一个快速扩展，应用mxcl的答案，使这特别容易(适应swift 2.3由旅行者):

extension UITextField {
    class func connectFields(fields:[UITextField]) -> Void {
        guard let last = fields.last else {
            return
        }
        for i in 0 ..< fields.count - 1 {
            fields[i].returnKeyType = .Next
            fields[i].addTarget(fields[i+1], action: "becomeFirstResponder", forControlEvents: .EditingDidEndOnExit)
        }
        last.returnKeyType = .Done
        last.addTarget(last, action: #selector(UIResponder.resignFirstResponder), forControlEvents: .EditingDidEndOnExit)
    }
}

它很容易使用:

UITextField.connectFields([field1, field2, field3])

扩展将设置返回按钮为“下一步”为所有但最后一个字段和“完成”为最后一个字段，并转移焦点/解散键盘时，这些被轻敲。

Swift < 2.3

extension UITextField {
    class func connectFields(fields:[UITextField]) -> Void {
        guard let last = fields.last else {
            return
        }
        for var i = 0; i < fields.count - 1; i += 1 {
            fields[i].returnKeyType = .Next
            fields[i].addTarget(fields[i+1], action: "becomeFirstResponder", forControlEvents: .EditingDidEndOnExit)
        }
        last.returnKeyType = .Done
        last.addTarget(last, action: "resignFirstResponder", forControlEvents: .EditingDidEndOnExit)
    }
}

斯威夫特3: 像这样使用-

UITextField.connectFields(fields: [field1, field2])

Extension:
    extension UITextField {
        class func connectFields(fields:[UITextField]) -> Void {
            guard let last = fields.last else {
                return
            }
            for i in 0 ..< fields.count - 1 {
                fields[i].returnKeyType = .next
                fields[i].addTarget(fields[i+1], action: #selector(UIResponder.becomeFirstResponder), for: .editingDidEndOnExit)
            }
            last.returnKeyType = .go
            last.addTarget(last, action: #selector(UIResponder.resignFirstResponder), for: .editingDidEndOnExit)
        }
    }

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..

一个更加一致和健壮的方法是使用NextResponderTextField 你可以完全从接口构建器中配置它，而不需要设置委托或使用view.tag。

你所需要做的就是

将UITextField的类类型设置为NextResponderTextField 然后设置nextResponderField的出口指向下一个responder它可以是任何UITextField或任何UIResponder子类。它也可以是一个UIButton，库足够智能，只有当它被启用时才会触发按钮的TouchUpInside事件。

下面是运行中的库:

我已经实现了在视图层次结构中通过Responders导航的动态解决方案。其思想是，在整个层次结构中搜索下一个可能的响应器，根据需要向前或向后搜索。

UIView搜索扩展:

UIView+Cat.h

- (UIResponder *)getNextFirstResponder;
- (UIResponder *)getPreviousFirstResponder;

UIView+Cat.m

- (UIResponder *)getPreviousFirstResponder {
    if (!self.superview) {
        return nil;
    }
    
    BOOL hasreachedself = NO;
    for (NSInteger i = self.superview.subviews.count-1; i >= 0; i--) {
        UIView *v = [self.superview.subviews objectAtIndex:i];
        if (v == self) {
            hasreachedself = YES;
            continue;
        }
        if (!hasreachedself) continue;
        
        if ([v canBecomeFirstResponder] && !v.hidden) {
            return v;
        }
        UIResponder *subResponder = [self getNextFirstResponderInView:v];
        if (subResponder) {
            return subResponder;
        }
    }
    
    //search hierachicaly in superviews
    return [self.superview getPreviousFirstResponder];
}

- (UIResponder *)getNextFirstResponder {
    if (!self.superview) {
        return nil;
    }
    
    BOOL hasreachedself = NO;
    for (UIView *v in self.superview.subviews) {
        if (v == self) {
            hasreachedself = YES;
            continue;
        }
        if (!hasreachedself) continue;
        
        if ([v canBecomeFirstResponder] && !v.hidden) {
            return v;
        }
        UIResponder *subResponder = [self getNextFirstResponderInView:v];
        if (subResponder) {
            return subResponder;
        }
    }
    
    //search hierachicaly in superviews
    return [self.superview getNextFirstResponder];
}

- (UIResponder *)getNextFirstResponderInView:(UIView *)view {
    if ([view canBecomeFirstResponder] && !view.hidden) {
        return view;
    }
    for (UIView *v in view.subviews) {
        UIResponder *subResponder = [self getNextFirstResponderInView:v];
        if (subResponder) {
            return subResponder;
        }
    }
    return nil;
}

用法:添加UIToolbar到UITextField / UITextView(在类别或子类中):

- (void)addToolbarInputAccessoryView {
    UIToolbar *toolbar = [[UIToolbar alloc] initWithFrame:CGRectZero];
    UIBarButtonItem *prev = [[UIBarButtonItem alloc] initWithImage:[UIImage systemImageNamed:@"chevron.up"] style:UIBarButtonItemStylePlain target:self action:@selector(moveToPreviousFirstResponder)];
    UIBarButtonItem *next = [[UIBarButtonItem alloc] initWithImage:[UIImage systemImageNamed:@"chevron.down"] style:UIBarButtonItemStylePlain target:self action:@selector(moveToNextFirstResponder)];
    UIBarButtonItem *space = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil];
    UIBarButtonItem *done = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(hideKeyboard)];
    toolbar.items = @[prev, next, space, done];
    
    if ([[UITextField appearance] keyboardAppearance] == UIKeyboardAppearanceDark) {
        toolbar.barStyle = UIBarStyleBlack;
        toolbar.translucent = YES;
        [toolbar setBarTintColor:[UIColor blackColor]];
        [toolbar setTintColor:[UIColor whiteColor]];
    }
    
    [toolbar sizeToFit];
    
    self.inputAccessoryView = toolbar;
}

- (void)hideKeyboard {
    [self resignFirstResponder];
}

- (void)moveToNextFirstResponder {
    UIResponder *next = [self getNextFirstResponder];
    if (next) {
        [next becomeFirstResponder];
    }
    else {
        [self resignFirstResponder];
    }
}

- (void)moveToPreviousFirstResponder {
    UIResponder *prev = [self getPreviousFirstResponder];
    if (prev) {
        [prev becomeFirstResponder];
    }
    else {
        [self resignFirstResponder];
    }
}

你可以使用IQKeyboardManager库来做到这一点。它处理所有的事情，你不需要任何额外的设置。IQKeyboardManager可以通过CocoaPods获得，要安装它，只需在Podfile中添加以下行:

pod 'IQKeyboardManager'

或 只需拖放IQKeyBoardManager目录从演示项目到您的项目。就是这样。 IQKeyBoardManager目录可以从https://github.com/hackiftekhar/IQKeyboardManager找到

Swift 3解决方案，使用UITextField的有序数组

func nextTextField() {
    let textFields = // Your textfields array

    for i in 0 ..< textFields.count{
        if let textfield = textFields[i], textfield.isFirstResponder{
            textfield.resignFirstResponder()
            if i+1 < textFields.count, let nextextfield = textFields[i+1]{
                nextextfield.becomeFirstResponder()
                return
            }
        }
    }
}