Swift 4 for mxcl答案:

txtFirstname.addTarget(txtLastname, action: 
#selector(becomeFirstResponder), for: UIControlEvents.editingDidEndOnExit)

没有usings标签，也没有为nextField/nextTextField添加属性，你可以尝试模拟TAB，其中"testInput"是你当前的活动字段:

if ([textInput isFirstResponder])
    [textInput.superview.subviews enumerateObjectsAtIndexes:
     [NSIndexSet indexSetWithIndexesInRange:
      NSMakeRange([textInput.superview.subviews indexOfObject:textInput]+1,
                  [textInput.superview.subviews count]-[textInput.superview.subviews indexOfObject:textInput]-1)]
                                                    options:0 usingBlock:^(UIView *obj, NSUInteger idx, BOOL *stop) {
                                                        *stop = !obj.hidden && [obj becomeFirstResponder];
                                                    }];
if ([textInput isFirstResponder])
    [textInput.superview.subviews enumerateObjectsAtIndexes:
     [NSIndexSet indexSetWithIndexesInRange:
      NSMakeRange(0,
                  [textInput.superview.subviews indexOfObject:textInput])]
                                                    options:0 usingBlock:^(UIView *obj, NSUInteger idx, BOOL *stop) {
                                                        *stop = !obj.hidden && [obj becomeFirstResponder];
                                                    }];

这对我在Xamarin很有效。iOS / Monotouch。 将键盘按钮更改为Next，将控件传递给下一个UITextField，并将键盘隐藏在最后一个UITextField之后。

private void SetShouldReturnDelegates(IEnumerable<UIView> subViewsToScout )
{
  foreach (var item in subViewsToScout.Where(item => item.GetType() == typeof (UITextField)))
  {
    (item as UITextField).ReturnKeyType = UIReturnKeyType.Next;
    (item as UITextField).ShouldReturn += (textField) =>
    {
        nint nextTag = textField.Tag + 1;
        var nextResponder = textField.Superview.ViewWithTag(nextTag);
        if (null != nextResponder)
            nextResponder.BecomeFirstResponder();
        else
            textField.Superview.EndEditing(true); 
            //You could also use textField.ResignFirstResponder(); 

        return false; // We do not want UITextField to insert line-breaks.
    };
  }
}

在ViewDidLoad里面你会有:

如果你的TextFields没有标签设置它现在:

txtField1.Tag = 0;
txtField2.Tag = 1;
txtField3.Tag = 2;
//...

只是一个电话

SetShouldReturnDelegates(yourViewWithTxtFields.Subviews.ToList());
//If you are not sure of which view contains your fields you can also call it in a safer way:
SetShouldReturnDelegates(txtField1.Superview.Subviews.ToList());
//You can also reuse the same method with different containerViews in case your UITextField are under different views.

Swift 4 for mxcl答案:

txtFirstname.addTarget(txtLastname, action: 
#selector(becomeFirstResponder), for: UIControlEvents.editingDidEndOnExit)

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.

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..