Android APIs
public abstract class

AsyncQueryHandler

extends Handler
java.lang.Object
   ↳ android.os.Handler
     ↳ android.content.AsyncQueryHandler

Class Overview

A helper class to help make handling asynchronous ContentResolver queries easier.

Summary

Nested Classes
class AsyncQueryHandler.WorkerArgs  
class AsyncQueryHandler.WorkerHandler  
Public Constructors
AsyncQueryHandler(ContentResolver cr)
Public Methods
final void cancelOperation(int token)
Attempts to cancel operation that has not already started.
void handleMessage(Message msg)
Subclasses must implement this to receive messages.
final void startDelete(int token, Object cookie, Uri uri, String selection, String[] selectionArgs)
This method begins an asynchronous delete.
final void startInsert(int token, Object cookie, Uri uri, ContentValues initialValues)
This method begins an asynchronous insert.
void startQuery(int token, Object cookie, Uri uri, String[] projection, String selection, String[] selectionArgs, String orderBy)
This method begins an asynchronous query.
final void startUpdate(int token, Object cookie, Uri uri, ContentValues values, String selection, String[] selectionArgs)
This method begins an asynchronous update.
Protected Methods
Handler createHandler(Looper looper)
void onDeleteComplete(int token, Object cookie, int result)
Called when an asynchronous delete is completed.
void onInsertComplete(int token, Object cookie, Uri uri)
Called when an asynchronous insert is completed.
void onQueryComplete(int token, Object cookie, Cursor cursor)
Called when an asynchronous query is completed.
void onUpdateComplete(int token, Object cookie, int result)
Called when an asynchronous update is completed.
[Expand]
Inherited Methods
From class android.os.Handler
From class java.lang.Object

Public Constructors

public AsyncQueryHandler (ContentResolver cr)

Added in API level 1

Parameters
cr ContentResolver

Public Methods

public final void cancelOperation (int token)

Added in API level 1

Attempts to cancel operation that has not already started. Note that there is no guarantee that the operation will be canceled. They still may result in a call to on[Query/Insert/Update/Delete]Complete after this call has completed.

Parameters
token int: The token representing the operation to be canceled. If multiple operations have the same token they will all be canceled.

public void handleMessage (Message msg)

Added in API level 1

Subclasses must implement this to receive messages.

Parameters
msg Message

public final void startDelete (int token, Object cookie, Uri uri, String selection, String[] selectionArgs)

Added in API level 1

This method begins an asynchronous delete. When the delete operation is done onDeleteComplete(int, Object, int) is called.

Parameters
token int: A token passed into onDeleteComplete(int, Object, int) to identify the delete operation.
cookie Object: An object that gets passed into onDeleteComplete(int, Object, int)
uri Uri: the Uri passed to the delete operation.
selection String: the where clause.
selectionArgs String

public final void startInsert (int token, Object cookie, Uri uri, ContentValues initialValues)

Added in API level 1

This method begins an asynchronous insert. When the insert operation is done onInsertComplete(int, Object, Uri) is called.

Parameters
token int: A token passed into onInsertComplete(int, Object, Uri) to identify the insert operation.
cookie Object: An object that gets passed into onInsertComplete(int, Object, Uri)
uri Uri: the Uri passed to the insert operation.
initialValues ContentValues: the ContentValues parameter passed to the insert operation.

public void startQuery (int token, Object cookie, Uri uri, String[] projection, String selection, String[] selectionArgs, String orderBy)

Added in API level 1

This method begins an asynchronous query. When the query is done onQueryComplete(int, Object, Cursor) is called.

Parameters
token int: A token passed into onQueryComplete(int, Object, Cursor) to identify the query.
cookie Object: An object that gets passed into onQueryComplete(int, Object, Cursor)
uri Uri: The URI, using the content:// scheme, for the content to retrieve.
projection String: A list of which columns to return. Passing null will return all columns, which is discouraged to prevent reading data from storage that isn't going to be used.
selection String: A filter declaring which rows to return, formatted as an SQL WHERE clause (excluding the WHERE itself). Passing null will return all rows for the given URI.
selectionArgs String: You may include ?s in selection, which will be replaced by the values from selectionArgs, in the order that they appear in the selection. The values will be bound as Strings.
orderBy String: How to order the rows, formatted as an SQL ORDER BY clause (excluding the ORDER BY itself). Passing null will use the default sort order, which may be unordered.

public final void startUpdate (int token, Object cookie, Uri uri, ContentValues values, String selection, String[] selectionArgs)

Added in API level 1

This method begins an asynchronous update. When the update operation is done onUpdateComplete(int, Object, int) is called.

Parameters
token int: A token passed into onUpdateComplete(int, Object, int) to identify the update operation.
cookie Object: An object that gets passed into onUpdateComplete(int, Object, int)
uri Uri: the Uri passed to the update operation.
values ContentValues: the ContentValues parameter passed to the update operation.
selection String
selectionArgs String

Protected Methods

protected Handler createHandler (Looper looper)

Added in API level 1

Parameters
looper Looper
Returns
Handler

protected void onDeleteComplete (int token, Object cookie, int result)

Added in API level 1

Called when an asynchronous delete is completed.

Parameters
token int: the token to identify the query, passed in from startDelete(int, Object, Uri, String, String[]).
cookie Object: the cookie object that's passed in from startDelete(int, Object, Uri, String, String[]).
result int: the result returned from the delete operation

protected void onInsertComplete (int token, Object cookie, Uri uri)

Added in API level 1

Called when an asynchronous insert is completed.

Parameters
token int: the token to identify the query, passed in from startInsert(int, Object, Uri, ContentValues).
cookie Object: the cookie object that's passed in from startInsert(int, Object, Uri, ContentValues).
uri Uri: the uri returned from the insert operation.

protected void onQueryComplete (int token, Object cookie, Cursor cursor)

Added in API level 1

Called when an asynchronous query is completed.

Parameters
token int: the token to identify the query, passed in from startQuery(int, Object, Uri, String[], String, String[], String).
cookie Object: the cookie object passed in from startQuery(int, Object, Uri, String[], String, String[], String).
cursor Cursor: The cursor holding the results from the query.

protected void onUpdateComplete (int token, Object cookie, int result)

Added in API level 1

Called when an asynchronous update is completed.

Parameters
token int: the token to identify the query, passed in from startUpdate(int, Object, Uri, ContentValues, String, String[]).
cookie Object: the cookie object that's passed in from startUpdate(int, Object, Uri, ContentValues, String, String[]).
result int: the result returned from the update operation