AbstractCursor | API reference | Android Developers (original) (raw)

abstract class AbstractCursor : CrossProcessCursor

This is an abstract cursor class that handles a lot of the common code that all cursors need to deal with and is provided for convenience reasons.

Summary

Nested classes
open	SelfContentObserver Cursors use this class to track changes others make to their URI.

Public constructors
AbstractCursor()

Public methods
open Unit	close()
open Unit	copyStringToBuffer(columnIndex: Int, buffer: CharArrayBuffer!)
open Unit	deactivate()
open Unit	fillWindow(position: Int, window: CursorWindow!)
open ByteArray!	getBlob(column: Int)
open Int	getColumnCount()
open Int	getColumnIndex(columnName: String!)
open Int	getColumnIndexOrThrow(columnName: String!)
open String!	getColumnName(columnIndex: Int)
abstract Array<String!>!	getColumnNames()
abstract Int	getCount()
abstract Double	getDouble(column: Int)
open Bundle!	getExtras()
abstract Float	getFloat(column: Int)
abstract Int	getInt(column: Int)
abstract Long	getLong(column: Int)
open Uri!	getNotificationUri()
open MutableList<Uri!>?	getNotificationUris()
Int	getPosition()
abstract Short	getShort(column: Int)
abstract String!	getString(column: Int)
open Int	getType(column: Int)
open Boolean	getWantsAllOnMoveCalls()
open CursorWindow!	getWindow() If the cursor is backed by a CursorWindow, returns a pre-filled window with the contents of the cursor, otherwise null.
Boolean	isAfterLast()
Boolean	isBeforeFirst()
open Boolean	isClosed()
Boolean	isFirst()
Boolean	isLast()
abstract Boolean	isNull(column: Int)
Boolean	move(offset: Int)
Boolean	moveToFirst()
Boolean	moveToLast()
Boolean	moveToNext()
Boolean	moveToPosition(position: Int)
Boolean	moveToPrevious()
open Boolean	onMove(oldPosition: Int, newPosition: Int) This function is called every time the cursor is successfully scrolled to a new position, giving the subclass a chance to update any state it may have.
open Unit	registerContentObserver(observer: ContentObserver!)
open Unit	registerDataSetObserver(observer: DataSetObserver!)
open Boolean	requery()
open Bundle!	respond(extras: Bundle!)
open Unit	setExtras(extras: Bundle!)
open Unit	setNotificationUri(cr: ContentResolver!, notifyUri: Uri!) Specifies a content URI to watch for changes.
open Unit	setNotificationUris(cr: ContentResolver, notifyUris: MutableList<Uri!>) Similar to setNotificationUri(android.content.ContentResolver,android.net.Uri), except this version allows to watch multiple content URIs for changes.
open Unit	unregisterContentObserver(observer: ContentObserver!)
open Unit	unregisterDataSetObserver(observer: DataSetObserver!)

Protected methods
open Unit	checkPosition() This function throws CursorIndexOutOfBoundsException if the cursor position is out of bounds.
open Unit	finalize()
open Any!	getUpdatedField(columnIndex: Int)
open Boolean	isFieldUpdated(columnIndex: Int)
open Unit	onChange(selfChange: Boolean) Subclasses must call this method when they finish committing updates to notify all observers.

Properties
Boolean	mClosed
ContentResolver!	mContentResolver
Int	mPos

Public constructors

AbstractCursor

AbstractCursor()

Public methods

close

open fun close(): Unit

Exceptions
java.lang.Exception	if this resource cannot be closed
java.io.IOException	if an I/O error occurs

copyStringToBuffer

open fun copyStringToBuffer(
columnIndex: Int,
buffer: CharArrayBuffer!
): Unit

Parameters
columnIndex	Int: the zero-based index of the target column. if the target column is null, return buffer Value is 0 or greater
buffer	CharArrayBuffer!: the buffer to copy the text into.

deactivate

open fun deactivate(): Unit

fillWindow

open fun fillWindow(
position: Int,
window: CursorWindow!
): Unit

Parameters
position	Int: The zero-based index of the first row to copy into the window.
window	CursorWindow!: The window to fill.

getBlob

open fun getBlob(column: Int): ByteArray!

Parameters
columnIndex	the zero-based index of the target column. Value is 0 or greater

Return
ByteArray!	the value of that column as a byte array.

getColumnCount

open fun getColumnCount(): Int

Return
Int	number of columns Value is 0 or greater

getColumnIndex

open fun getColumnIndex(columnName: String!): Int

Parameters
columnName	String!: the name of the target column.

Return
Int	the zero-based column index for the given column name, or -1 if the column name does not exist. Value is -1 or greater

getColumnIndexOrThrow

open fun getColumnIndexOrThrow(columnName: String!): Int

Parameters
columnName	String!: the name of the target column.

Return
Int	the zero-based column index for the given column name Value is 0 or greater

Exceptions
java.lang.IllegalArgumentException	if the column does not exist

getColumnName

open fun getColumnName(columnIndex: Int): String!

Parameters
columnIndex	Int: the zero-based index of the target column. Value is 0 or greater

Return
String!	the column name for the given column index.

getColumnNames

abstract fun getColumnNames(): Array<String!>!

