CursorWrapper

Kotlin |Java

open class CursorWrapper : Cursor

kotlin.Any
↳	android.database.CursorWrapper

Known Direct Subclasses

CrossProcessCursorWrapper

Cursor wrapper that implements CrossProcessCursor.

Wrapper class for Cursor that delegates all calls to the actual cursor object. The primary use for this class is to extend a cursor while overriding only a subset of its methods.

Summary

Inherited constants

From class Cursor

`Int`	`FIELD_TYPE_BLOB` Value returned by `getType(int)` if the specified column type is blob
`Int`	`FIELD_TYPE_FLOAT` Value returned by `getType(int)` if the specified column type is float
`Int`	`FIELD_TYPE_INTEGER` Value returned by `getType(int)` if the specified column type is integer
`Int`	`FIELD_TYPE_NULL` Value returned by `getType(int)` if the specified column is null
`Int`	`FIELD_TYPE_STRING` Value returned by `getType(int)` if the specified column type is string

Public constructors
`CursorWrapper(cursor: Cursor!)` Creates a cursor wrapper.

Public methods
open Unit	`close()` Closes the Cursor, releasing all of its resources and making it completely invalid.
open Unit	`copyStringToBuffer(columnIndex: Int, buffer: CharArrayBuffer!)` Retrieves the requested column text and stores it in the buffer provided.
open Unit	`deactivate()` Deactivates the Cursor, making all calls on it fail until `requery` is called.
open ByteArray!	`getBlob(columnIndex: Int)` Returns the value of the requested column as a byte array.
open Int	`getColumnCount()` Return total number of columns
open Int	`getColumnIndex(columnName: String!)` Returns the zero-based index for the given column name, or -1 if the column doesn't exist.
open Int	`getColumnIndexOrThrow(columnName: String!)` Returns the zero-based index for the given column name, or throws `IllegalArgumentException` if the column doesn't exist.
open String!	`getColumnName(columnIndex: Int)` Returns the column name at the given zero-based column index.
open Array<String!>!	`getColumnNames()` Returns a string array holding the names of all of the columns in the result set in the order in which they were listed in the result.
open Int	`getCount()` Returns the numbers of rows in the cursor.
open Double	`getDouble(columnIndex: Int)` Returns the value of the requested column as a double.
open Bundle!	`getExtras()` Returns a bundle of extra values.
open Float	`getFloat(columnIndex: Int)` Returns the value of the requested column as a float.
open Int	`getInt(columnIndex: Int)` Returns the value of the requested column as an int.
open Long	`getLong(columnIndex: Int)` Returns the value of the requested column as a long.
open Uri!	`getNotificationUri()` Return the URI at which notifications of changes in this Cursor's data will be delivered, as previously set by `setNotificationUri`.
open MutableList<Uri!>?	`getNotificationUris()` Return the URIs at which notifications of changes in this Cursor's data will be delivered, as previously set by `setNotificationUris`.
open Int	`getPosition()` Returns the current position of the cursor in the row set.
open Short	`getShort(columnIndex: Int)` Returns the value of the requested column as a short.
open String!	`getString(columnIndex: Int)` Returns the value of the requested column as a String.
open Int	`getType(columnIndex: Int)` Returns data type of the given column's value.
open Boolean	`getWantsAllOnMoveCalls()` onMove() will only be called across processes if this method returns true.
open Cursor!	`getWrappedCursor()` Gets the underlying cursor that is wrapped by this instance.
open Boolean	`isAfterLast()` Returns whether the cursor is pointing to the position after the last row.
open Boolean	`isBeforeFirst()` Returns whether the cursor is pointing to the position before the first row.
open Boolean	`isClosed()` return true if the cursor is closed
open Boolean	`isFirst()` Returns whether the cursor is pointing to the first row.
open Boolean	`isLast()` Returns whether the cursor is pointing to the last row.
open Boolean	`isNull(columnIndex: Int)` Returns `true` if the value in the indicated column is null.
open Boolean	`move(offset: Int)` Move the cursor by a relative amount, forward or backward, from the current position.
open Boolean	`moveToFirst()` Move the cursor to the first row.
open Boolean	`moveToLast()` Move the cursor to the last row.
open Boolean	`moveToNext()` Move the cursor to the next row.
open Boolean	`moveToPosition(position: Int)` Move the cursor to an absolute position.
open Boolean	`moveToPrevious()` Move the cursor to the previous row.
open Unit	`registerContentObserver(observer: ContentObserver!)` Register an observer that is called when changes happen to the content backing this cursor.
open Unit	`registerDataSetObserver(observer: DataSetObserver!)` Register an observer that is called when changes happen to the contents of the this cursors data set, for example, when the data set is changed via `requery()`, `deactivate()`, or #close().
open Boolean	`requery()` Performs the query that created the cursor again, refreshing its contents.
open Bundle!	`respond(extras: Bundle!)` This is an out-of-band way for the user of a cursor to communicate with the cursor.
open Unit	`setExtras(extras: Bundle!)` Sets a `Bundle` that will be returned by `getExtras()`.
open Unit	`setNotificationUri(cr: ContentResolver!, uri: Uri!)` Register to watch a content URI for changes.
open Unit	`setNotificationUris(cr: ContentResolver, uris: 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!)` Unregister an observer that has previously been registered with this cursor via `registerContentObserver`.
open Unit	`unregisterDataSetObserver(observer: DataSetObserver!)` Unregister an observer that has previously been registered with this cursor via `registerContentObserver`.

Public constructors

CursorWrapper

Added in API level 1

CursorWrapper(cursor: Cursor!)

Creates a cursor wrapper.

Parameters
`cursor`	Cursor!: The underlying cursor to wrap.

Public methods

close

Added in API level 1

open fun close(): Unit

Closes the Cursor, releasing all of its resources and making it completely invalid. Unlike deactivate() a call to requery() will not make the Cursor valid again.

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

copyStringToBuffer

Added in API level 1

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

Retrieves the requested column text and stores it in the buffer provided. If the buffer size is not sufficient, a new char buffer will be allocated and assigned to CharArrayBuffer.data

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

Added in API level 1

open fun deactivate(): Unit

Deprecated: Deprecated in Java.

Deactivates the Cursor, making all calls on it fail until requery is called. Inactive Cursors use fewer resources than active Cursors. Calling requery will make the cursor active again.

getBlob

Added in API level 1

open fun getBlob(columnIndex: Int): ByteArray!

Returns the value of the requested column as a byte array.

The result and whether this method throws an exception when the column value is null or the column type is not a blob type is implementation-defined.

Parameters
`columnIndex`	Int: 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

Added in API level 1

open fun getColumnCount(): Int

Return total number of columns

Return
`Int`	number of columns. Value is 0 or greater

getColumnIndex

Added in API level 1

open fun getColumnIndex(columnName: String!): Int

Returns the zero-based index for the given column name, or -1 if the column doesn't exist. If you expect the column to exist use getColumnIndexOrThrow(java.lang.String) instead, which will make the error more clear.

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

Added in API level 1

open fun getColumnIndexOrThrow(columnName: String!): Int

Returns the zero-based index for the given column name, or throws IllegalArgumentException if the column doesn't exist. If you're not sure if a column will exist or not use getColumnIndex(java.lang.String) and check for -1, which is more efficient than catching the exceptions.

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

Added in API level 1

open fun getColumnName(columnIndex: Int): String!

Returns the column name at the given zero-based column index.

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

Added in API level 1

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

Returns a string array holding the names of all of the columns in the result set in the order in which they were listed in the result.

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

getCount

Added in API level 1

open fun getCount(): Int

Returns the numbers of rows in the cursor.

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

getDouble

Added in API level 1

open fun getDouble(columnIndex: Int): Double

Returns the value of the requested column as a double.

The result and whether this method throws an exception when the column value is null, the column type is not a floating-point type, or the floating-point value is not representable as a double value is implementation-defined.

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

Return
`Double`	the value of that column as a double.

getExtras

Added in API level 1

open fun getExtras(): Bundle!

Returns a bundle of extra values. This is an optional way for cursors to provide out-of-band metadata to their users. One use of this is for reporting on the progress of network requests that are required to fetch data for the cursor.

These values may only change when requery is called.

Return
`Bundle!`	cursor-defined values, or `Bundle.EMPTY` if there are no values. Never `null`.

getFloat

Added in API level 1

open fun getFloat(columnIndex: Int): Float

Returns the value of the requested column as a float.

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

Return
`Float`	the value of that column as a float.

getInt

Added in API level 1

open fun getInt(columnIndex: Int): Int

Returns the value of the requested column as an int.

The result and whether this method throws an exception when the column value is null, the column type is not an integral type, or the integer value is outside the range [Integer.MIN_VALUE, Integer.MAX_VALUE] is implementation-defined.

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

Return
`Int`	the value of that column as an int.

getLong

Added in API level 1

open fun getLong(columnIndex: Int): Long

Returns the value of the requested column as a long.

The result and whether this method throws an exception when the column value is null, the column type is not an integral type, or the integer value is outside the range [Long.MIN_VALUE, Long.MAX_VALUE] is implementation-defined.

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

Return
`Long`	the value of that column as a long.

getNotificationUri

Added in API level 19

open fun getNotificationUri(): Uri!

Return the URI at which notifications of changes in this Cursor's data will be delivered, as previously set by setNotificationUri.

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.

getNotificationUris

Added in API level 29

open fun getNotificationUris(): MutableList<Uri!>?

Return the URIs at which notifications of changes in this Cursor's data will be delivered, as previously set by setNotificationUris.

If this is not implemented, this is equivalent to calling getNotificationUri().

Return
`MutableList<Uri!>?`	Returns URIs 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

Added in API level 1

open fun getPosition(): Int

Returns the current position of the cursor in the row set. The value is zero-based. When the row set is first returned the cursor will be at positon -1, which is before the first row. After the last row is returned another call to next() will leave the cursor past the last entry, at a position of count().

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

getShort

Added in API level 1

open fun getShort(columnIndex: Int): Short

Returns the value of the requested column as a short.

The result and whether this method throws an exception when the column value is null, the column type is not an integral type, or the integer value is outside the range [Short.MIN_VALUE, Short.MAX_VALUE] is implementation-defined.

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

Return
`Short`	the value of that column as a short.

getString

Added in API level 1

open fun getString(columnIndex: Int): String!

Returns the value of the requested column as a String.

The result and whether this method throws an exception when the column value is null or the column type is not a string type is implementation-defined.

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

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

getType

Added in API level 11

open fun getType(columnIndex: Int): Int

Returns data type of the given column's value. The preferred type of the column is returned but the data may be converted to other types as documented in the get-type methods such as getInt(int), getFloat(int) etc.

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

Return
`Int`	column value type. Value is one of the following: `FIELD_TYPE_NULL` `FIELD_TYPE_INTEGER` `FIELD_TYPE_FLOAT` `FIELD_TYPE_STRING` `FIELD_TYPE_BLOB`

getWantsAllOnMoveCalls

Added in API level 1

open fun getWantsAllOnMoveCalls(): Boolean

onMove() will only be called across processes if this method returns true.

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

getWrappedCursor

Added in API level 11

open fun getWrappedCursor(): Cursor!

Gets the underlying cursor that is wrapped by this instance.

Return
`Cursor!`	The wrapped cursor.

isAfterLast

Added in API level 1

open fun isAfterLast(): Boolean

Returns whether the cursor is pointing to the position after the last row.

Return
`Boolean`	whether the cursor is after the last result.

isBeforeFirst

Added in API level 1

open fun isBeforeFirst(): Boolean

Returns whether the cursor is pointing to the position before the first row.

Return
`Boolean`	whether the cursor is before the first result.

isClosed

Added in API level 1

open fun isClosed(): Boolean

return true if the cursor is closed

Return
`Boolean`	true if the cursor is closed.

isFirst

Added in API level 1

open fun isFirst(): Boolean

Returns whether the cursor is pointing to the first row.

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

isLast

Added in API level 1

open fun isLast(): Boolean

Returns whether the cursor is pointing to the last row.

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

isNull

Added in API level 1

open fun isNull(columnIndex: Int): Boolean

Returns true if the value in the indicated column is null.

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

Return
`Boolean`	whether the column value is null.

move

Added in API level 1

open fun move(offset: Int): Boolean

Move the cursor by a relative amount, forward or backward, from the current position. Positive offsets move forwards, negative offsets move backwards. If the final position is outside of the bounds of the result set then the resultant position will be pinned to -1 or count() depending on whether the value is off the front or end of the set, respectively.

This method will return true if the requested destination was reachable, otherwise, it returns false. For example, if the cursor is at currently on the second entry in the result set and move(-5) is called, the position will be pinned at -1, and false will be returned.

