返回按钮 BackButton

BackButton  (返回的Title修改方法)：

1. UIButton* backButton = [UIButton buttonWithType:101]; // left-pointing shape!

    [backButton addTarget:self action:@selector(backAction) forControlEvents:UIControlEventTouchUpInside];

    [backButton setTitle:@"Back123" forState:UIControlStateNormal];

    

    // create button item -- possible because UIButton subclasses UIView!

    UIBarButtonItem* backItem = [[UIBarButtonItem alloc] initWithCustomView:backButton];

    

    // add to toolbar, or to a navbar (you should only have one of these!)

   // [toolbar setItems:[NSArray arrayWithObject:backItem]];

    self.navigationItem.leftBarButtonItem = backItem;

2. UIBarButtonItem *backButton = [[UIBarButtonItem alloc] initWithTitle:@"Back321"  style:UIBarButtonItemStyleBordered  target:self  action:@selector(backToPrevious)];

    self.navigationItem.backBarButtonItem = backButton;

    [backButton release];

3.UIBarButtonItem *barButtonItem = [[UIBarButtonItem alloc] init];

    barButtonItem.title = @"Back123";

    self.navigationItem.backBarButtonItem = barButtonItem;

    [barButtonItem release];