首先在xib中设置键盘返回键，否则你可以在viewdidload中编写代码:

passWord.returnKeyType = UIReturnKeyNext;

-(BOOL)textFieldShouldReturn:(UITextField *)textField
{
    if(textField == eMail) {
        [textField resignFirstResponder];
        [userName becomeFirstResponder];
    }
    if (textField==userName) {
        [textField resignFirstResponder];
        [passWord becomeFirstResponder];
    }
    if (textField==passWord) {
        [textField resignFirstResponder];
        [country becomeFirstResponder];
    }
    if (textField==country) {
        [textField resignFirstResponder];
    }
    return YES;
}

在textFieldShouldReturn你应该检查你目前的文本域不是最后一个，当他们点击下一步，如果不是不要解散键盘..

首先在xib中设置键盘返回键，否则你可以在viewdidload中编写代码:

passWord.returnKeyType = UIReturnKeyNext;

-(BOOL)textFieldShouldReturn:(UITextField *)textField
{
    if(textField == eMail) {
        [textField resignFirstResponder];
        [userName becomeFirstResponder];
    }
    if (textField==userName) {
        [textField resignFirstResponder];
        [passWord becomeFirstResponder];
    }
    if (textField==passWord) {
        [textField resignFirstResponder];
        [country becomeFirstResponder];
    }
    if (textField==country) {
        [textField resignFirstResponder];
    }
    return YES;
}

退出一个文本字段后，调用[otherTextField becomeFirstResponder]，下一个字段获得焦点。

这实际上是一个棘手的问题，因为通常你还想滚动屏幕或以其他方式调整文本字段的位置，以便在编辑时容易看到。只要确保做大量的测试，以不同的方式进入和退出文本字段，并提前离开(总是给用户一个选项，取消键盘，而不是进入下一个字段，通常在导航栏中有“完成”)

在Mac OS X的Cocoa中，你有下一个响应器链，在那里你可以询问文本字段下一个控件应该有焦点。这就是在文本字段之间进行标签操作的原因。但由于iOS设备没有键盘，只有触摸，所以这一概念没有在Cocoa touch的过渡中幸存下来。

这很容易做到，只要有两个假设:

所有“tabbable”UITextFields都在同一个父视图上。 它们的“制表符顺序”由tag属性定义。

假设你可以重写textFieldShouldReturn:如下:

-(BOOL)textFieldShouldReturn:(UITextField*)textField
{
  NSInteger nextTag = textField.tag + 1;
  // Try to find next responder
  UIResponder* nextResponder = [textField.superview viewWithTag:nextTag];
  if (nextResponder) {
    // Found next responder, so set it.
    [nextResponder becomeFirstResponder];
  } else {
    // Not found, so remove keyboard.
    [textField resignFirstResponder];
  }
  return NO; // We do not want UITextField to insert line-breaks.
}

添加更多的代码，也可以忽略这些假设。

斯威夫特4.0

 func textFieldShouldReturn(_ textField: UITextField) -> Bool {
    let nextTag = textField.tag + 1
    // Try to find next responder
    let nextResponder = textField.superview?.viewWithTag(nextTag) as UIResponder!

    if nextResponder != nil {
        // Found next responder, so set it
        nextResponder?.becomeFirstResponder()
    } else {
        // Not found, so remove keyboard
        textField.resignFirstResponder()
    }

    return false
}

如果文本字段的superview是一个UITableViewCell那么下一个responder将是

let nextResponder = textField.superview?.superview?.superview?.viewWithTag(nextTag) as UIResponder!

我喜欢Anth0和Answerbot已经提出的面向对象解决方案。然而，我正在开发一个快速而小型的POC，所以我不想让子类和类别使事情变得混乱。

另一个简单的解决方案是创建一个字段的NSArray，并在按下next时查找下一个字段。不是面向对象的解决方案，而是快速、简单且易于实现。此外，您可以一目了然地查看和修改排序。

下面是我的代码(基于这个线程中的其他答案):

@property (nonatomic) NSArray *fieldArray;

- (void)viewDidLoad {
    [super viewDidLoad];

    fieldArray = [NSArray arrayWithObjects: firstField, secondField, thirdField, nil];
}

- (BOOL) textFieldShouldReturn:(UITextField *) textField {
    BOOL didResign = [textField resignFirstResponder];
    if (!didResign) return NO;

    NSUInteger index = [self.fieldArray indexOfObject:textField];
    if (index == NSNotFound || index + 1 == fieldArray.count) return NO;

    id nextField = [fieldArray objectAtIndex:index + 1];
    activeField = nextField;
    [nextField becomeFirstResponder];

    return NO;
}

I always return NO because I don't want a line break inserted. Just thought I'd point that out since when I returned YES it would automatically exit the subsequent fields or insert a line break in my TextView. It took me a bit of time to figure that out. activeField keeps track of the active field in case scrolling is necessary to unobscure the field from the keyboard. If you have similar code, make sure you assign the activeField before changing the first responder. Changing first responder is immediate and will fire the KeyboardWasShown event immediately.