Credit where credit is due: This is MichaelMeer’s original MMRandomEnumerator class

MMRandomEnumerator.h

// MMRandomEnumerator.h // XQuizIt

// Created by Michael Meer on Thu Oct 31 2002. // Copyright (c) 2002 Michael Meer. All rights reserved.

#import <Cocoa/Cocoa.h>

@interface MMRandomEnumerator: NSObject { NSMutableArray *array; int currentIndex; }

#pragma mark ��� INITIALIZATION ���

• ( id ) initWithArray: ( NSArray * ) newArray;
• ( id ) nextObject;
• ( int ) count;

#pragma mark ��� ACCESSORS ���

• ( void ) setArray: ( NSMutableArray * ) newArray;
• ( NSArray * ) array;
• ( int ) currentIndex;

@end

MMRandomEnumerator.m:

// MMRandomEnumerator.m // Shuffle the order of table entries or other array

// Created by Michael Meer on Thu Oct 31 2002. // Copyright (c) 2002 Michael Meer. All rights reserved.

#import “MMRandomEnumerator.h”

@implementation MMRandomEnumerator

#pragma mark ��� INITIALIZATION ���

• ( id ) init { if ( self = [ super init ] ) { array = [ [ NSMutableArray alloc ] init ]; currentIndex = 0; } return self; }

• ( id ) initWithArray: ( NSArray * ) newArray { MMRandomEnumerator *enumerator; NSMutableArray *newArrayCopy; NSMutableArray *resultArray; int arrayCount; int index;

  arrayCount = [ newArray count ]; enumerator = [ [ MMRandomEnumerator alloc ] init ]; newArrayCopy = [ NSMutableArray arrayWithArray: newArray ]; resultArray = [ NSMutableArray arrayWithCapacity: arrayCount ];

  while ( [ resultArray count ] < arrayCount ) { index = random( ) % [ newArrayCopy count ]; [ resultArray addObject: [ newArrayCopy objectAtIndex: index ] ]; [ newArrayCopy removeObjectAtIndex: index ]; }

  [ enumerator setArray: resultArray ];

  return [ enumerator autorelease ]; }

• ( void ) dealloc { [ array release ]; [ super dealloc ]; }

• ( id ) nextObject { if ( currentIndex >= [ array count ] ) { return nil; } else { return [ array objectAtIndex: currentIndex++ ]; } }

• ( int ) count { return [ array count ]; }

#pragma mark ��� ACCESSORS ���

• ( void ) setArray: ( NSMutableArray * ) newArray { [ array autorelease ]; array = [ newArray retain ]; }

• ( NSArray * ) array { return array; }

• ( int ) currentIndex { return currentIndex; }

@end