无法在导航栏上获得正确的栏按钮项目？

Question

I'm trying to have a button on the right side of my navigation controller - after this works I'd like the button to be as near to invisible as possible while still working. Maybe setting to high transparency or changing the colour to the navigation bar colour (whatever is cheaper for memory).

First though I can't seem to get a visible or working button on the right side of my navigation bar:

self.navigationController.navigationItem.rightBarButtonItem = 
[[UIBarButtonItem alloc] initWithTitle:@"coin" style:UIBarButtonItemStyleDone
target:self action:@selector(changeToInAppScene:)];

Answer 1

您必须分配给self.navigationItem.rightBarButtonItem （当前视图控制器的导航项），而不是self.navigationController.navigationItem.rightBarButtonItem 。

Answer 2

- (void)viewWillAppear:(BOOL)animated
{
    UIBarButtonItem *rightBar = [[UIBarButtonItem alloc]initWithTitle:@"Coin" style:UIBarButtonItemStylePlain target:self action:@selector(changeToInAppScene:)];
    self.navigationItem.rightBarButtonItem = rightBar;
}