K
- the type of the key elementsV
- the type of the value elementspublic abstract class MapBinding<K,V> extends MapExpression<K,V> implements Binding<<any>>
Binding
of an javafx.collections.ObservableMap
.
MapBinding
provides a simple invalidation-scheme. An extending
class can register dependencies by calling bind(Observable...)
.
If one of the registered dependencies becomes invalid, this
MapBinding
is marked as invalid. With
unbind(Observable...)
listening to dependencies can be stopped.
To provide a concrete implementation of this class, the method
computeValue()
has to be implemented to calculate the value of this
binding based on the current state of the dependencies. It is called when
get()
is called for an invalid binding.
See DoubleBinding
for an example how this base class can be extended.
Binding
,
MapExpression
Type | Property and Description |
---|---|
ReadOnlyBooleanProperty |
empty
A boolean property that is
true , if the map is empty. |
ReadOnlyIntegerProperty |
size
An integer property that represents the size of the map.
|
Modifier and Type | Class and Description |
---|---|
private class |
MapBinding.EmptyProperty |
private class |
MapBinding.SizeProperty |
Modifier and Type | Field and Description |
---|---|
private MapBinding.EmptyProperty |
empty0 |
private <any> |
helper |
private <any> |
mapChangeListener |
private BindingHelperObserver |
observer |
private MapBinding.SizeProperty |
size0 |
private boolean |
valid |
private <any> |
value |
Constructor and Description |
---|
MapBinding() |
Modifier and Type | Method and Description |
---|---|
void |
addListener(<any> listener) |
void |
addListener(<any> listener) |
void |
addListener(InvalidationListener listener) |
protected void |
bind(Observable... dependencies)
Start observing the dependencies for changes.
|
protected abstract <any> |
computeValue()
Calculates the current value of this binding.
|
void |
dispose()
A default implementation of
dispose() that is empty. |
ReadOnlyBooleanProperty |
emptyProperty()
A boolean property that is
true , if the map is empty. |
<any> |
get()
Returns the result of
computeValue() . |
<any> |
getDependencies()
A default implementation of
getDependencies() that returns an
empty javafx.collections.ObservableList . |
void |
invalidate()
Mark a binding as invalid.
|
private void |
invalidateProperties() |
boolean |
isValid()
Checks if a binding is valid.
|
protected void |
onInvalidating()
The method onInvalidating() can be overridden by extending classes to
react, if this binding becomes invalid.
|
void |
removeListener(<any> listener) |
void |
removeListener(<any> listener) |
void |
removeListener(InvalidationListener listener) |
ReadOnlyIntegerProperty |
sizeProperty()
An integer property that represents the size of the map.
|
java.lang.String |
toString()
Returns a string representation of this
MapBinding object. |
protected void |
unbind(Observable... dependencies)
Stop observing the dependencies for changes.
|
asString, clear, containsKey, containsValue, entrySet, get, getSize, getValue, isEmpty, isEqualTo, isNotEqualTo, isNotNull, isNull, keySet, mapExpression, put, putAll, remove, size, valueAt, valueAt, values
public ReadOnlyIntegerProperty sizeProperty
sizeProperty
in class MapExpression<K,V>
public ReadOnlyBooleanProperty emptyProperty
emptyProperty
in class MapExpression<K,V>
ReadOnlyBooleanProperty
private final <any> mapChangeListener
private <any> value
private boolean valid
private BindingHelperObserver observer
private <any> helper
private MapBinding.SizeProperty size0
private MapBinding.EmptyProperty empty0
public ReadOnlyIntegerProperty sizeProperty()
MapExpression
sizeProperty
in class MapExpression<K,V>
public ReadOnlyBooleanProperty emptyProperty()
MapExpression
true
, if the map is empty.emptyProperty
in class MapExpression<K,V>
ReadOnlyBooleanProperty
public void addListener(InvalidationListener listener)
public void removeListener(InvalidationListener listener)
public void addListener(<any> listener)
public void removeListener(<any> listener)
public void addListener(<any> listener)
public void removeListener(<any> listener)
protected final void bind(Observable... dependencies)
dependencies
- the dependencies to observeprotected final void unbind(Observable... dependencies)
dependencies
- the dependencies to stop observingpublic void dispose()
dispose()
that is empty.public <any> getDependencies()
getDependencies()
that returns an
empty javafx.collections.ObservableList
.getDependencies
in interface Binding<<any>>
ObservableList
public final <any> get()
computeValue()
. The method
computeValue()
is only called if the binding is invalid. The
result is cached and returned if the binding did not become invalid since
the last call of get()
.protected void onInvalidating()
private void invalidateProperties()
public final void invalidate()
Binding
Binding
next time it is request.invalidate
in interface Binding<<any>>
public final boolean isValid()
Binding
protected abstract <any> computeValue()
Classes extending MapBinding
have to provide an implementation
of computeValue
.
public java.lang.String toString()
MapBinding
object.toString
in class java.lang.Object
MapBinding
object.