Added in API level 1

Summary: Ctors | Methods | Inherited Methods

ContentObserver

---

Kotlin |Java

public abstract class ContentObserver
extends Object

java.lang.Object
↳	android.database.ContentObserver

Known direct subclasses AbstractCursor.SelfContentObserver, Loader.ForceLoadContentObserver AbstractCursor.SelfContentObserver Cursors use this class to track changes others make to their URI.  Loader.ForceLoadContentObserver This class was deprecated in API level 28. Use Loader.ForceLoadContentObserver

---

Receives call backs for changes to content. Must be implemented by objects which are added to a ContentObservable.

Summary

Public constructors
ContentObserver(Handler handler) Creates a content observer.

Public methods
boolean	deliverSelfNotifications() Returns true if this observer is interested receiving self-change notifications.
final void	dispatchChange(boolean selfChange) This method was deprecated in API level 16. Callers should migrate towards using a richer overload that provides more details about the change, such as dispatchChange(boolean, java.util.Collection, int).
final void	dispatchChange(boolean selfChange, Uri uri) Dispatches a change notification to the observer.
final void	dispatchChange(boolean selfChange, Uri uri, int flags) Dispatches a change notification to the observer.
final void	dispatchChange(boolean selfChange, Collection<Uri> uris, int flags) Dispatches a change notification to the observer.
void	onChange(boolean selfChange, Uri uri, int flags) This method is called when a content change occurs.
void	onChange(boolean selfChange) This method is called when a content change occurs.
void	onChange(boolean selfChange, Uri uri) This method is called when a content change occurs.
void	onChange(boolean selfChange, Collection<Uri> uris, int flags) This method is called when a content change occurs.

Inherited methods

From class java.lang.Object Object clone() Creates and returns a copy of this object. boolean equals(Object obj) Indicates whether some other object is "equal to" this one. void finalize() Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. final Class<?> getClass() Returns the runtime class of this Object. int hashCode() Returns a hash code value for the object. final void notify() Wakes up a single thread that is waiting on this object's monitor. final void notifyAll() Wakes up all threads that are waiting on this object's monitor. String toString() Returns a string representation of the object. final void wait(long timeoutMillis, int nanos) Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed. final void wait(long timeoutMillis) Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed. final void wait() Causes the current thread to wait until it is awakened, typically by being notified or interrupted.

Public constructors

ContentObserver

Added in API level 1

public ContentObserver (Handler handler)

Creates a content observer.

Parameters
handler	Handler: The handler to run onChange(boolean) on, or null if none.

Public methods

deliverSelfNotifications

Added in API level 1

public boolean deliverSelfNotifications ()

Returns true if this observer is interested receiving self-change notifications. Subclasses should override this method to indicate whether the observer is interested in receiving notifications for changes that it made to the content itself.

Returns
boolean	True if self-change notifications should be delivered to the observer.

dispatchChange

Added in API level 1
Deprecated in API level 16

public final void dispatchChange (boolean selfChange)

This method was deprecated in API level 16.
Callers should migrate towards using a richer overload that provides more details about the change, such as dispatchChange(boolean, java.util.Collection, int).

Dispatches a change notification to the observer.

If a Handler was supplied to the ContentObserver constructor, then a call to the onChange(boolean) method is posted to the handler's message queue. Otherwise, the onChange(boolean) method is invoked immediately on this thread.

Parameters
selfChange	boolean

dispatchChange

Added in API level 16

public final void dispatchChange (boolean selfChange, 
                Uri uri)

Dispatches a change notification to the observer. Includes the changed content Uri when available.

If a Handler was supplied to the ContentObserver constructor, then a call to the onChange(boolean) method is posted to the handler's message queue. Otherwise, the onChange(boolean) method is invoked immediately on this thread.

Parameters
selfChange	boolean: True if this is a self-change notification.
uri	Uri: The Uri of the changed content. This value may be null.

dispatchChange

Added in API level 30

public final void dispatchChange (boolean selfChange, 
                Uri uri, 
                int flags)

Dispatches a change notification to the observer. Includes the changed content Uri when available.

If a Handler was supplied to the ContentObserver constructor, then a call to the onChange(boolean) method is posted to the handler's message queue. Otherwise, the onChange(boolean) method is invoked immediately on this thread.

Parameters
selfChange	boolean: True if this is a self-change notification.
uri	Uri: The Uri of the changed content. This value may be null.
flags	int: Flags indicating details about this change. Value is either 0 or a combination of ContentResolver.NOTIFY_SYNC_TO_NETWORK, ContentResolver.NOTIFY_SKIP_NOTIFY_FOR_DESCENDANTS, ContentResolver.NOTIFY_INSERT, ContentResolver.NOTIFY_UPDATE, and ContentResolver.NOTIFY_DELETE

dispatchChange

Added in API level 30

public final void dispatchChange (boolean selfChange, 
                Collection<Uri> uris, 
                int flags)

Dispatches a change notification to the observer. Includes the changed content Uris when available.

If a Handler was supplied to the ContentObserver constructor, then a call to the onChange(boolean) method is posted to the handler's message queue. Otherwise, the onChange(boolean) method is invoked immediately on this thread.

Parameters
selfChange	boolean: True if this is a self-change notification.
uris	Collection: The Uri of the changed content. This value cannot be null.
flags	int: Flags indicating details about this change. Value is either 0 or a combination of ContentResolver.NOTIFY_SYNC_TO_NETWORK, ContentResolver.NOTIFY_SKIP_NOTIFY_FOR_DESCENDANTS, ContentResolver.NOTIFY_INSERT, ContentResolver.NOTIFY_UPDATE, and ContentResolver.NOTIFY_DELETE

onChange

Added in API level 30

public void onChange (boolean selfChange, 
                Uri uri, 
                int flags)

This method is called when a content change occurs. Includes the changed content Uri when available.

Subclasses should override this method to handle content changes. To ensure correct operation on older versions of the framework that did not provide richer arguments, applications should implement all overloads.

Parameters
selfChange	boolean: True if this is a self-change notification.
uri	Uri: The Uri of the changed content. This value may be null.
flags	int: Flags indicating details about this change. Value is either 0 or a combination of ContentResolver.NOTIFY_SYNC_TO_NETWORK, ContentResolver.NOTIFY_SKIP_NOTIFY_FOR_DESCENDANTS, ContentResolver.NOTIFY_INSERT, ContentResolver.NOTIFY_UPDATE, and ContentResolver.NOTIFY_DELETE

onChange

Added in API level 1

public void onChange (boolean selfChange)

This method is called when a content change occurs.

Subclasses should override this method to handle content changes.

Parameters
selfChange	boolean: True if this is a self-change notification.

onChange

Added in API level 16

public void onChange (boolean selfChange, 
                Uri uri)

This method is called when a content change occurs. Includes the changed content Uri when available.

Subclasses should override this method to handle content changes. To ensure correct operation on older versions of the framework that did not provide richer arguments, applications should implement all overloads.

Example implementation:

 // Implement the onChange(boolean) method to delegate the change notification to
 // the onChange(boolean, Uri) method to ensure correct operation on older versions
 // of the framework that did not have the onChange(boolean, Uri) method.
 @Override
 public void onChange(boolean selfChange) {
     onChange(selfChange, null);
 }

 // Implement the onChange(boolean, Uri) method to take advantage of the new Uri argument.
 @Override
 public void onChange(boolean selfChange, Uri uri) {
     // Handle change.
 }
 

Parameters
selfChange	boolean: True if this is a self-change notification.
uri	Uri: The Uri of the changed content. This value may be null.

onChange

Added in API level 30

public void onChange (boolean selfChange, 
                Collection<Uri> uris, 
                int flags)

This method is called when a content change occurs. Includes the changed content Uris when available.

Subclasses should override this method to handle content changes. To ensure correct operation on older versions of the framework that did not provide richer arguments, applications should implement all overloads.

Parameters
selfChange	boolean: True if this is a self-change notification.
uris	Collection: The Uris of the changed content. This value cannot be null.
flags	int: Flags indicating details about this change. Value is either 0 or a combination of ContentResolver.NOTIFY_SYNC_TO_NETWORK, ContentResolver.NOTIFY_SKIP_NOTIFY_FOR_DESCENDANTS, ContentResolver.NOTIFY_INSERT, ContentResolver.NOTIFY_UPDATE, and ContentResolver.NOTIFY_DELETE