com.vaadin.flow.component.customfield

Class CustomField<T>

java.lang.Object

com.vaadin.flow.component.Component

com.vaadin.flow.component.AbstractField<CustomField<T>,T>

com.vaadin.flow.component.customfield.CustomField<T>

Type Parameters:

T - field value type

All Implemented Interfaces:

AttachNotifier, BlurNotifier<CustomField>, DetachNotifier, Focusable<CustomField>, FocusNotifier<CustomField>, HasElement, HasEnabled, HasSize, HasValidation, HasValue<AbstractField.ComponentValueChangeEvent<CustomField<T>,T>,T>, HasValueAndElement<AbstractField.ComponentValueChangeEvent<CustomField<T>,T>,T>, Serializable

@Tag(value="vaadin-custom-field")
 @HtmlImport(value="frontend://bower_components/vaadin-custom-field/src/vaadin-custom-field.html")
public abstract class CustomField<T>
extends AbstractField<CustomField<T>,T>
implements HasSize, HasValidation, Focusable<CustomField>

A HasValue whose UI content can be constructed by the user, enabling the creation of e.g. form fields by composing Vaadin components. Customization of both the visual presentation and the logic of the field is possible.

Subclasses must implement generateModelValue() and AbstractFieldsetPresentationValue(Object).

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class com.vaadin.flow.component.AbstractField

AbstractField.ComponentValueChangeEvent<C extends Component,V>

Nested classes/interfaces inherited from interface com.vaadin.flow.component.BlurNotifier

BlurNotifier.BlurEvent<C extends Component>

Nested classes/interfaces inherited from interface com.vaadin.flow.component.FocusNotifier

FocusNotifier.FocusEvent<C extends Component>

Nested classes/interfaces inherited from interface com.vaadin.flow.component.HasValue

HasValue.ValueChangeEvent<V>, HasValue.ValueChangeListener<E extends HasValue.ValueChangeEvent<?>>

Constructor Summary

Constructors

Constructor and Description
CustomField() Default constructor.
CustomField(T defaultValue) Constructs a new custom field.

Method Summary

Modifier and Type	Method and Description
protected void	add(Component... components) Adds the given components as children of this component.
protected abstract T	generateModelValue() This method should return the value of the field, based on value of the internal fields.
String	getErrorMessage() Gets current error message from the component.
String	getLabel() Gets the label for the field.
boolean	isInvalid() This property is set to true when the control value is invalid.
protected void	remove(Component... components) Removes the given child components from this component.
void	setErrorMessage(String errorMessage) Sets an error message to the component.
void	setInvalid(boolean invalid) This property is set to true when the control value is invalid.
void	setLabel(String label) Sets the label for the field.
protected abstract void	setPresentationValue(T newPresentationValue) This method should be implemented to set the value of the fields contained in this custom field according to the value of the parameter.
protected void	updateValue() Regenerates the value by calling generateModelValue() and updates the model.

Methods inherited from class com.vaadin.flow.component.AbstractField

addValueChangeListener, getEmptyValue, getValue, isEmpty, setModelValue, setValue, valueEquals

Methods inherited from class com.vaadin.flow.component.Component

addListener, fireEvent, from, get, getChildren, getElement, getEventBus, getId, getLocale, getParent, getTranslation, getTranslation, getUI, hasListener, isTemplateMapped, isVisible, onAttach, onDetach, onEnabledStateChanged, set, setElement, setId, setVisible

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.vaadin.flow.component.HasSize

getHeight, getMaxHeight, getMaxWidth, getMinHeight, getMinWidth, getWidth, setHeight, setHeightFull, setMaxHeight, setMaxWidth, setMinHeight, setMinWidth, setSizeFull, setSizeUndefined, setWidth, setWidthFull

Methods inherited from interface com.vaadin.flow.component.Focusable

addFocusShortcut, blur, focus, getTabIndex, setTabIndex

Methods inherited from interface com.vaadin.flow.component.BlurNotifier

addBlurListener

Methods inherited from interface com.vaadin.flow.component.FocusNotifier

addFocusListener

Methods inherited from interface com.vaadin.flow.component.HasEnabled

isEnabled, setEnabled

Methods inherited from interface com.vaadin.flow.component.HasElement

getElement

Methods inherited from interface com.vaadin.flow.component.HasValueAndElement

isReadOnly, isRequiredIndicatorVisible, setReadOnly, setRequiredIndicatorVisible

Methods inherited from interface com.vaadin.flow.component.HasValue

clear, getOptionalValue

Methods inherited from interface com.vaadin.flow.component.AttachNotifier

addAttachListener

Methods inherited from interface com.vaadin.flow.component.DetachNotifier

addDetachListener

Constructor Detail

CustomField

public CustomField()

Default constructor.

CustomField

public CustomField(T defaultValue)

Constructs a new custom field.

Parameters:

defaultValue - The initial value for the field. Will also be used by AbstractField.getEmptyValue().

See Also:

AbstractField.AbstractField(Object)

Method Detail

generateModelValue

protected abstract T generateModelValue()

This method should return the value of the field, based on value of the internal fields.

Returns:

new value of the field.

setPresentationValue

protected abstract void setPresentationValue(T newPresentationValue)

This method should be implemented to set the value of the fields contained in this custom field according to the value of the parameter. It can also be use to show the value to the user in some way, like placing it in an element contained on the field.

Updates the presentation of this field to display the provided value. Subclasses should override this method to show the value to the user. This is typically done by setting an element property or by applying changes to child components.

If AbstractField.setModelValue(Object, boolean) is called from within this method, the value of the last invocation will be used as the model value instead of the value passed to this method. In this case AbstractField.setPresentationValue(Object) will not be called again. Changing the provided value might be useful if the provided value is sanitized.

See AbstractField for an overall description on the difference between model values and presentation values.

Specified by:

setPresentationValue in class AbstractField<CustomField<T>,T>

Parameters:

newPresentationValue - The new presentation value.

updateValue

protected void updateValue()

Regenerates the value by calling generateModelValue() and updates the model. If the value is different than the current one, a ValueChangeEvent will be generated with ValueChangeEvent#isFromClient() set to true

This method is called when the webcomponent generates a changed event, typically in response to a change made by the user in one of the contained fields.

Custom implementations of this method must call AbstractField.setModelValue(Object, boolean) with the updated model value. Subclasses can call this method when the model value needs to be regenerated and updated.

add

protected void add(Component... components)

Adds the given components as children of this component.

Parameters:

components - the components to add

remove

protected void remove(Component... components)

Removes the given child components from this component.

Parameters:

components - the components to remove

Throws:

IllegalArgumentException - if any of the components is not a child of this component

isInvalid

@Synchronize(property="invalid",
             value="invalid-changed")
public boolean isInvalid()

This property is set to true when the control value is invalid.

This property is synchronized automatically from client side when a 'invalid-changed' event happens.

Specified by:

isInvalid in interface HasValidation

Returns:

the invalid property from the webcomponent

setInvalid

public void setInvalid(boolean invalid)

This property is set to true when the control value is invalid.

Specified by:

setInvalid in interface HasValidation

Parameters:

invalid - the boolean value to set

setErrorMessage

public void setErrorMessage(String errorMessage)

Description copied from interface: HasValidation

Sets an error message to the component.

The Web Component is responsible for deciding when to show the error message to the user, and this is usually triggered by triggering the invalid state for the Web Component. Which means that there is no need to clean up the message when component becomes valid (otherwise it may lead to undesired visual effects).

Specified by:

setErrorMessage in interface HasValidation

Parameters:

errorMessage - a new error message

getErrorMessage

public String getErrorMessage()

Description copied from interface: HasValidation

Gets current error message from the component.

Specified by:

getErrorMessage in interface HasValidation

Returns:

current error message

getLabel

public String getLabel()

Gets the label for the field.

Returns:

the label property from the webcomponent

setLabel

public void setLabel(String label)

Sets the label for the field.

Parameters:

label - value for the label property in the webcomponent