Package com.vaadin.flow.component.checkbox

Class CheckboxGroup<T>

java.lang.Object

com.vaadin.flow.component.Component

com.vaadin.flow.component.AbstractField<CheckboxGroup<T>,Set<T>>

com.vaadin.flow.component.AbstractSinglePropertyField<CheckboxGroup<T>,Set<T>>

com.vaadin.flow.component.checkbox.CheckboxGroup<T>

All Implemented Interfaces:

AttachNotifier, DetachNotifier, HasAriaLabel, HasComponents, HasElement, HasEnabled, HasHelper, HasLabel, HasSize, HasStyle, HasTheme, HasValidation, HasValue<AbstractField.ComponentValueChangeEvent<CheckboxGroup<T>,Set<T>>,Set<T>>, HasValueAndElement<AbstractField.ComponentValueChangeEvent<CheckboxGroup<T>,Set<T>>,Set<T>>, HasThemeVariant<CheckboxGroupVariant>, HasTooltip, HasValidationProperties, InputField<AbstractField.ComponentValueChangeEvent<CheckboxGroup<T>,Set<T>>,Set<T>>, HasItemComponents<T>, HasValidator<Set<T>>, HasDataView<T,Void,CheckboxGroupDataView<T>>, HasListDataView<T,CheckboxGroupListDataView<T>>, MultiSelect<CheckboxGroup<T>,T>, Serializable

@Tag("vaadin-checkbox-group")
@NpmPackage(value="@vaadin/checkbox-group",
            version="25.0.0-beta1")
@JsModule("@vaadin/checkbox-group/src/vaadin-checkbox-group.js")
public class CheckboxGroup<T>
extends AbstractSinglePropertyField<CheckboxGroup<T>,Set<T>>
implements HasAriaLabel, HasDataView<T,Void,CheckboxGroupDataView<T>>, HasItemComponents<T>, InputField<AbstractField.ComponentValueChangeEvent<CheckboxGroup<T>,Set<T>>,Set<T>>, HasListDataView<T,CheckboxGroupListDataView<T>>, HasThemeVariant<CheckboxGroupVariant>, HasValidationProperties, HasValidator<Set<T>>, MultiSelect<CheckboxGroup<T>,T>

CheckBoxGroup is a multi-selection component where items are displayed as check boxes.

Use CheckBoxGroup to group related items. Individual checkboxes should be used for options that are not related to each other in any way.

Validation

CheckboxGroup comes with a built-in validation mechanism that verifies that at least one checkbox is selected when required is enabled.

Validation is triggered whenever the user initiates a value change by toggling a checkbox. Programmatic value changes trigger validation as well. If validation fails, the component is marked as invalid and an error message is displayed below the group.

The required error message can be configured using either CheckboxGroup.CheckboxGroupI18n.setRequiredErrorMessage(String) or HasValidationProperties.setErrorMessage(String).

For more advanced validation that requires custom rules, you can use Binder. Please note that Binder provides its own API for the required validation, see asRequired().

However, if Binder doesn't fit your needs and you want to implement fully custom validation logic, you can disable the built-in validation by setting setManualValidation(boolean) to true. This will allow you to control the invalid state and the error message manually using HasValidationProperties.setInvalid(boolean) and HasValidationProperties.setErrorMessage(String) API.

Author:

Vaadin Ltd

See Also:

• Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	CheckboxGroup.CheckboxGroupI18n	The internationalization properties for CheckboxGroup.
static interface	CheckboxGroup.ItemHelperGenerator<T>	CheckboxGroup.ItemHelperGenerator can be used to generate helper text strings used by the checkbox group for each checkbox.

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.data.binder.HasItemComponents

HasItemComponents.ItemComponent<T>

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

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

Constructor Summary

Constructors

Constructor	Description
CheckboxGroup()	Creates an empty checkbox group
CheckboxGroup(HasValue.ValueChangeListener<AbstractField.ComponentValueChangeEvent<CheckboxGroup<T>,Set<T>>> listener)	Constructs a checkbox group with a value change listener.
CheckboxGroup(String label)	Creates an empty checkbox group with the defined label.
CheckboxGroup(String label, HasValue.ValueChangeListener<AbstractField.ComponentValueChangeEvent<CheckboxGroup<T>,Set<T>>> listener)	Constructs a checkbox group with the defined label and a value change listener.
CheckboxGroup(String label, HasValue.ValueChangeListener<AbstractField.ComponentValueChangeEvent<CheckboxGroup<T>,Set<T>>> listener, T... items)	Constructs a checkbox group with the defined label, a value change listener and populated with the items in the array.
CheckboxGroup(String label, Collection<T> items)	Creates a checkbox group with the defined label and populated with the items in the collection.
CheckboxGroup(String label, T... items)	Creates a checkbox group with the defined label and populated with the items in the array.

Method Summary

Modifier and Type	Method	Description
Registration	addSelectionListener(MultiSelectionListener<CheckboxGroup<T>,T> listener)	Adds a selection listener that will be called when the selection is changed either by the user or programmatically.
Optional<String>	getAriaLabel()	Gets the aria-label of the component.
Optional<String>	getAriaLabelledBy()	Gets the aria-labelledby of the component
DataProvider<T,?>	getDataProvider()	Gets the data provider used by this CheckboxGroup.
Validator<Set<T>>	getDefaultValidator()	Returns a validator that checks the state of the Value.
CheckboxGroupDataView<T>	getGenericDataView()	Gets the generic data view for the checkbox group.
CheckboxGroup.CheckboxGroupI18n	getI18n()	Gets the internationalization object previously set for this component.
SerializablePredicate<T>	getItemEnabledProvider()	Returns the item enabled predicate.
CheckboxGroup.ItemHelperGenerator<T>	getItemHelperGenerator()	Gets the CheckboxGroup.ItemHelperGenerator function that is used for generating helper text strings used by the checkbox group for each item.
ItemLabelGenerator<T>	getItemLabelGenerator()	Gets the item label generator that is used to produce the strings shown in the checkbox group for each item.
ComponentRenderer<? extends Component,T>	getItemRenderer()	Returns the item component renderer.
String	getLabel()	Gets the label of the checkbox group.
CheckboxGroupListDataView<T>	getListDataView()	Gets the list data view for the checkbox group.
Set<T>	getSelectedItems()	Returns an immutable set of the currently selected items.
SelectionPreservationMode	getSelectionPreservationMode()	Gets the selection preservation mode.
protected boolean	hasValidValue()	Checks whether the element property has a value that can be converted to the model type.
protected boolean	isDisabledBoolean()	If true, the user cannot interact with this element.
boolean	isRequired()	Alias for isRequiredIndicatorVisible()
boolean	isRequiredIndicatorVisible()	Gets whether the user is required to select at least one checkbox.
void	onEnabledStateChanged(boolean enabled)	Handle component enable state when the enabled state changes.
void	setAriaLabel(String ariaLabel)	Set the aria-label of the component to the given text.
void	setAriaLabelledBy(String labelledBy)	Set the aria-labelledby of the component.
void	setDataProvider(DataProvider<T,?> dataProvider)	Sets a generic data provider for the CheckboxGroup to use.
protected void	setDisabled(boolean disabled)	If true, the user cannot interact with this element.
void	setI18n(CheckboxGroup.CheckboxGroupI18n i18n)	Sets the internationalization object for this component.
void	setItemEnabledProvider(SerializablePredicate<T> itemEnabledProvider)	Sets the item enabled predicate for this checkbox group.
void	setItemHelperGenerator(CheckboxGroup.ItemHelperGenerator<T> itemHelperGenerator)	Sets the CheckboxGroup.ItemHelperGenerator that is used for generating helper text strings used by the checkbox group for each item.
void	setItemLabelGenerator(ItemLabelGenerator<T> itemLabelGenerator)	Sets the item label generator that is used to produce the strings shown in the checkbox group for each item.
CheckboxGroupDataView<T>	setItems(DataProvider<T,Void> dataProvider)	Set a generic data provider for the component to use and returns the base DataView that provides API to get information on the items.
CheckboxGroupDataView<T>	setItems(InMemoryDataProvider<T> inMemoryDataProvider)	Sets an in-memory data provider for the component to use
CheckboxGroupListDataView<T>	setItems(ListDataProvider<T> dataProvider)	Sets a ListDataProvider for the component to use and returns a ListDataView that provides information and allows operations on the items.
void	setLabel(String label)	Sets the label for the checkbox group.
void	setManualValidation(boolean enabled)	Sets whether manual validation mode is enabled for the component.
void	setRenderer(ComponentRenderer<? extends Component,T> renderer)	Sets the item renderer for this checkbox group.
void	setRequired(boolean required)	Alias for setRequiredIndicatorVisible(boolean).
void	setRequiredIndicatorVisible(boolean required)	Sets whether the user is required to select at least one checkbox.
void	setSelectionPreservationMode(SelectionPreservationMode selectionPreservationMode)	Sets the selection preservation mode.
void	setValue(Set<T> value)	Sets the value of this component.
void	updateSelection(Set<T> addedItems, Set<T> removedItems)	Updates the selection by adding and removing the given items from it.
protected void	validate()	Validates the current value against the constraints and sets the invalid property and the errorMessage property based on the result.
protected boolean	valueEquals(Set<T> value1, Set<T> value2)	Compares to value instances to each other to determine whether they are equal.

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

getSynchronizationRegistration, setPresentationValue, setSynchronizedEvent

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

addValueChangeListener, getEmptyValue, getValue, isEmpty, setModelValue

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

addListener, findAncestor, fireEvent, from, get, getChildren, getElement, getEventBus, getId, getListeners, getLocale, getParent, getTranslation, getTranslation, getTranslation, getTranslation, getTranslation, getTranslation, getUI, hasListener, isAttached, isTemplateMapped, isVisible, onAttach, onDetach, removeFromParent, scrollIntoView, scrollIntoView, 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.AttachNotifier

addAttachListener

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

addDetachListener

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

add, add, add, addComponentAsFirst, addComponentAtIndex, remove, remove, removeAll

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

getElement

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

isEnabled, setEnabled

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

getHelperComponent, getHelperText, setHelperComponent, setHelperText

Methods inherited from interface com.vaadin.flow.data.binder.HasItemComponents

addComponents, getItemPosition, prependComponents

Methods inherited from interface com.vaadin.flow.data.provider.HasListDataView

setItems, setItems

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

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

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

addClassName, addClassNames, getClassName, getClassNames, getStyle, hasClassName, removeClassName, removeClassNames, setClassName, setClassName

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

addThemeName, addThemeNames, getThemeName, getThemeNames, hasThemeName, removeThemeName, removeThemeNames, setThemeName, setThemeName

Methods inherited from interface com.vaadin.flow.component.shared.HasThemeVariant

addThemeVariants, removeThemeVariants, setThemeVariant, setThemeVariants, setThemeVariants

Methods inherited from interface com.vaadin.flow.component.shared.HasTooltip

getTooltip, setTooltipMarkdown, setTooltipText

Methods inherited from interface com.vaadin.flow.component.shared.HasValidationProperties

getErrorMessage, isInvalid, setErrorMessage, setInvalid

Methods inherited from interface com.vaadin.flow.data.binder.HasValidator

addValidationStatusChangeListener

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

addValueChangeListener, clear, getOptionalValue, isEmpty

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

isReadOnly, setReadOnly

Methods inherited from interface com.vaadin.flow.data.selection.MultiSelect

deselect, deselect, deselectAll, getEmptyValue, getValue, isSelected, select, select

Constructor Details

CheckboxGroup

public CheckboxGroup()

Creates an empty checkbox group

CheckboxGroup

public CheckboxGroup(String label)

Creates an empty checkbox group with the defined label.

Parameters:

label - the label describing the checkbox group

See Also:

• setLabel(String)

CheckboxGroup

public CheckboxGroup(String label,
 Collection<T> items)

Creates a checkbox group with the defined label and populated with the items in the collection.

Parameters:

label - the label describing the checkbox group

items - the items to be shown in the list of the checkbox group

See Also:

• setLabel(String)
• HasListDataView.setItems(Collection)

CheckboxGroup

@SafeVarargs
public CheckboxGroup(String label,
 T... items)

Creates a checkbox group with the defined label and populated with the items in the array.

Parameters:

label - the label describing the checkbox group

items - the items to be shown in the list of the checkbox group

See Also:

• setLabel(String)
• HasListDataView.setItems(Object...)

CheckboxGroup

public CheckboxGroup(HasValue.ValueChangeListener<AbstractField.ComponentValueChangeEvent<CheckboxGroup<T>,Set<T>>> listener)

Constructs a checkbox group with a value change listener.

Parameters:

listener - the value change listener to add

See Also:

• AbstractField.addValueChangeListener(ValueChangeListener)

CheckboxGroup

public CheckboxGroup(String label,
 HasValue.ValueChangeListener<AbstractField.ComponentValueChangeEvent<CheckboxGroup<T>,Set<T>>> listener)

Constructs a checkbox group with the defined label and a value change listener.

Parameters:

label - the label describing the checkbox group

listener - the value change listener to add

See Also:

• setLabel(String)
• AbstractField.addValueChangeListener(ValueChangeListener)

CheckboxGroup

@SafeVarargs
public CheckboxGroup(String label,
 HasValue.ValueChangeListener<AbstractField.ComponentValueChangeEvent<CheckboxGroup<T>,Set<T>>> listener,
 T... items)

Constructs a checkbox group with the defined label, a value change listener and populated with the items in the array.

Parameters:

label - the label describing the checkbox group

listener - the value change listener to add

items - the items to be shown in the list of the checkbox group

See Also:

• setLabel(String)
• AbstractField.addValueChangeListener(ValueChangeListener)
• HasListDataView.setItems(Object...)

Method Details

setItems

public CheckboxGroupDataView<T> setItems(DataProvider<T,Void> dataProvider)

Description copied from interface: HasDataView

Set a generic data provider for the component to use and returns the base DataView that provides API to get information on the items.

This method should be used only when the data provider type is not either ListDataProvider or BackEndDataProvider.

Specified by:

setItems in interface HasDataView<T,Void,CheckboxGroupDataView<T>>

Parameters:

dataProvider - DataProvider instance to use, not null

Returns:

DataView providing information on the data

setItems

public CheckboxGroupDataView<T> setItems(InMemoryDataProvider<T> inMemoryDataProvider)

Description copied from interface: HasDataView

Sets an in-memory data provider for the component to use

Note! Using a ListDataProvider instead of a InMemoryDataProvider is recommended to get access to ListDataView API by using HasListDataView.setItems(ListDataProvider).

Specified by:

setItems in interface HasDataView<T,Void,CheckboxGroupDataView<T>>

Parameters:

inMemoryDataProvider - InMemoryDataProvider to use, not null

Returns:

DataView providing information on the data

setItems

public CheckboxGroupListDataView<T> setItems(ListDataProvider<T> dataProvider)

Description copied from interface: HasListDataView

Sets a ListDataProvider for the component to use and returns a ListDataView that provides information and allows operations on the items.

Specified by:

setItems in interface HasListDataView<T,CheckboxGroupListDataView<T>>

Parameters:

dataProvider - ListDataProvider providing items to the component.

Returns:

ListDataView providing access to the items

getListDataView

public CheckboxGroupListDataView<T> getListDataView()

Gets the list data view for the checkbox group. This data view should only be used when the items are in-memory and set with:

• HasListDataView.setItems(Collection)
• HasListDataView.setItems(Object[])
• setItems(ListDataProvider)

If the items are not in-memory an exception is thrown.

Specified by:

getListDataView in interface HasListDataView<T,CheckboxGroupListDataView<T>>

Returns:

the list data view that provides access to the data bound to the checkbox group

getGenericDataView

public CheckboxGroupDataView<T> getGenericDataView()

Gets the generic data view for the checkbox group. This data view should only be used when getListDataView() is not applicable for the underlying data provider.

Specified by:

getGenericDataView in interface HasDataView<T,Void,CheckboxGroupDataView<T>>

Returns:

the generic DataView instance implementing CheckboxGroupDataView

setDataProvider

public void setDataProvider(DataProvider<T,?> dataProvider)

Sets a generic data provider for the CheckboxGroup to use.

Use this method when none of the setItems methods are applicable, e.g. when having a data provider with filter that cannot be transformed to DataProvider<T, Void>.

Parameters:

dataProvider - DataProvider instance to use, not null

updateSelection

public void updateSelection(Set<T> addedItems,
 Set<T> removedItems)

Description copied from interface: MultiSelect

Updates the selection by adding and removing the given items from it.

If all the added items were already selected and the removed items were not selected, this is a NO-OP.

Duplicate items (in both add and remove sets) are ignored.

Specified by:

updateSelection in interface MultiSelect<CheckboxGroup<T>,T>

Parameters:

addedItems - the items to add, not null

removedItems - the items to remove, not null

setValue

public void setValue(Set<T> value)

Sets the value of this component. If the new value is not equal to the previous value, fires a value change event.

The component doesn't accept null values. The value of a checkbox group without any selected items is an empty set. You can use the HasValue.clear() method to set the empty value.

Specified by:

setValue in interface HasValue<AbstractField.ComponentValueChangeEvent<CheckboxGroup<T>,Set<T>>,Set<T>>

Specified by:

setValue in interface MultiSelect<CheckboxGroup<T>,T>

Overrides:

setValue in class AbstractField<CheckboxGroup<T>,Set<T>>

Parameters:

value - the new value to set, not null

Throws:

NullPointerException - if value is null

getSelectedItems

public Set<T> getSelectedItems()

Description copied from interface: MultiSelect

Returns an immutable set of the currently selected items. It is safe to invoke other SelectionModel methods while iterating over the set.

Implementation note: the iteration order of the items in the returned set should be well-defined and documented by the implementing class.

Specified by:

getSelectedItems in interface MultiSelect<CheckboxGroup<T>,T>

Returns:

the items in the current selection, not null

addSelectionListener

public Registration addSelectionListener(MultiSelectionListener<CheckboxGroup<T>,T> listener)

Description copied from interface: MultiSelect

Adds a selection listener that will be called when the selection is changed either by the user or programmatically.

Specified by:

addSelectionListener in interface MultiSelect<CheckboxGroup<T>,T>

Parameters:

listener - the value change listener, not null

Returns:

a registration for the listener

getDataProvider

public DataProvider<T,?> getDataProvider()

Gets the data provider used by this CheckboxGroup.

To get information and control over the items in the CheckboxGroup, use either getListDataView() or getGenericDataView() instead.

Returns:

the data provider used by this CheckboxGroup

onEnabledStateChanged

public void onEnabledStateChanged(boolean enabled)

Description copied from class: Component

Handle component enable state when the enabled state changes.

By default this sets or removes the 'disabled' attribute from the element. This can be overridden to have custom handling.

Overrides:

onEnabledStateChanged in class Component

Parameters:

enabled - the new enabled state of the component

getItemEnabledProvider

public SerializablePredicate<T> getItemEnabledProvider()

Returns the item enabled predicate.

Returns:

the item enabled predicate

See Also:

• setItemEnabledProvider(com.vaadin.flow.function.SerializablePredicate<T>)

setItemEnabledProvider

public void setItemEnabledProvider(SerializablePredicate<T> itemEnabledProvider)

Sets the item enabled predicate for this checkbox group. The predicate is applied to each item to determine whether the item should be enabled (true) or disabled (false). Disabled items are displayed as grayed out and the user cannot select them. The default predicate always returns true (all the items are enabled).

Parameters:

itemEnabledProvider - the item enable predicate, not null

setItemLabelGenerator

public void setItemLabelGenerator(ItemLabelGenerator<T> itemLabelGenerator)

Sets the item label generator that is used to produce the strings shown in the checkbox group for each item. By default, String.valueOf(Object) is used.

Setting an item label generator removes any previously set item renderer.

Parameters:

itemLabelGenerator - the item label provider to use, not null

getItemLabelGenerator

public ItemLabelGenerator<T> getItemLabelGenerator()

Gets the item label generator that is used to produce the strings shown in the checkbox group for each item.

Returns:

the item label generator used, not null

setItemHelperGenerator

public void setItemHelperGenerator(CheckboxGroup.ItemHelperGenerator<T> itemHelperGenerator)

Sets the CheckboxGroup.ItemHelperGenerator that is used for generating helper text strings used by the checkbox group for each item.

Parameters:

itemHelperGenerator - the item helper generator to use, not null

Since:

24.4

See Also:

• HasHelper.setHelperText(String)
• setItemLabelGenerator(com.vaadin.flow.component.ItemLabelGenerator<T>)

getItemHelperGenerator

public CheckboxGroup.ItemHelperGenerator<T> getItemHelperGenerator()

Gets the CheckboxGroup.ItemHelperGenerator function that is used for generating helper text strings used by the checkbox group for each item.

Returns:

the item helper generator, not null

Since:

24.4

See Also:

• getItemLabelGenerator()

setLabel

public void setLabel(String label)

Sets the label for the checkbox group.

Specified by:

setLabel in interface HasLabel

Parameters:

label - value for the label property in the checkbox group

getLabel

public String getLabel()

Gets the label of the checkbox group.

Specified by:

getLabel in interface HasLabel

Returns:

the label property of the checkbox group

setAriaLabel

public void setAriaLabel(String ariaLabel)

Description copied from interface: HasAriaLabel

Set the aria-label of the component to the given text.

This method should not be used if HasAriaLabel.setAriaLabelledBy(String) is also used. If both attributes are present, aria-labelledby will take precedence over aria-label.

Specified by:

setAriaLabel in interface HasAriaLabel

Parameters:

ariaLabel - the aria-label text to set or null to clear

getAriaLabel

public Optional<String> getAriaLabel()

Description copied from interface: HasAriaLabel

Gets the aria-label of the component.

Specified by:

getAriaLabel in interface HasAriaLabel

Returns:

an optional aria-label of the component if no aria-label has been set

setAriaLabelledBy

public void setAriaLabelledBy(String labelledBy)

Description copied from interface: HasAriaLabel

Set the aria-labelledby of the component. The value must be a valid id attribute of another element that labels the component. The label element must be in the same DOM scope of the component, otherwise screen readers may fail to announce the label content properly.

This method should not be used if HasAriaLabel.setAriaLabel(String) is also used. If both attributes are present, aria-labelledby will take precedence over aria-label.

Specified by:

setAriaLabelledBy in interface HasAriaLabel

Parameters:

labelledBy - the string with the id of the element that will be used as label or null to clear

getAriaLabelledBy

public Optional<String> getAriaLabelledBy()

Description copied from interface: HasAriaLabel

Gets the aria-labelledby of the component

Specified by:

getAriaLabelledBy in interface HasAriaLabel

Returns:

an optional aria-labelledby of the component if no aria-labelledby has been set

setRequiredIndicatorVisible

public void setRequiredIndicatorVisible(boolean required)

Sets whether the user is required to select at least one checkbox. When required, an indicator appears next to the label and the field invalidates if all previously selected checkboxes are deselected.

NOTE: The required indicator is only visible when the field has a label, see setLabel(String).

Specified by:

setRequiredIndicatorVisible in interface HasValue<AbstractField.ComponentValueChangeEvent<CheckboxGroup<T>,Set<T>>,Set<T>>

Specified by:

setRequiredIndicatorVisible in interface HasValueAndElement<AbstractField.ComponentValueChangeEvent<CheckboxGroup<T>,Set<T>>,Set<T>>

Parameters:

required - true to make the field required, false otherwise

See Also:

• CheckboxGroup.CheckboxGroupI18n.setRequiredErrorMessage(String)

isRequiredIndicatorVisible

public boolean isRequiredIndicatorVisible()

Gets whether the user is required to select at least one checkbox.

Specified by:

isRequiredIndicatorVisible in interface HasValue<AbstractField.ComponentValueChangeEvent<CheckboxGroup<T>,Set<T>>,Set<T>>

Specified by:

isRequiredIndicatorVisible in interface HasValueAndElement<AbstractField.ComponentValueChangeEvent<CheckboxGroup<T>,Set<T>>,Set<T>>

Returns:

true if the field is required, false otherwise

See Also:

• setRequiredIndicatorVisible(boolean)

isRequired

public boolean isRequired()

Alias for isRequiredIndicatorVisible()

Returns:

true if the field is required, false otherwise

setRequired

public void setRequired(boolean required)

Alias for setRequiredIndicatorVisible(boolean).

Parameters:

required - true to make the field required, false otherwise

setDisabled

protected void setDisabled(boolean disabled)

If true, the user cannot interact with this element.

Parameters:

disabled - the boolean value to set

isDisabledBoolean

protected boolean isDisabledBoolean()

If true, the user cannot interact with this element.

Returns:

the disabled property from the webcomponent

valueEquals

protected boolean valueEquals(Set<T> value1,
 Set<T> value2)

Description copied from class: AbstractField

Compares to value instances to each other to determine whether they are equal. Equality is used to determine whether to update internal state and fire an event when AbstractField.setValue(Object) or AbstractField.setModelValue(Object, boolean) is called. Subclasses can override this method to define an alternative comparison method instead of Object.equals(Object).

Overrides:

valueEquals in class AbstractField<CheckboxGroup<T>,Set<T>>

Parameters:

value1 - the first instance

value2 - the second instance

Returns:

true if the instances are equal; otherwise false

hasValidValue

protected boolean hasValidValue()

Description copied from class: AbstractSinglePropertyField

Checks whether the element property has a value that can be converted to the model type. Property changes from the element will be ignored if this method returns false. The default implementation always return true.

Overrides:

hasValidValue in class AbstractSinglePropertyField<CheckboxGroup<T>,Set<T>>

Returns:

true if the element property value can be converted to the model type; otherwise false

getItemRenderer

public ComponentRenderer<? extends Component,T> getItemRenderer()

Returns the item component renderer.

Returns:

the item renderer

Since:

23.1

See Also:

• setRenderer(ComponentRenderer)

setRenderer

public void setRenderer(ComponentRenderer<? extends Component,T> renderer)

Sets the item renderer for this checkbox group. The renderer is applied to each item to create a component which represents the item.

Note: Component acts as a label to the checkbox and clicks on it trigger the checkbox. Hence interactive components like DatePicker or ComboBox cannot be used.

Parameters:

renderer - the item renderer, not null

Since:

23.1

setSelectionPreservationMode

public void setSelectionPreservationMode(SelectionPreservationMode selectionPreservationMode)

Sets the selection preservation mode. Determines what happens with the selection when DataProvider.refreshAll() is called. The selection is discarded in any case when a new data provider is set. The default is SelectionPreservationMode.DISCARD.

Parameters:

selectionPreservationMode - the selection preservation mode to switch to, not null

See Also:

• SelectionPreservationMode

getSelectionPreservationMode

public SelectionPreservationMode getSelectionPreservationMode()

Gets the selection preservation mode.

Returns:

the selection preservation mode

See Also:

• setSelectionPreservationMode(SelectionPreservationMode)

setManualValidation

public void setManualValidation(boolean enabled)

Description copied from interface: HasValidation

Sets whether manual validation mode is enabled for the component.

When enabled, the component doesn't perform its built-in constraint validation on value change, blur, and other events. This allows manually controlling the invalid state and error messages using the HasValidation.setInvalid(boolean) and HasValidation.setErrorMessage(String) methods. Manual mode is helpful when there is a need for a totally custom validation logic that cannot be achieved with Binder.

Example:

 Field field = new Field();
 field.setManualValidation(true);
 field.addValueChangeListener(event -> {
     if (Objects.equal(event.getValue(), "")) {
         field.setInvalid(true);
         field.setErrorMessage("The field is required.");
     } else {
         field.setInvalid(false);
     }
 });
 

For components that don't have built-in validation, the method has no effect.

Specified by:

setManualValidation in interface HasValidation

Parameters:

enabled - whether to enable manual validation mode.

getDefaultValidator

public Validator<Set<T>> getDefaultValidator()

Description copied from interface: HasValidator

Returns a validator that checks the state of the Value. This should be overridden for components with internal value conversion or validation, e.g. when the user is providing a string that has to be parsed into a date. An invalid input from user will be exposed to a Binder and can be seen as a validation failure.

Specified by:

getDefaultValidator in interface HasValidator<T>

Returns:

state validator

validate

protected void validate()

Validates the current value against the constraints and sets the invalid property and the errorMessage property based on the result. If a custom error message is provided with HasValidationProperties.setErrorMessage(String), it is used. Otherwise, the error message defined in the i18n object is used.

The method does nothing if the manual validation mode is enabled.

getI18n

public CheckboxGroup.CheckboxGroupI18n getI18n()

Gets the internationalization object previously set for this component.

NOTE: Updating the instance that is returned from this method will not update the component if not set again using setI18n(CheckboxGroupI18n)

Returns:

the i18n object or null if no i18n object has been set

setI18n

public void setI18n(CheckboxGroup.CheckboxGroupI18n i18n)

Sets the internationalization object for this component.

Parameters:

i18n - the i18n object, not null