# Class Validator

java.lang.Object
com.codename1.ui.validation.Validator

public class Validator extends Object

Binds validation constraints to form elements, when validation fails it can be highlighted directly on the component via an emblem or change of the UIID (to original UIID name + "Invalid" e.g. "TextFieldInvalid"). Validators just run thru a set of Constraint objects to decide if validation succeeded or failed.

It's possible to create any custom logic of validation. Example (see this discussion on StackOverflow):

    Form hi = new Form("Phone Validator", BoxLayout.y());
    TextField phone = new TextField("", "Phone");
    Validator val = new Validator();
    val.addConstraint(phone, new Constraint() {
      public  boolean isValid(Object value) {
        String v = (String)value;
        for (int i = 0; i < v.length(); i++) {
          char c = v.charAt(i);
          if ((c >= '0' && c <= '9') || c == '+' || c == '-') {
            continue;
          }
          return false;
        }
        return true;
      }
      public String getDefaultFailMessage() {
        return "Must be valid phone number";
      }
    });
    hi.add(phone);
    hi.show();

- ## Nested Class Summary

  Nested Classes
  Modifier and Type
  Class
  Description
  `static enum`
  `Validator.HighlightMode`
  Indicates the validation failure modes

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `Validator()`
  Default constructor

- ## Method Summary

  Modifier and Type
  Method
  Description
  `Validator`
  `addConstraint(Component cmp, Constraint... c)`
  Places a constraint on the validator, returns this object so constraint additions can be chained.
  `Validator`
  `addSubmitButtons(Component... cmp)`
  Submit buttons (or any other component type) can be disabled until all components contain a valid value.
  `void`
  `bindDataListener(Component cmp)`
  Binds an event listener to the given component
  `protected Object`
  `getComponentValue(Component cmp)`
  Returns the value of the given component, this can be overriden to add support for custom built components
  `static float`
  `getDefaultValidationEmblemPositionX()`
  The position of the validation emblem on the component as X/Y values between 0 and 1 where 0 indicates the start of the component and 1 indicates its end on the given axis.
  `static float`
  `getDefaultValidationEmblemPositionY()`
  The position of the validation emblem on the component as X/Y values between 0 and 1 where 0 indicates the start of the component and 1 indicates its end on the given axis.
  `static Image`
  `getDefaultValidationFailedEmblem()`
  The emblem that will be drawn on top of the component to indicate the validation failure
  `static Validator.HighlightMode`
  `getDefaultValidationFailureHighlightMode()`
  Indicates the default mode in which validation failures are expressed
  `String`
  `getErrorMessage(Component cmp)`
  Returns the validation error message for the given component or null if no such message exists
  `String`
  `getErrorMessageUIID()`
  Error message UIID defaults to DialogBody.
  `float`
  `getValidationEmblemPositionX()`
  The position of the validation emblem on the component as X/Y values between 0 and 1 where 0 indicates the start of the component and 1 indicates its end on the given axis.
  `float`
  `getValidationEmblemPositionY()`
  The position of the validation emblem on the component as X/Y values between 0 and 1 where 0 indicates the start of the component and 1 indicates its end on the given axis.
  `Image`
  `getValidationFailedEmblem()`
  The emblem that will be drawn on top of the component to indicate the validation failure
  `Validator.HighlightMode`
  `getValidationFailureHighlightMode()`
  Indicates the default mode in which validation failures are expressed
  `boolean`
  `isShowErrorMessageForFocusedComponent()`
  Indicates whether an error message should be shown for the focused component
  `boolean`
  `isValid()`
  Returns true if all the constraints are currently valid
  `static boolean`
  `isValidateOnEveryKey()`
  Indicates whether validation should occur on every key press (data change listener) or action performed (editing completion)
  `static void`
  `setDefaultValidationEmblemPositionX(float aDefaultValidationEmblemPositionX)`
  The position of the validation emblem on the component as X/Y values between 0 and 1 where 0 indicates the start of the component and 1 indicates its end on the given axis.
  `static void`
  `setDefaultValidationEmblemPositionY(float aDefaultValidationEmblemPositionY)`
  The position of the validation emblem on the component as X/Y values between 0 and 1 where 0 indicates the start of the component and 1 indicates its end on the given axis.
  `static void`
  `setDefaultValidationFailedEmblem(Image aDefaultValidationFailedEmblem)`
  The emblem that will be drawn on top of the component to indicate the validation failure
  `static void`
  `setDefaultValidationFailureHighlightMode(Validator.HighlightMode aDefaultValidationFailureHighlightMode)`
  Indicates the default mode in which validation failures are expressed
  `void`
  `setErrorMessageUIID(String errorMessageUIID)`
  Error message UIID defaults to DialogBody.
  `void`
  `setShowErrorMessageForFocusedComponent(boolean showErrorMessageForFocusedComponent)`
  Indicates whether an error message should be shown for the focused component
  `static void`
  `setValidateOnEveryKey(boolean aValidateOnEveryKey)`
  Indicates whether validation should occur on every key press (data change listener) or action performed (editing completion)
  `void`
  `setValidationEmblemPositionX(float validationEmblemPositionX)`
  The position of the validation emblem on the component as X/Y values between 0 and 1 where 0 indicates the start of the component and 1 indicates its end on the given axis.
  `void`
  `setValidationEmblemPositionY(float validationEmblemPositionY)`
  The position of the validation emblem on the component as X/Y values between 0 and 1 where 0 indicates the start of the component and 1 indicates its end on the given axis.
  `void`
  `setValidationFailedEmblem(Image validationFailedEmblem)`
  The emblem that will be drawn on top of the component to indicate the validation failure
  `void`
  `setValidationFailureHighlightMode(Validator.HighlightMode validationFailureHighlightMode)`
  Indicates the default mode in which validation failures are expressed
  `protected void`
  `validate(Component cmp)`
  Validates and highlights an individual component

  ### Methods inherited from class Object

  `clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- ## Constructor Details

  - ### Validator

    public Validator()
    Default constructor

- ## Method Details

  - ### getDefaultValidationFailureHighlightMode

    public static Validator.HighlightMode getDefaultValidationFailureHighlightMode()

    Indicates the default mode in which validation failures are expressed

    ###### Returns

    the defaultValidationFailureHighlightMode

  - ### setDefaultValidationFailureHighlightMode

    public static void setDefaultValidationFailureHighlightMode(Validator.HighlightMode aDefaultValidationFailureHighlightMode)

    Indicates the default mode in which validation failures are expressed

    ###### Parameters

    - `aDefaultValidationFailureHighlightMode`: the defaultValidationFailureHighlightMode to set

  - ### getDefaultValidationFailedEmblem

    public static Image getDefaultValidationFailedEmblem()

    The emblem that will be drawn on top of the component to indicate the validation failure

    ###### Returns

    the defaultValidationFailedEmblem

  - ### setDefaultValidationFailedEmblem

    public static void setDefaultValidationFailedEmblem(Image aDefaultValidationFailedEmblem)

    The emblem that will be drawn on top of the component to indicate the validation failure

    ###### Parameters

    - `aDefaultValidationFailedEmblem`: the defaultValidationFailedEmblem to set

  - ### getDefaultValidationEmblemPositionX

    public static float getDefaultValidationEmblemPositionX()

    The position of the validation emblem on the component as X/Y values between 0 and 1 where 0 indicates the start of the component and 1 indicates its end on the given axis.

    ###### Returns

    the defaultValidationEmblemPositionX

  - ### setDefaultValidationEmblemPositionX

    public static void setDefaultValidationEmblemPositionX(float aDefaultValidationEmblemPositionX)

    The position of the validation emblem on the component as X/Y values between 0 and 1 where 0 indicates the start of the component and 1 indicates its end on the given axis.

    ###### Parameters

    - `aDefaultValidationEmblemPositionX`: the defaultValidationEmblemPositionX to set

  - ### getDefaultValidationEmblemPositionY

    public static float getDefaultValidationEmblemPositionY()

    The position of the validation emblem on the component as X/Y values between 0 and 1 where 0 indicates the start of the component and 1 indicates its end on the given axis.

    ###### Returns

    the defaultValidationEmblemPositionY

  - ### setDefaultValidationEmblemPositionY

    public static void setDefaultValidationEmblemPositionY(float aDefaultValidationEmblemPositionY)

    The position of the validation emblem on the component as X/Y values between 0 and 1 where 0 indicates the start of the component and 1 indicates its end on the given axis.

    ###### Parameters

    - `aDefaultValidationEmblemPositionY`: the defaultValidationEmblemPositionY to set

  - ### isValidateOnEveryKey

    public static boolean isValidateOnEveryKey()

    Indicates whether validation should occur on every key press (data change listener) or action performed (editing completion)

    ###### Returns

    the validateOnEveryKey

  - ### setValidateOnEveryKey

    public static void setValidateOnEveryKey(boolean aValidateOnEveryKey)

    Indicates whether validation should occur on every key press (data change listener) or action performed (editing completion)

    ###### Parameters

    - `aValidateOnEveryKey`: the validateOnEveryKey to set

  - ### getValidationFailureHighlightMode

    public Validator.HighlightMode getValidationFailureHighlightMode()

    Indicates the default mode in which validation failures are expressed

    ###### Returns

    the validationFailureHighlightMode

  - ### setValidationFailureHighlightMode

    public void setValidationFailureHighlightMode(Validator.HighlightMode validationFailureHighlightMode)

    Indicates the default mode in which validation failures are expressed

    ###### Parameters

    - `validationFailureHighlightMode`: the validationFailureHighlightMode to set

  - ### getValidationFailedEmblem

    public Image getValidationFailedEmblem()

    The emblem that will be drawn on top of the component to indicate the validation failure

    ###### Returns

    the validationFailedEmblem

  - ### setValidationFailedEmblem

    public void setValidationFailedEmblem(Image validationFailedEmblem)

    The emblem that will be drawn on top of the component to indicate the validation failure

    ###### Parameters

    - `validationFailedEmblem`: the validationFailedEmblem to set

  - ### getValidationEmblemPositionX

    public float getValidationEmblemPositionX()

    The position of the validation emblem on the component as X/Y values between 0 and 1 where 0 indicates the start of the component and 1 indicates its end on the given axis.

    ###### Returns

    the validationEmblemPositionX

  - ### setValidationEmblemPositionX

    public void setValidationEmblemPositionX(float validationEmblemPositionX)

    The position of the validation emblem on the component as X/Y values between 0 and 1 where 0 indicates the start of the component and 1 indicates its end on the given axis.

    ###### Parameters

    - `validationEmblemPositionX`: the validationEmblemPositionX to set

  - ### getValidationEmblemPositionY

    public float getValidationEmblemPositionY()

    The position of the validation emblem on the component as X/Y values between 0 and 1 where 0 indicates the start of the component and 1 indicates its end on the given axis.

    ###### Returns

    the validationEmblemPositionY

  - ### setValidationEmblemPositionY

    public void setValidationEmblemPositionY(float validationEmblemPositionY)

    The position of the validation emblem on the component as X/Y values between 0 and 1 where 0 indicates the start of the component and 1 indicates its end on the given axis.

    ###### Parameters

    - `validationEmblemPositionY`: the validationEmblemPositionY to set

  - ### isShowErrorMessageForFocusedComponent

    public boolean isShowErrorMessageForFocusedComponent()

    Indicates whether an error message should be shown for the focused component

    ###### Returns

    true if the error message should be displayed

  - ### setShowErrorMessageForFocusedComponent

    public void setShowErrorMessageForFocusedComponent(boolean showErrorMessageForFocusedComponent)

    Indicates whether an error message should be shown for the focused component

    ###### Parameters

    - `showErrorMessageForFocusedComponent`: true to show the error message

  - ### getErrorMessageUIID

    public String getErrorMessageUIID()

    Error message UIID defaults to DialogBody. Allows customizing the look of the message

    ###### Returns

    the errorMessageUIID

  - ### setErrorMessageUIID

    public void setErrorMessageUIID(String errorMessageUIID)

    Error message UIID defaults to DialogBody. Allows customizing the look of the message

    ###### Parameters

    - `errorMessageUIID`: the errorMessageUIID to set

  - ### addConstraint

    public Validator addConstraint(Component cmp, Constraint... c)

    Places a constraint on the validator, returns this object so constraint additions can be chained. Shows validation errors messages even when the TextModeLayout is not `onTopMode` (it's possible to disable this functionality setting to false the theme constant `showValidationErrorsIfNotOnTopMode`: basically, the error message is shown for two second in place of the label on the left of the InputComponent (or on right of the InputComponent for RTL languages); this solution never breaks the layout, because the error message is trimmed to fit the available space. The error message UIID is "ErrorLabel" when it's not onTopMode.

    ###### Parameters

    - `cmp`: the component to validate

    - `c`: the constraint or constraints

    ###### Returns

    Returns:
      this object so we can write code like v.addConstraint(cmp1, cons).addConstraint(cmp2, otherConstraint);

  - ### addSubmitButtons

    public Validator addSubmitButtons(Component... cmp)

    Submit buttons (or any other component type) can be disabled until all components contain a valid value. Notice that this method should be invoked after all the constraints are added so the initial state of the buttons will be correct.

    ###### Parameters

    - `cmp`: set of buttons or components to disable until everything is valid

    ###### Returns

    the validator instance so this method can be chained

  - ### getComponentValue

    protected Object getComponentValue(Component cmp)

    Returns the value of the given component, this can be overriden to add support for custom built components

    ###### Parameters

    - `cmp`: the component

    ###### Returns

    the object value

  - ### bindDataListener

    public void bindDataListener(Component cmp)

    Binds an event listener to the given component

    ###### Parameters

    - `cmp`: the component to bind the data listener to

    ###### Deprecated

  - ### isValid

    public boolean isValid()

    Returns true if all the constraints are currently valid

    ###### Returns

    true if the entire validator is valid

  - ### validate

    protected void validate(Component cmp)

    Validates and highlights an individual component

    ###### Parameters

    - `cmp`: the component to validate

  - ### getErrorMessage

    public String getErrorMessage(Component cmp)

    Returns the validation error message for the given component or null if no such message exists

    ###### Parameters

    - `cmp`: the invalid component

    ###### Returns

    a string representing the error message