ios - setImageWithURL AFNetworking 成功处理程序的问题

Question

在我的 UIImage 对象上调用 setImageWithURLRequest: 时，成功或失败处理程序似乎都不会被调用。 SetImageWithURL 也没有设置我的图像。如果我使用 setImageWithURL: placeholder: 占位符已设置，但 url 中的图像永远不会设置。

请原谅我没有早点发布代码。我尝试使用两种方法(使用 AFNetworking)来异步设置我的 ImageView :

[_imageView setImageWithURL:[NSURL URLWithString:@"path/to/file"]];

[_imageView setImageWithURLRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:@"http://www.example.com/path/to/image.jpg"]] placeholderImage:[UIImage imageNamed:@"your_image_here.jpg"] success:^(NSURLRequest *request, NSHTTPURLResponse *response, UIImage *image) {
NSLog(@"Your image request succeeded!");
} failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error) {
NSLog(@"Your image request failed...");
}];

我尝试在 viewDidLoad 中触发这些，但 ImageView 从未加载。

查看了 setImageWithURLRequest: 的实际函数声明后，当我调用它时，似乎成功或失败 block 都没有被执行。我在代码中放置了 NSLogs ，让大家了解会发生什么:

- (void)setImageWithURLRequest:(NSURLRequest *)urlRequest 
      placeholderImage:(UIImage *)placeholderImage 
               success:(void (^)(NSURLRequest *request, NSHTTPURLResponse *response, UIImage *image))success
               failure:(void (^)(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error))failure
{
NSLog(@"Log shows");

[self cancelImageRequestOperation];

NSLog(@"Log shows");
UIImage *cachedImage = [[[self class] af_sharedImageCache] cachedImageForRequest:urlRequest];

NSLog(@"Log shows");

if (cachedImage) {
NSLog(@"Log does not show");

self.image = cachedImage;
self.af_imageRequestOperation = nil;

if (success) {
    success(nil, nil, cachedImage);
    NSLog(@"Log does not show");

}
} else {
NSLog(@"Log shows");

self.image = placeholderImage;

AFImageRequestOperation *requestOperation = [[AFImageRequestOperation alloc] initWithRequest:urlRequest];
[requestOperation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
    if ([[urlRequest URL] isEqual:[[self.af_imageRequestOperation request] URL]]) {
        self.image = responseObject;
        self.af_imageRequestOperation = nil;
        NSLog(@"Log does not show");
    }

    if (success) {
        success(operation.request, operation.response, responseObject);
        NSLog(@"Log does not show");
    }

    [[[self class] af_sharedImageCache] cacheImage:responseObject forRequest:urlRequest];


} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
    if ([[urlRequest URL] isEqual:[[self.af_imageRequestOperation request] URL]]) {
        self.af_imageRequestOperation = nil;
        NSLog(@"Log does not show");
    }

    if (failure) {
        failure(operation.request, operation.response, error);
        NSLog(@"Log does not show");
    }

}];

self.af_imageRequestOperation = requestOperation;

[[[self class] af_sharedImageRequestOperationQueue] addOperation:self.af_imageRequestOperation];

Answer 1

setImageWithURL: 是一个 UIImageView 类别，不能用于设置仅在 UIImageView 上使用的 UIImage。

[imageView setImageWithURL:url placeholderImage:[UIImage imageNamed:@"placeHolderImage"]];

这是文档:http://engineering.gowalla.com/AFNetworking/Categories/UIImageView(AFNetworking).html