Return
Array<String!>!	the names of the columns returned in this query.

getCount

abstract fun getCount(): Int

Return
Int	the number of rows in the cursor. Value is 0 or greater

getDouble

abstract fun getDouble(column: Int): Double

Parameters
columnIndex	the zero-based index of the target column. Value is 0 or greater

Return
Double	the value of that column as a double.

getFloat

abstract fun getFloat(column: Int): Float

Parameters
columnIndex	the zero-based index of the target column. Value is 0 or greater

Return
Float	the value of that column as a float.

getInt

abstract fun getInt(column: Int): Int

Parameters
columnIndex	the zero-based index of the target column. Value is 0 or greater

Return
Int	the value of that column as an int.

getLong

abstract fun getLong(column: Int): Long

Parameters
columnIndex	the zero-based index of the target column. Value is 0 or greater

Return
Long	the value of that column as a long.

getNotificationUri

open fun getNotificationUri(): Uri!

Return
Uri!	Returns a URI that can be used with ContentResolver.registerContentObserver to find out about changes to this Cursor's data. May be null if no notification URI has been set.

getPosition

fun getPosition(): Int

Return
Int	the current cursor position. Value is -1 or greater

getShort

abstract fun getShort(column: Int): Short

Parameters
columnIndex	the zero-based index of the target column. Value is 0 or greater

Return
Short	the value of that column as a short.

getString

abstract fun getString(column: Int): String!

Parameters
columnIndex	the zero-based index of the target column. Value is 0 or greater

Return
String!	the value of that column as a String.

getWantsAllOnMoveCalls

open fun getWantsAllOnMoveCalls(): Boolean

Return
Boolean	whether all cursor movement should result in a call to onMove().

getWindow

open fun getWindow(): CursorWindow!

If the cursor is backed by a [CursorWindow](/reference/kotlin/android/database/CursorWindow), returns a pre-filled window with the contents of the cursor, otherwise null.

Return
CursorWindow!	The pre-filled window that backs this cursor, or null if none.

isAfterLast

fun isAfterLast(): Boolean

Return
Boolean	whether the cursor is after the last result.

isBeforeFirst

fun isBeforeFirst(): Boolean

Return
Boolean	whether the cursor is before the first result.

isClosed

open fun isClosed(): Boolean

Return
Boolean	true if the cursor is closed.

isFirst

fun isFirst(): Boolean

Return
Boolean	whether the cursor is pointing at the first entry.

isLast

fun isLast(): Boolean

Return
Boolean	whether the cursor is pointing at the last entry.

isNull

abstract fun isNull(column: Int): Boolean

Parameters
columnIndex	the zero-based index of the target column. Value is 0 or greater

Return
Boolean	whether the column value is null.

move

fun move(offset: Int): Boolean

Parameters
offset	Int: the offset to be applied from the current position.

Return
Boolean	whether the requested move fully succeeded.

moveToFirst

fun moveToFirst(): Boolean

Return
Boolean	whether the move succeeded.

moveToLast

fun moveToLast(): Boolean

Return
Boolean	whether the move succeeded.

moveToNext

fun moveToNext(): Boolean

Return
Boolean	whether the move succeeded.

moveToPosition

fun moveToPosition(position: Int): Boolean

Parameters
position	Int: the zero-based position to move to. Value is -1 or greater

Return
Boolean	whether the requested move fully succeeded.

moveToPrevious

fun moveToPrevious(): Boolean

Return
Boolean	whether the move succeeded.

onMove

open fun onMove(
oldPosition: Int,
newPosition: Int
): Boolean

This function is called every time the cursor is successfully scrolled to a new position, giving the subclass a chance to update any state it may have. If it returns false the move function will also do so and the cursor will scroll to the beforeFirst position.

Parameters
oldPosition	Int: the position that we're moving from
newPosition	Int: the position that we're moving to

Return
Boolean	true if the move is successful, false otherwise

registerContentObserver

open fun registerContentObserver(observer: ContentObserver!): Unit

Parameters
observer	ContentObserver!: the object that gets notified when the content backing the cursor changes.

registerDataSetObserver

open fun registerDataSetObserver(observer: DataSetObserver!): Unit

Parameters
observer	DataSetObserver!: the object that gets notified when the cursors data set changes.

requery

open fun requery(): Boolean

Return
Boolean	true if the requery succeeded, false if not, in which case the cursor becomes invalid.

open fun setExtras(extras: Bundle!): Unit

Parameters
extras	Bundle!: Bundle to set, or null to set an empty bundle.

setNotificationUri

open fun setNotificationUri(
cr: ContentResolver!,
notifyUri: Uri!
): Unit

Specifies a content URI to watch for changes.

Parameters
cr	ContentResolver!: The content resolver from the caller's context.
uri	The content URI to watch.
notifyUri	Uri!: The URI to watch for changes. This can be a specific row URI, or a base URI for a whole class of content.

Protected methods

checkPosition

protected open fun checkPosition(): Unit

This function throws CursorIndexOutOfBoundsException if the cursor position is out of bounds. Subclass implementations of the get functions should call this before attempting to retrieve data.

Exceptions
android.database.CursorIndexOutOfBoundsException

finalize

protected open fun finalize(): Unit

Exceptions
java.lang.Throwable	the Exception raised by this method

getUpdatedField

protected open fun ~~getUpdatedField~~(columnIndex: Int): Any!

Deprecated: Always returns null since Cursors do not support updating rows

isFieldUpdated

protected open fun ~~isFieldUpdated~~(columnIndex: Int): Boolean

Deprecated: Always returns false since Cursors do not support updating rows

onChange

protected open fun onChange(selfChange: Boolean): Unit

Subclasses must call this method when they finish committing updates to notify all observers.

Parameters
selfChange	Boolean:

Properties

mClosed

protected var ~~mClosed~~: Boolean

Deprecated: Use [isClosed()](#isClosed%28%29) instead.

mContentResolver

protected var ~~mContentResolver~~: ContentResolver!

Deprecated: Do not use.

mPos

protected var ~~mPos~~: Int

Deprecated: Use [getPosition()](#getPosition%28%29) instead.