Question

有一种情况是，用户在文本字段中输入两个字符，然后焦点应移至下一个文本字段。

以下是我使用的代码：

func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool {
        if let text = textField.text {

            let newStr = (text as NSString)
                .stringByReplacingCharactersInRange(range, withString: string)
            if newStr.isEmpty {
                return true
            }
            let intvalue = Int(newStr)

            if textField.tag == 101 { print("101") // only 2 integer
                 return (intvalue >= 0 && intvalue <= 99) ? true : false
            }
            else if textField.tag == 102 { print("102") // only 4 integer
                 return (intvalue >= 0 && intvalue <= 9999) ? true : false
            }

        }
        return true
    }

如何实现这一目标？

此外，数字键盘还没有完成按钮？

Answer 1

在用户输入2个字符后，您应该告诉下一个文本字段成为第一个响应者：

func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool {
    if (textField.text?.characters.count == 2) {
        textField.resignFirstResponder()
        yourNextTextField.becomeFirstResponder()
    }
    return true
}

Answer 2

Next和Done按钮的可能性是使用数字小键盘上方的UIToolbar。这样，您可以为这两个按钮分配一个函数，因为它们是UIBarButtonItem。

我在Objective C中有一些示例代码，如果您需要，我可以将其转换为Swift。

要创建UIToolbar，请使用：

UIToolbar *toolBar = [[UIToolbar alloc] initWithFrame:CGRectMake(0, 0, self.frame.size.width, 44)];
toolBar.barStyle = UIBarStyleBlackTranslucent;

UIBarButtonItem *doneButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(doneTouched:)];
UIBarButtonItem *nextButton = [[UIBarButtonItem alloc] initWithImage:[UIImage imageNamed:@"nextIcon"] style:UIBarButtonItemStylePlain target:self action:@selector(nextTouched:)];

// the middle button is to make the Done button align to right
[toolBar setItems:[NSArray arrayWithObjects:nextButton, [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil], doneButton, nil]];
picker1.inputAccessoryView = toolBar;
picker2.inputAccessoryView = toolBar;
picker3.inputAccessoryView = toolBar;

要实现Next功能，请使用以下代码：

-(void) nextTouched:(UIBarButtonItem*)itemClicked {
    if [([picker1 isFirstResponder])
        [picker2 becomeFirstResponder];
    else if [([picker2 isFirstResponder])
        picker3 becomeFirstResponder];
}

Answer 3

// This code in ViewDidLoad
txtCardDetails3.addTarget(self, action: #selector(VerifyCardViewController.textFieldDidChange(_:)), forControlEvents: UIControlEvents.EditingChanged)

func textFieldDidChange(textField: UITextField){

        let text = textField.text

        if textField.tag == 101 { // Set tag at design time
            if text?.utf16.count==2 {
                txtCardDetails4.becomeFirstResponder()
            }
        }
    }

// This code as it is 
 func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) -> Bool {
        if let text = textField.text {

            let newStr = (text as NSString)
                .stringByReplacingCharactersInRange(range, withString: string)
            if newStr.isEmpty {
                return true
            }
            let intvalue = Int(newStr)

            if textField.tag == 101 { print("101")
                 return (intvalue >= 0 && intvalue <= 99) ? true : false
            }
            else if textField.tag == 102 { print("102")
                 return (intvalue >= 0 && intvalue <= 9999) ? true : false
            }

        }
        return true
    }

Swift：从一个文本域移动到另一个文本域

3 个答案: