Legacy Document
Important: The information in this document is obsolete and should not be used for new development.
NSSortDescriptor
| Inherits from | |
| Implements | |
| Package | com.apple.cocoa.foundation |
| Availability | Available in Mac OS X v10.3 and later. |
| Companion guide |
Overview
NSSortDescriptor describes how an array of objects should be sorted. Objects of this class do not actually sort the array, the sort methods are defined as a category on NSArray and NSMutableArray. Instances of NSSortDescriptor are immutable.
You construct objects of this class by specifying the property key to be compared, the order of the sort (ascending or descending), and a selector that is used to perform the comparison. If null, the selector parameter defaults to the selector compare. The three-argument constructor allows you to specify other comparison selectors such as caseInsensitiveCompare and localizedCompare. Sorting throws an exception if the objects to be sorted do not respond to the sort descriptor’s comparison selector.
Tasks
Constructors
Getting Information About a Sort Descriptor
Using Sort Descriptors
Constructors
NSSortDescriptor
Creates and returns an empty NSSortDescriptor.
public NSSortDescriptor()
Availability
- Available in Mac OS X v10.3 and later.
Creates and returns an NSSortDescriptor with the property key specified by key, sort order specified by ascending, and the default selector compare.
public NSSortDescriptor(String key, boolean ascending)
Availability
- Available in Mac OS X v10.3 and later.
Creates and returns an NSSortDescriptor with the property key specified by key, sort order specified by ascending, and the selector specified by selector.
public NSSortDescriptor(String key, boolean ascending, NSSelector selector)
Availability
- Available in Mac OS X v10.3 and later.
Instance Methods
ascending
Returns a Boolean value that indicates whether the receiver will sort items in ascending order.
public boolean ascending()
Availability
- Available in Mac OS X v10.3 and later.
compareObjects
public int compareObjects(Object object1, Object object2)
Discussion
Compares object1 with object2, using the selector specified by the receiver. Returns OrderedAscending if object1 is less than object2, OrderedDescending if object1 is greater than object2, or OrderedSame if object1 is equal to object2.
Availability
- Available in Mac OS X v10.3 and later.
key
Returns the receiver’s property key.
public String key()
Discussion
This key specifies the property that is compared during sorting.
Availability
- Available in Mac OS X v10.3 and later.
reversedSortDescriptor
Returns a copy of the receiver with the sort order reversed.
public Object reversedSortDescriptor()
Availability
- Available in Mac OS X v10.3 and later.
selector
Returns the selector the receiver will use when comparing objects.
public NSSelector selector()
Availability
- Available in Mac OS X v10.3 and later.
© 1997, 2006 Apple Computer, Inc. All Rights Reserved. (Last updated: 2006-07-24)