我如何通过iPhone键盘上的“下一步”按钮浏览所有的文本字段?

最后一个文本字段应该关闭键盘。

我已经设置了IB按钮(下一步/完成),但现在我卡住了。

我实现了textFieldShouldReturn动作,但现在下一步和完成按钮关闭键盘。


当前回答

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.

其他回答

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.

如果有人想这样。我认为这是最接近问题所要求的要求

下面是我如何实现它

为需要设置的每个文本字段添加附件视图,使用

func setAccessoryViewFor(textField : UITextField)    {
    let toolBar = UIToolbar()
    toolBar.barStyle = .default
    toolBar.isTranslucent = true
    toolBar.sizeToFit()

    // Adds the buttons

    // Add previousButton
    let prevButton = UIBarButtonItem(title: "<", style: .plain, target: self, action: #selector(previousPressed(sender:)))
    prevButton.tag = textField.tag
    if getPreviousResponderFor(tag: textField.tag) == nil {
        prevButton.isEnabled = false
    }

    // Add nextButton
    let nextButton = UIBarButtonItem(title: ">", style: .plain, target: self, action: #selector(nextPressed(sender:)))
    nextButton.tag = textField.tag
    if getNextResponderFor(tag: textField.tag) == nil {
        nextButton.title = "Done"
    }

    let spaceButton = UIBarButtonItem(barButtonSystemItem: .flexibleSpace, target: nil, action: nil)
    toolBar.setItems([prevButton,spaceButton,nextButton], animated: false)
    toolBar.isUserInteractionEnabled = true
    textField.inputAccessoryView = toolBar
}

使用以下函数来处理轻拍

func nextPressed(sender : UIBarButtonItem) {
    if let nextResponder = getNextResponderFor(tag: sender.tag) {
        nextResponder.becomeFirstResponder()
    } else {
        self.view.endEditing(true)
    }

}

func previousPressed(sender : UIBarButtonItem) {
    if let previousResponder = getPreviousResponderFor(tag : sender.tag)  {
        previousResponder.becomeFirstResponder()
    }
}

func getNextResponderFor(tag : Int) -> UITextField? {
    return self.view.viewWithTag(tag + 1) as? UITextField
}

func getPreviousResponderFor(tag : Int) -> UITextField? {
    return self.view.viewWithTag(tag - 1) as? UITextField
}

您需要按您希望下一个/前一按钮响应的顺序给出textFields标记。

下面是一个没有授权的例子:

tf1.addTarget(tf2, action: #selector(becomeFirstResponder), for: .editingDidEndOnExit)
tf2.addTarget(tf3, action: #selector(becomeFirstResponder), for: .editingDidEndOnExit)

ObjC:

[tf1 addTarget:tf2 action:@selector(becomeFirstResponder) forControlEvents:UIControlEventEditingDidEndOnExit];
[tf2 addTarget:tf3 action:@selector(becomeFirstResponder) forControlEvents:UIControlEventEditingDidEndOnExit];

使用UIControlEventEditingDidEndOnExit UITextField动作工作(大部分是未知的)。

您还可以很容易地将其连接到故事板中,因此不需要委托或代码。

编辑:实际上我不知道如何在故事板中连接这个。becomeFirstResponder似乎不是这个control-event的一个提供的动作,这是一个遗憾。尽管如此,你可以将所有的文本字段连接到你的ViewController中的一个动作,然后决定哪个textField成为基于发送者的firstresponder(虽然它不像上面的编程解决方案那么优雅,所以IMO用viewDidLoad中的上述代码来做)。

这是一个简单的解决方案在swift,没有标签使用,没有故事板技巧…

只需使用这个扩展:

extension UITextField{

    func nextTextFieldField() -> UITextField?{
        //field to return
        var returnField : UITextField?
        if self.superview != nil{
            //for each view in superview
            for (_, view) in self.superview!.subviews.enumerate(){
                //if subview is a text's field
                if view.isKindOfClass(UITextField){
                    //cast curent view as text field
                    let currentTextField = view as! UITextField
                    //if text field is after the current one
                    if currentTextField.frame.origin.y > self.frame.origin.y{
                        //if there is no text field to return already
                        if returnField == nil {
                            //set as default return
                            returnField = currentTextField
                        }
                            //else if this this less far than the other
                        else if currentTextField.frame.origin.y < returnField!.frame.origin.y{
                            //this is the field to return
                            returnField = currentTextField
                        }
                    }
                }
            }
        }
        //end of the mdethod
        return returnField
    }

}

并调用它像这样(例如)与你的textfield委托:

func textFieldShouldReturn(textField: UITextField) -> Bool {
    textField.resignFirstResponder()
    textField.nextTextFieldField()?.becomeFirstResponder()
    return true
}

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!