无法识别的选择器发送到实例

Question

我遇到了一个问题,即使在读完几个帖子后我也听不懂

这是我得到的错误:

*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[UIImage length]: unrecognized selector sent to instance 0x576f8f0'

这是代码:

- (void)viewDidLoad {
    [super viewDidLoad];

    NSString *filePath = [[self documentsPath] stringByAppendingPathComponent:@""];

    NSFileManager *imagesFileManager = [NSFileManager defaultManager];

    imagesArr = [[imagesFileManager contentsOfDirectoryAtPath:filePath error:nil]filteredArrayUsingPredicate:[NSPredicate predicateWithFormat:@"self ENDSWITH '.jpg'"]];

    arryList = [[NSMutableArray alloc] initWithArray:[imagesArr copy]];//display text
    imagesList = [[NSMutableArray alloc]init];//display image

    NSString *docPath = [self documentsPath];

    for (NSString *anImagePath in arryList) {
        anImagePath = [NSString stringWithFormat:@"%@/%@",docPath,anImagePath];
        UIImage *image = [UIImage imageWithContentsOfFile:anImagePath];
        if (image)
            [imagesList addObject:image];

        NSLog(@"%@", anImagePath);
    }
}   

Answer 1

你不是那个呼唤lengtha的人UIImage,forin循环是.这是因为对象arrayList实际上是图像,但是循环认为它们是字符串,因为你基本上用这种方式对它们进行了类型化NSString *anImagePath.尝试更改您的代码:

for (NSString *anImagePath in arryList) {
    anImagePath = [NSString stringWithFormat:@"%@/%@",docPath,anImagePath];
    UIImage *image = [UIImage imageWithContentsOfFile:anImagePath];
    if (image)
        [imagesList addObject:image];

    NSLog(@"%@", anImagePath);
}

对此:

for (UIImage *image in arryList) {
    if (image)
        [imagesList addObject:image];

    NSLog(@"%@", anImagePath);
}

我猜你已经UIImage在数组中存储了对象.有关更多参考,请访问尝试显示图像数组,代码将iphone返回到主屏幕.