How do I set custom navigation bar(title + titleVi

问题:

I have a tabbed application with navigation controllers in tabs and view controller in them. All of them use the same navigation controller navigation bar: back button + logo image. Currently, I'm placing this code in every view controller:

- (void)viewDidLoad
{
  [super viewDidLoad];
  self.navigationItem.title = @"Back";
  UIImage *headerImage = [UIImage imageNamed:@"Logo.png"];
  self.navigationItem.titleView = [[[UIImageView alloc] initWithImage:headerImage] autorelease];
}

IMHO it's not the best way to do that. I'm thinking about using a category for UIViewController and to override viewDidLoad method, but every view controller has some additional code to execute in viewDidLoad, so I guess overriding is not the solution. What are the other ways?

回答1:

You could create a subclass of UIViewController, MyViewControllerWithBackButtonAndLogo (you can come up with a better name) then implement viewDidLoad to set up the navigation item. Make all your view controllers inherit from this base class. Then just make sure the view controllers call [super viewDidLoad] in their own implementations.

Also note that to set the back button title, you should not change the navigation item's title property, but set an appropriate backBarButtonItem.