Question

我想要从目录中显示图像。在目录中，我已经创建了用于存储图片的文件夹。我收到的错误是使用未声明的标识符'NSFileManagerdefaultManager'和使用未声明的标识符'documentsDirectory';你是说'NSDocumentDirectory'吗？和坏接收器类型'NSUInteger'（又名'unsigned int'）。我无法摆脱这一点。我正在尝试，但它只是不起作用。

-(void)viewDidLoad
{
    [super viewDidLoad];

    //configure carousel
    imageArray1 = (NSMutableArray *)[[NSFileManager defaultManager] directoryContentsAtPath: fPath];
    NSString *location=@"Tops";
    NSString *fPath = [documentsDirectory stringByAppendingPathComponent:location];
    NSArray *directoryContent = [[NSFileManager defaultManager] directoryContentsAtPath: fPath];
    imageArray1 = [directoryContent mutableCopy];

    imageArray2 = [[NSMutableArray alloc] init];
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsDirectory = [paths objectAtIndex:0];
    location=@"Bottoms";
    fPath = [documentsDirectory stringByAppendingPathComponent:location];

    directoryContent = [[NSFileManager defaultManager] directoryContentsAtPath: fPath];
    imageArray2 = [directoryContent mutableCopy];

    carousel1.type = iCarouselTypeLinear;
    carousel2.type = iCarouselTypeLinear;
}

Answer 1

您的代码中有一些非常奇怪的东西：

imageArray1 = (NSMutableArray *)[[NSFileManager defaultManager] directoryContentsAtPath: fPath];

在这里，您要向NSArray投射NSMutableArray，但它仍然是NSArray。你不能这样做。

NSString *location=@"Tops";
NSString *fPath = [documentsDirectory stringByAppendingPathComponent:location];
NSArray *directoryContent = [[NSFileManager defaultManager] directoryContentsAtPath: fPath];
imageArray1 = [directoryContent mutableCopy];

然后构建fpath字符串，您已经在第一行使用了该字符串。您正在进行正确转换为NSMutableArray。

你只需要删除第一行，它不是必需的，什么都不做。这条线也是如此：

imageArray2 = [[NSMutableArray alloc] init];

您只需创建一个空数组，然后再分配另一个数组：

imageArray2 = [directoryContent mutableCopy];

只需删除imageArray2 = [[NSMutableArray alloc] init];即可，只会使用不必要的内存。

这会更好用：

-(void)viewDidLoad
{
    [super viewDidLoad];

    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsDirectory = [paths objectAtIndex:0];
    NSFileManager *fileManager  = [NSFileManager defaultManager];

    //configure carousel
    NSString *fPath = [documentsDirectory stringByAppendingPathComponent:@"Tops"];
    NSArray *directoryContent = [fileManager directoryContentsAtPath: fPath];
    imageArray1 = [directoryContent mutableCopy];

    //configure carouse2
    fPath = [documentsDirectory stringByAppendingPathComponent:@"Bottoms";];
    directoryContent = [fileManager directoryContentsAtPath:fPath];
    imageArray2 = [directoryContent mutableCopy];

    carousel1.type = iCarouselTypeLinear;
    carousel2.type = iCarouselTypeLinear;
}

使用iCarousel显示目录中的图像

1 个答案: