android.databinding

Class CallbackRegistry<C,T,A>

java.lang.Object

android.databinding.CallbackRegistry<C,T,A>

Type Parameters:

C - The callback type.

T - The notification sender type. Typically this is the containing class.

A - Opaque argument used to pass additional data beyond an int.

All Implemented Interfaces:

java.lang.Cloneable

Direct Known Subclasses:

ListChangeRegistry, MapChangeRegistry, PropertyChangeRegistry

public class CallbackRegistry<C,T,A>
extends java.lang.Object
implements java.lang.Cloneable

Tracks callbacks for the event. 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.

This class supports only callbacks with at most two parameters. Typically, these are the notification originator and a parameter, but these may be used as required. If more than two parameters are required or primitive types must be used, A should be some kind of containing structure that the subclass may reuse between notifications.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	CallbackRegistry.NotifierCallback<C,T,A> Class used to notify events from CallbackRegistry.

Constructor Summary

Constructors

Constructor and Description
CallbackRegistry(CallbackRegistry.NotifierCallback<C,T,A> notifier) Creates an EventRegistry that notifies the event with notifier.

Method Summary

Methods

Modifier and Type	Method and Description
void	add(C callback) Add a callback to be notified.
void	clear() Removes all callbacks from the list.
CallbackRegistry<C,T,A>	clone()
java.util.ArrayList<C>	copyListeners() Makes a copy of the registered callbacks and returns it.
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.

Methods inherited from class java.lang.Object

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

Constructor Detail

CallbackRegistry

public CallbackRegistry(CallbackRegistry.NotifierCallback<C,T,A> notifier)

Creates an EventRegistry that notifies the event with notifier.

Parameters:

notifier - The class to use to notify events.

Method Detail

notifyCallbacks

public void notifyCallbacks(T sender,
                   int arg,
                   A arg2)

Notify all callbacks.

Parameters:

sender - The originator. This is an opaque parameter passed to CallbackRegistry.NotifierCallback#onNotifyCallback(Object, Object, int, A)

arg - An opaque parameter passed to CallbackRegistry.NotifierCallback#onNotifyCallback(Object, Object, int, A)

arg2 - An opaque parameter passed to CallbackRegistry.NotifierCallback#onNotifyCallback(Object, Object, int, A)

add

public 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 - The callback to add.

remove

public void remove(C callback)

Remove a callback. This callback won't be notified after this call completes.

Parameters:

callback - The callback to remove.

copyListeners

public java.util.ArrayList<C> copyListeners()

Makes a copy of the registered callbacks and returns it.

Returns:

a copy of the registered callbacks.

isEmpty

public boolean isEmpty()

Returns true if there are no registered callbacks or false otherwise.

Returns:

true if there are no registered callbacks or false otherwise.

clear

public void clear()

Removes all callbacks from the list.

clone

public CallbackRegistry<C,T,A> clone()

Overrides:

clone in class java.lang.Object