• Edit control,
• Combo Box control (standard or editable),
• Check Box and Radio Button controls,
• Rating control.

• Via the hint text (if the control is empty),
• By changing the control style,
• By showing the required input icon,
• By showing the explanation text.

• required input can be blocking.
  In this case, the input is checked when users leave the Edit control. If the user has not made an entry in the field, they will be blocked and will not be able to leave the field.
• required input can be non-blocking.
  In this case, the input is checked once all the fields have been filled out. This means users are not prevented from leaving a control.
  Controls with required input must be checked programmatically, with InvalidInputDetect.

Implementing required input

1. Open the control description window.
2. Go to the "Details" tab and select a value for "Required input":
   
   • "No" (default): The control will not highlight required input.
   • "Yes, blocking": The control will highlight required input in blocking mode. Users will not be able to leave the control without entering data.
   • "Yes, non-blocking": The control will highlight required input in non-blocking mode. Users may leave the control blank. The verification will be performed by the InvalidInputDetect function.
   Note: You can configure the required input highlighting options by clicking the button.
3. Validate the control description window.

Non-blocking required input

To handle required input in non-blocking mode, use InvalidInputDetect (for example, in the code of a button used to add elements to a database).
This function is used to check whether all required input controls in the current window have been filled in. Depending on the options set via the button, the controls that do not match the requirements are highlighted.

Required input settings: Text and display options

The button next to the "Required input" option allows you to define the visual changes of the control.

• Indication: Highlights the control if the input is empty BEFORE InvalidInputDetect is executed.
• Error: Highlights the control if the input is empty AFTER InvalidInputDetect is executed.

• Modificar estilo del control: This option changes the style of the control. The style used for the indication and for the error can be set in the "Style" tab of the control.
  
• Mostrar ícono de entrada obligatoria (ayuda): This option displays a specific icon in the control. The icon used and its position relative to the input area are set in the "Style" tab of the control ("Required input (indication/error): Explanation & icon", "Icon" button.
  
  If this option is selected, you can enter the explanation text. This text will be displayed when hovering over the control and when the icon is clicked. Note: If the explanation text is not specified, a default explanation text will be displayed.
• Mostrar texto de explicación: Displays the explanation text below the control. If the explanation text is not specified, a default explanation text will be displayed. Caution: This option modifies the interface. If this option is selected, the selected hint text is displayed directly below the control in the window being edited. It may be necessary to adapt the interface so that the control is displayed in its entirety.

• blocking.
  In this case, the mask is checked when users leave the control. If the mask does not match the expected input mask, users will not be able to leave the control.
• non-blocking.
  In this case, the mask is checked once all the fields have been filled out. This means users are not prevented from leaving a control.
  Controls with invalid input must be checked programmatically, with InvalidInputDetect.

Checking for invalid input

1. Define a variable of type InputMask that corresponds to the input mask to be applied to the control.
   Note: Don't forget to define the WLanguage procedure called by the CheckIfValidInput property of the InputMask variable. This procedure will be automatically called when the InvalidInputDetect function is used to determine if the text entered is valid.
2. Define the input mask to be used via the InputMask property in the code of the control.
3. Open the control description window.
4. In the "Details" tab, select a value for "Invalid input":
   
   • "No" (default): The control will not highlight invalid input.
   • "Yes, blocking": The control will highlight invalid input in blocking mode. Users will not be able to leave the control without entering valid data.
   • "Yes, non-blocking": The control will highlight invalid input in non-blocking mode. Users will be able to enter invalid data in the control. The verification will be performed by the InvalidInputDetect function.
   Note: You can configure the required input highlighting options by clicking the button.
5. Validate the control description window.

Novedad versión 2025
Note: The InvalidInput property is used to get and set the value of this option.

Handling invalid input in non-blocking mode

To handle invalid input in non-blocking mode, use InvalidInputDetect (for example, in the code of a button used to add elements to a database).
This function checks for invalid input in all Edit controls for which the "invalid" option is enabled in the current window. Depending on the options set via the button, the controls that do not match the requirements are highlighted.

Invalid input settings: Text and display options

The button next to the "Invalid input" option allows you to define the visual changes of the control.

• Modify control style: This option changes the style of the control. The style used for the different elements of the invalid input can be defined in the "Style" tab of the control.
  
• Display required input icon: This option displays a specific icon in the control. The icon used and its position relative to the input area are set in the "Style" tab of the control ("Invalid input: Explanation & icon", "Icon" button.
  
  If this option is selected, you can enter the explanation text. This text will be displayed when hovering over the control and when the icon is clicked. Note: If the explanation text is not specified, a default explanation text will be displayed.
• Display explanation text: This option displays the explanation text below the control. If the explanation text is not specified, a default explanation text will be displayed. Caution: This option modifies the interface. If this option is selected, the selected hint text is displayed directly below the control in the window being edited. It may be necessary to adapt the interface so that the control is displayed in its entirety.

Example

• The "Exit" event contains the following code:
  

  MySelf.InputMask = gMaskPhone

• The initialization code of the project contains the following code, which define the InputMask variable:
  

  gsMaskPhone is string = "99 99 99 99 99"
  gMaskPhone is InputMask
  
  gMaskPhone.CheckIfValidInput = CheckIfValidInput
  gMaskPhone.ValidateOnInput = ValidateDuringInput
  gMaskPhone.FormatOnInput = FormatDuringInput
  gMaskPhone.FormatOnExit = FormatDuringExit
  gMaskPhone.FormatOnEntry = FormatOnEntry
  gMaskPhone.FormatOnAssignment = FormatDuringAssignment
  
  		INTERNAL PROCEDURE CheckIfValidInput(sText is string): boolean
  		RETURN MatchRegularExpression(sText , "[0-9 ]*") _AND_ 
  				Length(StringFormat(sText, ccIgnoreInsideSpace)) = 10
  		END
  
  		INTERNAL PROCEDURE FormatDuringInput(LOCAL sTextBefore is string, 
  				LOCAL nCursorBefore is int, 
  				LOCAL nEndCursorBefore is int, sTextAfter is string, 
  					nCursorAfter is int, 
  					nEndCursorAfter is int)
  		IF Length(sTextBefore) > Length(sTextAfter) THEN RESULT
  		//No action if deleting
  		// if at the end
  		IF nEndCursorAfter = Length(sTextAfter) +1 THEN
  			// include " " if needed at this location
  			IF Middle(gsMaskPhone, nEndCursorAfter, 1) = " " THEN
  				sTextAfter += " "
  				nEndCursorAfter ++
  				nCursorAfter = nEndCursorAfter
  			END
  		END
  		END
  
  		INTERNAL PROCEDURE ValidateDuringInput(sText is string): boolean
  			RETURN MatchRegularExpression(sText , "[0-9 ]*")
  		END
  
  		INTERNAL PROCEDURE ValidateDuringExit(sText is string): boolean
  			RETURN MatchRegularExpression(sText , "[0-9 ]*")
  		END
  
  		INTERNAL PROCEDURE FormatDuringExit(sText_INOUT is string)
  			FormatStringToPhoneNumber(sText_INOUT)
  		END
  
  		INTERNAL PROCEDURE FormatOnEntry(sText_INOUT is string)
  			FormatStringToPhoneNumber(sText_INOUT)
  		END
  		INTERNAL PROCEDURE FormatDuringAssignment(sText_INOUT is string)
  			FormatStringToPhoneNumber(sText_INOUT)
  		END
  
  		INTERNAL PROCEDURE FormatStringToPhoneNumber(sText_INOUT is string)
  			sOut is string = ""
  			sText_INOUT = StringFormat(sText_INOUT, ccIgnoreInsideSpace + ccIgnoreSpace)
  			let nText = 1
  			FOR n = 1 _TO_ Length(gsMaskPhone)
  				IF nText > Length(sText_INOUT) THEN BREAK
  				IF gsMaskPhone [n] = " " THEN
  					sOut += " "
  				ELSE
  					sOut += sText_INOUT[nText]
  					nText ++
  				END
  			END
  			sText_INOUT = sOut
  		END

• The verification button contains the following code:
  

  InvalidInputDetect()

• Available properties:
  

  Novedad versión 2025 InvalidInput	La propiedad InvalidInput determina si se impide a los usuarios salir de un control cuando introducen datos no válidos.
  InvalidInputMessage	La propiedad InvalidInputMessage obtiene y establece el mensaje que se mostrará si el control contiene datos no válidos (máscara de entrada o valor fuera de límites).
  MandatoryInput	En MandatoryInput se utiliza para determinar si un control es obligatorio y para activar o desactivar la entrada de datos obligatoria.
  MandatoryInputMessage	La propiedad MandatoryInputMessage se utiliza para identificar y establecer el mensaje que se mostrará si el control se deja vacío (cuando la propiedad MandatoryInput está activada).
• Available functions:
  

  InvalidInputDetect	Detecta y señala un error en los controles con entrada obligatoria que se dejan vacíos y/o con datos no válidos.
  InvalidInputListControl	Crea una lista de controles con entrada obligatoria o datos no válidos.
  InvalidInputShowMessage	Muestra un error de entrada no válido para el control especificado.