Module javafx.base
Package javafx.beans.property

Class LongProperty

java.lang.Object
javafx.beans.binding.NumberExpressionBase
javafx.beans.binding.LongExpression
javafx.beans.property.ReadOnlyLongProperty
javafx.beans.property.LongProperty
All Implemented Interfaces:
NumberExpression, Observable, Property<Number>, ReadOnlyProperty<Number>, ObservableLongValue, ObservableNumberValue, ObservableValue<Number>, WritableLongValue, WritableNumberValue, WritableValue<Number>
Direct Known Subclasses:
JavaBeanLongProperty, LongPropertyBase
public abstract class LongProperty extends ReadOnlyLongProperty implements Property<Number>, WritableLongValue
This class defines a Property wrapping a long value.

The value of a LongProperty can be get and set with ObservableLongValue.get(), LongExpression.getValue(), WritableLongValue.set(long), and setValue(Number).

A property can be bound and unbound unidirectional with Property.bind(ObservableValue) and Property.unbind(). Bidirectional bindings can be created and removed with bindBidirectional(Property) and unbindBidirectional(Property).

The context of a LongProperty can be read with ReadOnlyProperty.getBean() and ReadOnlyProperty.getName().

Note: setting or binding this property to a null value will set the property to "0.0". See setValue(java.lang.Number).

Since:
JavaFX 2.0
See Also:

  • Constructor Details

    • LongProperty

      public LongProperty()
      Creates a default LongProperty.

  • Method Details

    • setValue

      public void setValue(Number v)
      Set the wrapped value.
      Specified by:
      setValue in interface WritableLongValue
      Specified by:
      setValue in interface WritableValue<Number>
      Parameters:
      v - The new value

    • bindBidirectional

      public void bindBidirectional(Property<Number> other)
      Create a bidirectional binding between this Property and another one. Bidirectional bindings exists independently of unidirectional bindings. So it is possible to add unidirectional binding to a property with bidirectional binding and vice-versa. However, this practice is discouraged.

      It is possible to have multiple bidirectional bindings of one Property.

      JavaFX bidirectional binding implementation use weak listeners. This means bidirectional binding does not prevent properties from being garbage collected.

      Specified by:
      bindBidirectional in interface Property<Number>
      Parameters:
      other - the other Property

    • unbindBidirectional

      public void unbindBidirectional(Property<Number> other)
      Removes a bidirectional binding between this Property and another one. If no bidirectional binding between the properties exists, calling this method has no effect. It is possible to unbind by a call on the second property. This code will work: 
           property1.bindBidirectional(property2);
     property2.unbindBidirectional(property1);
      Specified by:
      unbindBidirectional in interface Property<Number>
      Parameters:
      other - the other Property

    • toString

      public String toString()
      Returns a string representation of this LongProperty object.
      Overrides:
      toString in class ReadOnlyLongProperty
      Returns:
      a string representation of this LongProperty object.

    • longProperty

      public static LongProperty longProperty(Property<Long> property)
      Returns a LongProperty that wraps a Property and is bidirectionally bound to it. Changing this property will result in a change of the original property.

      This is very useful when bidirectionally binding an ObjectProperty<Long> and a LongProperty. 

         LongProperty longProperty = new SimpleLongProperty(1L);
   ObjectProperty<Long> objectProperty = new SimpleObjectProperty<>(2L);

   // Need to keep the reference as bidirectional binding uses weak references
   LongProperty objectAsLong = LongProperty.longProperty(objectProperty);

   longProperty.bindBidirectional(objectAsLong);
      Another approach is to convert the LongProperty to ObjectProperty using asObject() method.

      Note: null values in the source property will be interpreted as 0L

      Parameters:
      property - The source Property
      Returns:
      A LongProperty that wraps the Property
      Throws:
      NullPointerException - if property is null
      Since:
      JavaFX 8.0
      See Also:

    • asObject

      public ObjectProperty<Long> asObject()
      Creates an ObjectProperty that bidirectionally bound to this LongProperty. If the value of this LongProperty changes, the value of the ObjectProperty will be updated automatically and vice-versa.

      Can be used for binding an ObjectProperty to LongProperty. 

         LongProperty longProperty = new SimpleLongProperty(1L);
   ObjectProperty<Long> objectProperty = new SimpleObjectProperty<>(2L);

   objectProperty.bind(longProperty.asObject());
      Overrides:
      asObject in class ReadOnlyLongProperty
      Returns:
      the new ObjectProperty
      Since:
      JavaFX 8.0