navigation改变主题

[self.navigationController.navigationBar setTitleTextAttributes:[NSDictionary dictionaryWithObjectsAndKeys:[UIColor yellowColor],UITextAttributeTextColor, [UIColor colorWithRed:0.0 green:0.0 blue:0.0 alpha:0.6],UITextAttributeTextShadowColor,[UIFont fontWithName:@"Marion-Italic" size:24.0],UITextAttributeFont,nil]];