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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

added in API level 1
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