用代理方法取自定义取消键还是没有效果，cancel还是cancel，并没有变成取消。没有达到理想的效果。

- (void)navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated

{

 UIButton *cancelBtn = [[UIButton alloc]initWithFrame:CGRectMake(0,0,50,30)];

[cancelBtnsetTitle:@"取消" forState:(UIControlStateNormal)];

cancelBtn.backgroundColor = [UIColor redColor];

[cancelBtnaddTarget:self action:@selector(click) forControlEvents:(UIControlEventTouchUpInside)];

 UIBarButtonItem *btn = [[UIBarButtonItem alloc] initWithCustomView:cancelBtn];

[viewController.navigationItem setRightBarButtonItem:btn animated:NO]; 

}

后来想想应该和info配置有关系，真的如愿。打开info.plist文件，找到Localization native development region这个key，修改一下Value,就可以啦！