iphone - UINavigationItem.titleView 能否成为FirstResponder？

Question

我有一个自定义 UITextField 添加到 UINavigationItem.titleView。但它不是成为FirstResponder。为什么这样？

- (void) viewDidLoad
{
    [super viewDidLoad];
    UITextField *titleTextField = [[UITextField alloc] initWithFrame:CGRectMake(65.0f, 8.0f, 160.0f, 30.0f)];
    titleTextField.text = @"Untitled";
    titleTextField.textAlignment = UITextAlignmentCenter;
    titleTextField.textColor = [UIColor whiteColor];
    titleTextField.font = [UIFont boldSystemFontOfSize:20.0f];
    //titleTextField.backgroundColor = [UIColor redColor];
    titleTextField.contentVerticalAlignment = UIControlContentVerticalAlignmentCenter;
    titleTextField.delegate = self;
    titleTextField.tag = 2;
    self.navigationItem.titleView = titleTextField;
    [titleTextField becomeFirstResponder]
}

请指教。

在此先感谢，巴拉蒂。

Answer 1

尝试[self.navigationItem.titleView becomeFirstResponder];代替[titleTextField becomeFirstResponder];

Answer 2

您还需要遵守UITextFieldDelegate协议。我认为您没有遵守协议。

在 .h 文件中（例如）

@interface RootViewController : UITableViewController<UITextFieldDelegate>

@end

Answer 3

尝试这个：

[titleTextField becomeFirstResponder];

然后：

self.navigationItem.titleView = titleTextField;

告诉我是否有运气...