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

Return
`Boolean`	whether the requested move fully succeeded.

moveToFirst

Added in API level 1

open fun moveToFirst(): Boolean

Move the cursor to the first row.

This method will return false if the cursor is empty.

Return
`Boolean`	whether the move succeeded.

moveToLast

Added in API level 1

open fun moveToLast(): Boolean

Move the cursor to the last row.

This method will return false if the cursor is empty.

Return
`Boolean`	whether the move succeeded.

moveToNext

Added in API level 1

open fun moveToNext(): Boolean

Move the cursor to the next row.

This method will return false if the cursor is already past the last entry in the result set.

Return
`Boolean`	whether the move succeeded.

moveToPosition

Added in API level 1

open fun moveToPosition(position: Int): Boolean

Move the cursor to an absolute position. The valid range of values is -1 <= position <= count.

This method will return true if the request destination was reachable, otherwise, it returns false.

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

Return
`Boolean`	whether the requested move fully succeeded.

moveToPrevious

Added in API level 1

open fun moveToPrevious(): Boolean

Move the cursor to the previous row.

This method will return false if the cursor is already before the first entry in the result set.

Return
`Boolean`	whether the move succeeded.

registerContentObserver

Added in API level 1

open fun registerContentObserver(observer: ContentObserver!): Unit

Register an observer that is called when changes happen to the content backing this cursor. Typically the data set won't change until requery() is called.

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

registerDataSetObserver

Added in API level 1

open fun registerDataSetObserver(observer: DataSetObserver!): Unit

Register an observer that is called when changes happen to the contents of the this cursors data set, for example, when the data set is changed via requery(), deactivate(), or #close().

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

requery

Added in API level 1

open fun requery(): Boolean

Deprecated: Deprecated in Java.

Performs the query that created the cursor again, refreshing its contents. This may be done at any time, including after a call to deactivate. Since this method could execute a query on the database and potentially take a while, it could cause ANR if it is called on Main (UI) thread. A warning is printed if this method is being executed on Main thread.

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

respond

Added in API level 1

open fun respond(extras: Bundle!): Bundle!

This is an out-of-band way for the user of a cursor to communicate with the cursor. The structure of each bundle is entirely defined by the cursor.

One use of this is to tell a cursor that it should retry its network request after it reported an error.

Parameters
`extras`	Bundle!: extra values, or `Bundle.EMPTY`. Never `null`.

Return
`Bundle!`	extra values, or `Bundle.EMPTY`. Never `null`.

setExtras

Added in API level 23

open fun setExtras(extras: Bundle!): Unit

Sets a Bundle that will be returned by getExtras().

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

setNotificationUri

Added in API level 1

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

Register to watch a content URI for changes. This can be the URI of a specific data row (for example, "content://my_provider_type/23"), or a a generic URI for a content type.

Calling this overrides any previous call to setNotificationUris(android.content.ContentResolver,java.util.List).

Parameters
`cr`	ContentResolver!: The content resolver from the caller's context. The listener attached to this resolver will be notified.
`uri`	Uri!: The content URI to watch.

setNotificationUris

Added in API level 29

open fun setNotificationUris(
    cr: ContentResolver, 
    uris: MutableList<Uri!>
): Unit

Similar to setNotificationUri(android.content.ContentResolver,android.net.Uri), except this version allows to watch multiple content URIs for changes.

If this is not implemented, this is equivalent to calling setNotificationUri(android.content.ContentResolver,android.net.Uri) with the first URI in uris.

Calling this overrides any previous call to setNotificationUri(android.content.ContentResolver,android.net.Uri).

Parameters
`cr`	ContentResolver: The content resolver from the caller's context. The listener attached to this resolver will be notified. This value cannot be `null`.
`uris`	MutableList<Uri!>: The content URIs to watch. This value cannot be `null`.

unregisterContentObserver

Added in API level 1

open fun unregisterContentObserver(observer: ContentObserver!): Unit

Unregister an observer that has previously been registered with this cursor via registerContentObserver.

Parameters
`observer`	ContentObserver!: the object to unregister.

unregisterDataSetObserver

Added in API level 1

open fun unregisterDataSetObserver(observer: DataSetObserver!): Unit

Unregister an observer that has previously been registered with this cursor via registerContentObserver.

Parameters
`observer`	DataSetObserver!: the object to unregister.