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Android APIs
public abstract class

Observable

extends Object
java.lang.Object
   ↳ android.database.Observable<T>
Known Direct Subclasses

Class Overview

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.
[Expand]
Inherited Methods
From class java.lang.Object

Fields

protected final ArrayList<T> mObservers

Since: API Level 1

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

Public Constructors

public Observable ()

Since: API Level 1

Public Methods

public void registerObserver (T observer)

Since: API Level 1

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

Parameters
observer the observer to register
Throws
IllegalArgumentException the observer is null
IllegalStateException the observer is already registered

public void unregisterAll ()

Since: API Level 1

Remove all registered observers.

public void unregisterObserver (T observer)

Since: API Level 1

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

Parameters
observer the observer to unregister
Throws
IllegalArgumentException the observer is null
IllegalStateException the observer is not yet registered