alloc] initWithRootViewController:self.viewController] autorelease];

   [self.nav.navigationBar setBackgroundImage:[UIImage imageNamed:@"navbg"] forBarMetrics:UIBarMetricsDefault];

   NSDictionary *dict = [NSDictionary dictionaryWithObjectsAndKeys:[UIColor whiteColor],UITextAttributeTextColor,[UIColor blackColor],UITextAttributeTextShadowColor,[UIFont boldSystemFontOfSize:20.0],UITextAttributeFont,CGSizeMake(0, -1.0),UITextAttributeTextShadowOffset, nil];

   self.nav.navigationBar.titleTextAttributes = dict;