Observable


public abstract class Observable
extends Object

java.lang.Object
   ↳ android.database.Observable<T>


Provides methods for registering or unregistering arbitrary observers in an ArrayList. This abstract class is intended to be subclassed and specialized to maintain a registry of observers of specific types and dispatch notifications to them.

Summary

Fields

protected final ArrayList<T> mObservers

The list of observers.

Public constructors

Observable()

Public methods

void registerObserver(T observer)

Adds an observer to the list.

void unregisterAll()

Remove all registered observers.

void unregisterObserver(T observer)

Removes a previously registered observer.

Inherited methods

Fields

mObservers

Added in API level 1
protected final ArrayList<T> mObservers

The list of observers. An observer can be in the list at most once and will never be null.

Public constructors

Observable

public Observable ()

Public methods

registerObserver

Added in API level 1
public void registerObserver (T observer)

Adds an observer to the list. The observer cannot be null and it must not already be registered.

Parameters
observer T: the observer to register

Throws
IllegalArgumentException the observer is null
IllegalStateException the observer is already registered

unregisterAll

Added in API level 1
public void unregisterAll ()

Remove all registered observers.

unregisterObserver

Added in API level 1
public void unregisterObserver (T observer)

Removes a previously registered observer. The observer must not be null and it must already have been registered.

Parameters
observer T: the observer to unregister

Throws
IllegalArgumentException the observer is null
IllegalStateException the observer is not yet registered