Question

我是Objective C编程的初学者，过去几天我一直在努力解决这个问题。我有一个名为tasks的NSMutableArray，我在switch语句中访问它来改变这样的开关案例

- (IBAction)random:(id)sender { int text = [[self.tasks objectAtIndex:x] intValue]; x++;

完美无瑕。但是当我尝试通过其中一种方法随机化/改组任务数组时，它只显示case 0的{{1}}。我希望能够使用新洗牌的数组来更改开关案例。我是在正确的轨道上还是这样的话甚至可能？

ViewController.m

switch

ViewController.h

//
//  ViewController.m


#import "ViewController.h"
#import "AudioToolbox/AudioToolbox.h"
#import <GameKit/GameKit.h>
#import "NSMutableArray_Shuffling.h"

@import GameKit;

@interface ViewController ()


@end

@implementation ViewController

- (void)viewDidLoad {

    [self.navigationController.navigationBar setBackgroundImage:[UIImage imageNamed:@"navback.png"] forBarMetrics:UIBarMetricsDefault];

    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}






-(NSMutableArray*) tasks {
    tasks = [[NSMutableArray alloc]initWithObjects:[NSNumber numberWithInteger:0] ,[NSNumber numberWithInteger:1] ,[NSNumber numberWithInteger:2] ,[NSNumber numberWithInteger:3] ,[NSNumber numberWithInteger:4] ,[NSNumber numberWithInteger:5] ,[NSNumber numberWithInteger:6] ,[NSNumber numberWithInteger:7] ,[NSNumber numberWithInteger:8] ,[NSNumber numberWithInteger:9] ,[NSNumber numberWithInteger:10] ,[NSNumber numberWithInteger:11] ,[NSNumber numberWithInteger:12] ,[NSNumber numberWithInteger:13] ,[NSNumber numberWithInteger:14] ,[NSNumber numberWithInteger:15] ,[NSNumber numberWithInteger:16] ,[NSNumber numberWithInteger:17] ,[NSNumber numberWithInteger:18] ,[NSNumber numberWithInteger:19] ,[NSNumber numberWithInteger:20] ,[NSNumber numberWithInteger:21] ,[NSNumber numberWithInteger:22], nil];

    return tasks;
}

int x=0;
int z=9999;
int k=0;

//Neither of these shuffle methods work.

/*
 - (void)shuffle
 {
 NSUInteger count = [tasks count];
 if (count < 1) return;
 for (NSUInteger i = 0; i < count - 1; ++i) {
 NSInteger remainingCount = count - i;
 NSInteger exchangeIndex = i + arc4random_uniform((u_int32_t )remainingCount);
 [tasks exchangeObjectAtIndex:i withObjectAtIndex:exchangeIndex];
 }
 }

 -(void)shuffle
 {
 shuffledTasks = [[GKRandomSource sharedRandom] arrayByShufflingObjectsInArray:tasks];

 }

 */


// This is for checking if x is > than the number of elements in my tasks array, then reseting it and shuffling the array so a new order of elements is presented for the switch. But it works only for reseting the x.
-(void)reset{
    if (x>22) {
        x=0;
        [self shuffle];



    }
}

//The switch, which currently only pulls objectAtIndex:x from the original tasks array. No matter how I try to shuffle it.

- (IBAction)random:(id)sender {
    int text = [[self.tasks objectAtIndex:x] intValue];
    x++;


    switch (text) {

        case 0:
            z=0;
            //something magical will happen
            [self reset];
            break;

        case 1:
            z=1;
            //something magical will happen
            [self reset];
            break;

        case 2:
            z=2;
            //something magical will happen
            [self reset];
            break;

        case 3:
            z=3;
            //something magical will happen
            [self reset];
            break;

        case 4:
            z=4;
            //something magical will happen
            [self reset];
            break;

//cases 5-21…

        case 22:
            z=22;
            //something magical will happen
            [self reset];
            break;


        default:
            z=9999;


    }
}



- (void)dealloc {
    [super dealloc];
}
@end

Answer 1

你在哪里设置x的值？无论哪种方式添加此行

int x = arc4random_uniform(self.tasks - 1);

高于这个

int text = [[self.tasks objectAtIndex:x] intValue];

并且它应该完美地工作（假设self.tasks中的元素是＆＃34;值类型＆＃34;否则你将在这里得到零：

int text = [[self.tasks objectAtIndex:x] intValue];

改组NSArray并使用混洗阵列来改变开关盒。目标C

1 个答案: