Package com.storedobject.vaadin.util

Class BasicComboList<T>

java.lang.Object

com.vaadin.flow.component.Component

com.vaadin.flow.component.AbstractField<com.vaadin.flow.component.listbox.ListBox<T>,T>

com.vaadin.flow.component.AbstractSinglePropertyField<com.vaadin.flow.component.listbox.ListBox<T>,T>

com.vaadin.flow.component.listbox.ListBoxBase<com.vaadin.flow.component.listbox.ListBox<T>,T,T>

com.vaadin.flow.component.listbox.ListBox<T>

com.storedobject.vaadin.util.BasicComboList<T>

Type Parameters:

T - the type of items managed by this combo list

All Implemented Interfaces:

com.vaadin.flow.component.AttachNotifier, com.vaadin.flow.component.DetachNotifier, com.vaadin.flow.component.HasAriaLabel, com.vaadin.flow.component.HasComponents, com.vaadin.flow.component.HasElement, com.vaadin.flow.component.HasEnabled, com.vaadin.flow.component.HasSize, com.vaadin.flow.component.HasStyle, com.vaadin.flow.component.HasValue<com.vaadin.flow.component.AbstractField.ComponentValueChangeEvent<com.vaadin.flow.component.listbox.ListBox<T>,T>,T>, com.vaadin.flow.component.HasValueAndElement<com.vaadin.flow.component.AbstractField.ComponentValueChangeEvent<com.vaadin.flow.component.listbox.ListBox<T>,T>,T>, com.vaadin.flow.component.shared.HasTooltip, com.vaadin.flow.data.binder.HasItemComponents<T>, com.vaadin.flow.data.provider.HasDataView<T,Void,com.vaadin.flow.component.listbox.dataview.ListBoxDataView<T>>, com.vaadin.flow.data.provider.HasListDataView<T,com.vaadin.flow.component.listbox.dataview.ListBoxListDataView<T>>, com.vaadin.flow.data.selection.SingleSelect<com.vaadin.flow.component.listbox.ListBox<T>,T>, Serializable

public class BasicComboList<T>
extends com.vaadin.flow.component.listbox.ListBox<T>

A generic combo box component that extends the ListBox class. This class allows managing a collection of items and provides methods to access, manipulate, and retrieve item values and their corresponding indices.

Author:

Syam

See Also:

• Serialized Form

Nested Class Summary

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

com.vaadin.flow.component.AbstractField.ComponentValueChangeEvent<C extends com.vaadin.flow.component.Component,V>

Nested classes/interfaces inherited from interface com.vaadin.flow.data.binder.HasItemComponents

com.vaadin.flow.data.binder.HasItemComponents.ItemComponent<T>

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

com.vaadin.flow.component.HasValue.ValueChangeEvent<V>, com.vaadin.flow.component.HasValue.ValueChangeListener<E extends com.vaadin.flow.component.HasValue.ValueChangeEvent<?>>

Field Summary

Fields

Modifier and Type	Field	Description
protected List<T>	list	The list of items managed by the BasicComboList.

Constructor Summary

Constructors

Constructor	Description
BasicComboList(Collection<T> list)	Constructs a BasicComboList instance using the provided collection of items.
BasicComboList(T... list)	Constructs a BasicComboList instance with a variable number of elements.

Method Summary

Modifier and Type	Method	Description
T	getEmptyValue()	Returns the default empty value for the component.
int	getIndex()	Retrieves the index of the item currently selected or set as the value of the combo list.
int	getIndex(T item)	Returns the index of the specified item in the list.
T	getValue(int index)	Retrieves the value at the specified index from the combo list.
protected void	setFirstValue()	Sets the current value of the combo list to the first item in the list.
com.vaadin.flow.component.listbox.dataview.ListBoxListDataView<T>	setItems(Collection<T> items)	Sets the items for the combo list with the provided collection.

Methods inherited from class com.vaadin.flow.component.listbox.ListBox

valueEquals

Methods inherited from class com.vaadin.flow.component.listbox.ListBoxBase

getDataProvider, getGenericDataView, getItemEnabledProvider, getItemId, getItemLabelGenerator, getItemRenderer, getListDataView, onAttach, onDetach, onEnabledStateChanged, setDataProvider, setItemEnabledProvider, setItemLabelGenerator, setItems, setItems, setItems, setRenderer, setRequiredIndicatorVisible

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

getSynchronizationRegistration, hasValidValue, setPresentationValue, setSynchronizedEvent

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

addValueChangeListener, getValue, isEmpty, setModelValue, setValue

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, 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.HasAriaLabel

getAriaLabel, getAriaLabelledBy, setAriaLabel, setAriaLabelledBy

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.data.binder.HasItemComponents

addComponents, getItemPosition, prependComponents

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

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.shared.HasTooltip

getTooltip, setTooltipText

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

addValueChangeListener, clear, getOptionalValue, getValue, isEmpty, setValue

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

isReadOnly, isRequiredIndicatorVisible, setReadOnly, setRequiredIndicatorVisible

Field Details

list

protected List<T> list

The list of items managed by the BasicComboList. This list represents the currently available collection of items within the combo box, which can be manipulated or retrieved as needed.

Constructor Details

BasicComboList

@SafeVarargs
public BasicComboList(T... list)

Constructs a BasicComboList instance with a variable number of elements. Allows initializing the combo list with multiple items provided as arguments.

Parameters:

list - the elements to initialize the combo list with. These elements will be converted into a collection of items managed by this combo list.

BasicComboList

public BasicComboList(Collection<T> list)

Constructs a BasicComboList instance using the provided collection of items.

Parameters:

list - the collection of items to initialize the combo list; if null, an empty list will be used

Method Details

setItems

public com.vaadin.flow.component.listbox.dataview.ListBoxListDataView<T> setItems(Collection<T> items)

Sets the items for the combo list with the provided collection. If the input collection is null, an empty collection is used instead. This method also updates the internal list and sets the first value of the list as the selected value, if applicable.

Parameters:

items - the collection of items to be set in the combo list

Returns:

the updated ListBoxListDataView instance reflecting the new items

setFirstValue

protected void setFirstValue()

Sets the current value of the combo list to the first item in the list. If the list is empty, the value is set to null. This method ensures that the combo list initializes its value to the first available item in its data collection, or remains unset if no items exist.

getIndex

public int getIndex()

Retrieves the index of the item currently selected or set as the value of the combo list.

Returns:

the index of the current value in the list, or -1 if the value is not found

getIndex

public int getIndex(T item)

Returns the index of the specified item in the list.

Parameters:

item - the item whose index is to be determined; can be null

Returns:

the zero-based index of the specified item in the list, or -1 if the item is not present

getValue

public T getValue(int index)

Retrieves the value at the specified index from the combo list.

Parameters:

index - the position of the item in the list to retrieve. If the index is out of bounds (less than 0 or greater than or equal to the size of the list), null is returned.

Returns:

the value at the specified index, or null if the index is invalid.

getEmptyValue

public T getEmptyValue()

Returns the default empty value for the component. This method is overridden to provide a null value as the representation of an empty value for the generic combo box.

Specified by:

getEmptyValue in interface com.vaadin.flow.component.HasValue<com.vaadin.flow.component.AbstractField.ComponentValueChangeEvent<com.vaadin.flow.component.listbox.ListBox<T>,T>,T>

Overrides:

getEmptyValue in class com.vaadin.flow.component.AbstractField<com.vaadin.flow.component.listbox.ListBox<T>,T>

Returns:

the empty value of the component, which is null