public class ExpressionValue extends ObservableValueBase<Object>
Constructor and Description |
---|
ExpressionValue(Object namespace,
Expression expression,
Class<?> type) |
Modifier and Type | Method and Description |
---|---|
void |
addListener(ChangeListener<? super Object> listener)
Adds a
ChangeListener which will be notified whenever the value
of the ObservableValue changes. |
void |
addListener(InvalidationListener listener)
Adds an
InvalidationListener which will be notified whenever the
Observable becomes invalid. |
Object |
getValue()
Returns the current value of this
ObservableValue |
void |
removeListener(ChangeListener<? super Object> listener)
Removes the given listener from the list of listeners, that are notified
whenever the value of the
ObservableValue changes. |
void |
removeListener(InvalidationListener listener)
Removes the given listener from the list of listeners, that are notified
whenever the value of the
Observable becomes invalid. |
fireValueChangedEvent
public ExpressionValue(Object namespace, Expression expression, Class<?> type)
public Object getValue()
ObservableValue
ObservableValue
public void addListener(InvalidationListener listener)
ObservableValueBase
InvalidationListener
which will be notified whenever the
Observable
becomes invalid. If the same
listener is added more than once, then it will be notified more than
once. That is, no check is made to ensure uniqueness.
Note that the same actual InvalidationListener
instance may be
safely registered for different Observables
.
The Observable
stores a strong reference to the listener
which will prevent the listener from being garbage collected and may
result in a memory leak. It is recommended to either unregister a
listener by calling removeListener
after use or to use an instance of
WeakInvalidationListener
avoid this situation.
addListener
in interface Observable
addListener
in class ObservableValueBase<Object>
listener
- The listener to registerObservable.removeListener(InvalidationListener)
public void removeListener(InvalidationListener listener)
ObservableValueBase
Observable
becomes invalid.
If the given listener has not been previously registered (i.e. it was never added) then this method call is a no-op. If it had been previously added then it will be removed. If it had been added more than once, then only the first occurrence will be removed.
removeListener
in interface Observable
removeListener
in class ObservableValueBase<Object>
listener
- The listener to removeObservable.addListener(InvalidationListener)
public void addListener(ChangeListener<? super Object> listener)
ObservableValueBase
ChangeListener
which will be notified whenever the value
of the ObservableValue
changes. If the same listener is added
more than once, then it will be notified more than once. That is, no
check is made to ensure uniqueness.
Note that the same actual ChangeListener
instance may be safely
registered for different ObservableValues
.
The ObservableValue
stores a strong reference to the listener
which will prevent the listener from being garbage collected and may
result in a memory leak. It is recommended to either unregister a
listener by calling removeListener
after use or to use an instance of
WeakChangeListener
avoid this situation.
addListener
in interface ObservableValue<Object>
addListener
in class ObservableValueBase<Object>
listener
- The listener to registerObservableValue.removeListener(ChangeListener)
public void removeListener(ChangeListener<? super Object> listener)
ObservableValueBase
ObservableValue
changes.
If the given listener has not been previously registered (i.e. it was never added) then this method call is a no-op. If it had been previously added then it will be removed. If it had been added more than once, then only the first occurrence will be removed.
removeListener
in interface ObservableValue<Object>
removeListener
in class ObservableValueBase<Object>
listener
- The listener to removeObservableValue.addListener(ChangeListener)
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