Class ListExpression<E>

java.lang.Object

javafx.beans.binding.ListExpression<E>

Type Parameters:: E - the type of the List elements.

All Implemented Interfaces:: Iterable<E>, Collection<E>, List<E>, Observable, ObservableListValue<E>, ObservableObjectValue<ObservableList<E>>, ObservableValue<ObservableList<E>>, ObservableList<E>

Direct Known Subclasses:: ListBinding, ReadOnlyListProperty

public abstract class ListExpression<E>
extends Object
implements ObservableListValue<E>

ListExpression is an ObservableListValue plus additional convenience methods to generate bindings in a fluent style.

A concrete sub-class of ListExpression has to implement the method ObservableObjectValue.get(), which provides the actual value of this expression.

If the wrapped list of a ListExpression is null, all methods implementing the List interface will behave as if they were applied to an immutable empty list.

Since:: JavaFX 2.1

Property Summary

Properties
Type	Property	Description
`abstract ReadOnlyBooleanProperty`	`empty`	A boolean property that is `true`, if the list is empty.
`abstract ReadOnlyIntegerProperty`	`size`	An integer property that represents the size of the list.

Constructor Summary

Constructors
Constructor	Description
`ListExpression()`	Creates a default `ListExpression`.

Method Summary

Modifier and Type	Method	Description
`StringBinding`	`asString()`	Creates a `StringBinding` that holds the value of the `ListExpression` turned into a `String`.
`abstract ReadOnlyBooleanProperty`	`emptyProperty()`	A boolean property that is `true`, if the list is empty.
`int`	`getSize()`	The size of the list
`BooleanBinding`	`isEqualTo(ObservableList<?> other)`	Creates a new `BooleanBinding` that holds `true` if this list is equal to another `ObservableList`.
`BooleanBinding`	`isNotEqualTo(ObservableList<?> other)`	Creates a new `BooleanBinding` that holds `true` if this list is not equal to another `ObservableList`.
`BooleanBinding`	`isNotNull()`	Creates a new `BooleanBinding` that holds `true` if the wrapped list is not `null`.
`BooleanBinding`	`isNull()`	Creates a new `BooleanBinding` that holds `true` if the wrapped list is `null`.
`static <E> ListExpression<E>`	`listExpression(ObservableListValue<E> value)`	Returns a `ListExpression` that wraps a `ObservableListValue`.
`abstract ReadOnlyIntegerProperty`	`sizeProperty()`	An integer property that represents the size of the list.
`ObjectBinding<E>`	`valueAt(int index)`	Creates a new `ObjectBinding` that contains the element at the specified position.
`ObjectBinding<E>`	`valueAt(ObservableIntegerValue index)`	Creates a new `ObjectBinding` that contains the element at the specified position.

Methods declared in class java.lang.Object

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

Methods declared in interface java.util.Collection

parallelStream, removeIf, stream, toArray

Methods declared in interface java.lang.Iterable

forEach

Methods declared in interface java.util.List

add, add, addAll, addAll, clear, contains, containsAll, equals, get, hashCode, indexOf, isEmpty, iterator, lastIndexOf, listIterator, listIterator, remove, remove, removeAll, replaceAll, retainAll, set, size, sort, spliterator, subList, toArray, toArray

Methods declared in interface javafx.beans.Observable

addListener, removeListener

Methods declared in interface javafx.collections.ObservableList

addAll, addListener, filtered, remove, removeAll, removeListener, retainAll, setAll, setAll, sorted, sorted

Methods declared in interface javafx.beans.value.ObservableObjectValue

get

Methods declared in interface javafx.beans.value.ObservableValue

addListener, getValue, removeListener

Property Details

size

public abstract ReadOnlyIntegerProperty sizeProperty

An integer property that represents the size of the list.

See Also:: getSize()

empty

public abstract ReadOnlyBooleanProperty emptyProperty

A boolean property that is true, if the list is empty.

See Also:: List.isEmpty()

Constructor Details

ListExpression

public ListExpression()

Creates a default ListExpression.

Method Details

listExpression

public static <E> ListExpression<E> listExpression(ObservableListValue<E> value)

Returns a ListExpression that wraps a ObservableListValue. If the ObservableListValue is already a ListExpression, it will be returned. Otherwise a new ListBinding is created that is bound to the ObservableListValue.

Type Parameters:: E - the type of the wrapped List
Parameters:: value - The source ObservableListValue
Returns:: A ListExpression that wraps the ObservableListValue if necessary
Throws:: NullPointerException - if value is null

getSize

public int getSize()

The size of the list

Returns:: the size

sizeProperty

public abstract ReadOnlyIntegerProperty sizeProperty()

An integer property that represents the size of the list.

See Also:: getSize()

emptyProperty

public abstract ReadOnlyBooleanProperty emptyProperty()

A boolean property that is true, if the list is empty.

See Also:: List.isEmpty()

valueAt

public ObjectBinding<E> valueAt(int index)

Creates a new ObjectBinding that contains the element at the specified position. If index points behind the list, the ObjectBinding contains null.

Parameters:: index - the index of the element
Returns:: the ObjectBinding
Throws:: IllegalArgumentException - if index < 0

valueAt

public ObjectBinding<E> valueAt(ObservableIntegerValue index)

Creates a new ObjectBinding that contains the element at the specified position. If index points outside of the list, the ObjectBinding contains null.

Parameters:: index - the index of the element
Returns:: the ObjectBinding
Throws:: NullPointerException - if index is null

isEqualTo

public BooleanBinding isEqualTo(ObservableList<?> other)

Creates a new BooleanBinding that holds true if this list is equal to another ObservableList.

Parameters:: other - the other ObservableList
Returns:: the new BooleanBinding
Throws:: NullPointerException - if other is null

isNotEqualTo

public BooleanBinding isNotEqualTo(ObservableList<?> other)

Creates a new BooleanBinding that holds true if this list is not equal to another ObservableList.

Parameters:: other - the other ObservableList
Returns:: the new BooleanBinding
Throws:: NullPointerException - if other is null

isNull

public BooleanBinding isNull()

Creates a new BooleanBinding that holds true if the wrapped list is null.

Returns:: the new BooleanBinding

isNotNull

public BooleanBinding isNotNull()

Creates a new BooleanBinding that holds true if the wrapped list is not null.

Returns:: the new BooleanBinding

asString

public StringBinding asString()

Creates a StringBinding that holds the value of the ListExpression turned into a String. If the value of this ListExpression changes, the value of the StringBinding will be updated automatically.

Returns:: the new StringBinding

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Documentation extracted from JavaFX API Documentation.
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