我有一个OTP屏幕,我必须在4个Diff TextFields中输入4位密码的OTP,场景是这样的:
我已经管理了高达70%的工作,但只有当用户输入所有textField时,后退空间才有效。我正在粘贴我的代码。
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
// This allows numeric text only, but also backspace for deletes
if (string.length > 0 && ![[NSScanner scannerWithString:string] scanInt:NULL])
return NO;
NSUInteger oldLength = [textField.text length];
NSUInteger replacementLength = [string length];
NSUInteger rangeLength = range.length;
NSUInteger newLength = oldLength - rangeLength + replacementLength;
// This 'tabs' to next field when entering digits
if (newLength == 1) {
if (textField == _pin1)
{
[self performSelector:@selector(setNextResponder:) withObject:_pin2 afterDelay:0];
}
else if (textField ==_pin2)
{
[self performSelector:@selector(setNextResponder:) withObject:_pin3 afterDelay:0];
}
else if (textField == _pin3)
{
[self performSelector:@selector(setNextResponder:) withObject:_pin4 afterDelay:0];
}
}
//this goes to previous field as you backspace through them, so you don't have to tap into them individually
else if (oldLength > 0 && newLength == 0) {
if (textField ==_pin4)
{
[self performSelector:@selector(setNextResponder:) withObject:_pin3 afterDelay:0];
}
else if (textField == _pin3)
{
[self performSelector:@selector(setNextResponder:) withObject:_pin2 afterDelay:0];
}
else if (textField == _pin2)
{
[self performSelector:@selector(setNextResponder:) withObject:_pin1 afterDelay:0];
}
}
return newLength <= 1;
}
- (void)setNextResponder:(UITextField *)nextResponder
{
[nextResponder becomeFirstResponder];
}
工作:
答案 0 :(得分:7)
需要在UITextView
中的StoryBoard
中添加标记。
与textField1 = 101一样,textField2 = 102,textField3 = 103,textField4 = 104
将以下代码放入viewcontroller
。
- (BOOL)keyboardInputShouldDelete:(UITextField *)textField {
BOOL shouldDelete = YES;
if ([textField.text length] == 0 && [textField.text isEqualToString:@""]) {
long tagValue = textField.tag - 1;
UITextField *txtField = (UITextField*) [self.view viewWithTag:tagValue];
[txtField becomeFirstResponder];
}
return shouldDelete;
}
关注下一个UItextField
焦点的代码。
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
// This allows numeric text only, but also backspace for deletes
if (string.length > 0 && ![[NSScanner scannerWithString:string] scanInt:NULL])
return NO;
if ([textField.text length] == 0) {
[self performSelector:@selector(changeTextFieldFocusToNextTextField:) withObject:textField afterDelay:0.3];
}
return YES;
}
-(void)changeTextFieldFocusToNextTextField:(UITextField*)textField{
long tagValue = textField.tag + 1;
UITextField *txtField = (UITextField*) [self.view viewWithTag:tagValue];
[txtField becomeFirstResponder];
}
示例输出
答案 1 :(得分:2)
原因是当UITextField为empty
时,它不会检测到backspace event
。
因此,要在这种情况下检测退格事件,您必须Subclass
UITextField并覆盖deleteBackward
方法。
验证以下链接以获取更多详细信息。
Detect backspace in UITextField
编辑:代码已添加。
- 使用以下类对所有4个UITextfield进行子类化。
@protocol MyTextFieldDelegate <NSObject>
@optional
- (void)textFieldDidDelete:(UITextField *)textField;
@end
@interface MyTextField : UITextField<UIKeyInput>
@property (nonatomic, assign) id<MyTextFieldDelegate> myDelegate;
@end
@implementation MyTextField
- (void)deleteBackward {
[super deleteBackward];
if ([_myDelegate respondsToSelector:@selector(textFieldDidDelete:)]){
[_myDelegate textFieldDidDelete:self];
}
}
@end
- 为所有UITextFields设置委托给自己,并在类中采用MyTextFieldDelegate协议
_pin1.myDelegate=self;
_pin2.myDelegate=self;
_pin3.myDelegate=self;
_pin4.myDelegate=self;
- 实现textFieldDidDelete方法如下
- (void)textFieldDidDelete:(UITextField *)textField {
if (textField ==_pin4)
{
[self performSelector:@selector(setNextResponder:) withObject:_pin3 afterDelay:0];
}
else if (textField == _pin3)
{
[self performSelector:@selector(setNextResponder:) withObject:_pin2 afterDelay:0];
}
else if (textField == _pin2)
{
[self performSelector:@selector(setNextResponder:) withObject:_pin1 afterDelay:0];
}
}
希望这有帮助。
答案 2 :(得分:0)
对于Swift 3.x
class CodeConfirmController:ViewController,UITextFieldDelegate{
@IBOutlet weak var digitNum1: UITextField!
@IBOutlet weak var digitNum2: UITextField!
@IBOutlet weak var digitNum3: UITextField!
@IBOutlet weak var digitNum4: UITextField!
override func viewDidLoad() {
digitNum1.delegate = self
digitNum2.delegate = self
digitNum3.delegate = self
digitNum4.delegate = self
}
func keyboardInputShouldDelete(_ textField: UITextField) -> Bool {
let shouldDelete: Bool = true
if textField.text?.characters.count == 0 && (textField.text == "") {
let tagValue: Int = textField.tag - 1
let txtField: UITextField? = (view.viewWithTag(tagValue) as? UITextField)
txtField?.becomeFirstResponder()
}
return shouldDelete
}
func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
// This allows numeric text only, but also backspace for deletes
if (string.characters.count ) > 0 && !Scanner(string: string).scanInt32(nil) {
return false
}
if textField.text?.characters.count == 0 {
perform(#selector(self.changeTextFieldFocus(toNextTextField:)), with: textField, afterDelay: 0.1)
}
return true
}
func changeTextFieldFocus(toNextTextField textField: UITextField) {
let tagValue: Int = textField.tag + 1
let txtField: UITextField? = (view.viewWithTag(tagValue) as? UITextField)
txtField?.becomeFirstResponder()
}
}