public
class
CallbackRegistry
extends Object
implements
Cloneable
| java.lang.Object | |
| ↳ | android.databinding.CallbackRegistry<C, T, A> |
 Known Direct Subclasses
|
A utility for storing and notifying callbacks. This class supports reentrant modification of the callbacks during notification without adversely disrupting notifications. A common pattern for callbacks is to receive a notification and then remove themselves. This class handles this behavior with constant memory under most circumstances.
A subclass of CallbackRegistry.NotifierCallback must be passed to
the constructor to define how notifications should be called. That implementation
does the actual notification on the listener. It is typically a static instance
that can be reused for all similar CallbackRegistries.
This class supports only callbacks with at most three parameters.
Typically, these are the notification originator and a parameter, with another to
indicate which method to call, but these may be used as required. If more than
three parameters are required or primitive types other than the single int provided
must be used, A should be some kind of containing structure that
the subclass may reuse between notifications.
Nested classes | |
|---|---|
class |
CallbackRegistry.NotifierCallback<C, T, A>
Class used to notify events from CallbackRegistry. |
Public constructors | |
|---|---|
CallbackRegistry(NotifierCallback<C, T, A> notifier)
Creates an EventRegistry that notifies the event with notifier. |
|
Public methods | |
|---|---|
void
|
add(C callback)
Add a callback to be notified. |
void
|
clear()
Removes all callbacks from the list. |
CallbackRegistry<C, T, A>
|
clone()
Creates and returns a copy of this object. |
ArrayList<C>
|
copyCallbacks()
Makes a copy of the registered callbacks and returns it. |
void
|
copyCallbacks(List<C> callbacks)
Modifies |
boolean
|
isEmpty()
Returns true if there are no registered callbacks or false otherwise. |
void
|
notifyCallbacks(T sender, int arg, A arg2)
Notify all callbacks. |
void
|
remove(C callback)
Remove a callback. |
Inherited methods | |
|---|---|
From
class
java.lang.Object
| |
CallbackRegistry (NotifierCallback<C, T, A> notifier)
Creates an EventRegistry that notifies the event with notifier.
| Parameters | |
|---|---|
notifier |
NotifierCallback:
The class to use to notify events.
|
void add (C callback)
Add a callback to be notified. If the callback is already in the list, another won't be added. This does not affect current notifications.
| Parameters | |
|---|---|
callback |
C:
The callback to add.
|
void clear ()
Removes all callbacks from the list.
CallbackRegistry<C, T, A> clone ()
Creates and returns a copy of this object. The precise meaning
of "copy" may depend on the class of the object. The general
intent is that, for any object x, the expression:
will be true, and that the expression:x.clone() != x
will bex.clone().getClass() == x.getClass()
Developers
true, but these are not absolute requirements.
While it is typically the case that:
will bex.clone().equals(x)
true, this is not an absolute requirement.
By convention, the returned object should be obtained by calling
super.clone. If a class and all of its superclasses (except
Object) obey this convention, it will be the case that
x.clone().getClass() == x.getClass().
By convention, the object returned by this method should be independent
of this object (which is being cloned). To achieve this independence,
it may be necessary to modify one or more fields of the object returned
by super.clone before returning it. Typically, this means
copying any mutable objects that comprise the internal "deep structure"
of the object being cloned and replacing the references to these
objects with references to the copies. If a class contains only
primitive fields or references to immutable objects, then it is usually
the case that no fields in the object returned by super.clone
need to be modified.
The method clone for class Object performs a
specific cloning operation. First, if the class of this object does
not implement the interface Cloneable, then a
CloneNotSupportedException is thrown. Note that all arrays
are considered to implement the interface Cloneable and that
the return type of the clone method of an array type T[]
is T[] where T is any reference or primitive type.
Otherwise, this method creates a new instance of the class of this
object and initializes all its fields with exactly the contents of
the corresponding fields of this object, as if by assignment; the
contents of the fields are not themselves cloned. Thus, this method
performs a "shallow copy" of this object, not a "deep copy" operation.
The class Object does not itself implement the interface
Cloneable, so calling the clone method on an object
whose class is Object will result in throwing an
exception at run time.
| Returns | |
|---|---|
CallbackRegistry<C, T, A> |
A copy of the CallbackRegistry with all callbacks listening to both instances. |
ArrayList<C> copyCallbacks ()
Makes a copy of the registered callbacks and returns it.
| Returns | |
|---|---|
ArrayList<C> |
a copy of the registered callbacks. |
void copyCallbacks (List<C> callbacks)
Modifies callbacks to contain all callbacks in the CallbackRegistry.
| Parameters | |
|---|---|
callbacks |
List:
modified to contain all callbacks registered to receive events.
|
boolean isEmpty ()
Returns true if there are no registered callbacks or false otherwise.
| Returns | |
|---|---|
boolean |
true if there are no registered callbacks or false otherwise. |
void notifyCallbacks (T sender,
int arg,
A arg2)
Notify all callbacks.
| Parameters | |
|---|---|
sender |
T:
The originator. This is an opaque parameter passed to
onNotifyCallback(Object, Object, int, Object) |
arg |
int:
An opaque parameter passed to
onNotifyCallback(Object, Object, int, Object) |
arg2 |
A:
An opaque parameter passed to
onNotifyCallback(Object, Object, int, Object)
|
void remove (C callback)
Remove a callback. This callback won't be notified after this call completes.
| Parameters | |
|---|---|
callback |
C:
The callback to remove.
|