我的应用程序中有飞行搜索功能,这需要很长时间才能获得数据(超过25秒).如果应用程序进入后台或进入睡眠模式,则互联网连接断开连接.
我已经使用苹果示例编写了下面的逻辑来使api请求继续进行,即使应用程序转到后台但它不起作用.
self.session = [self backgroundSession];
self.mutableData = [NSMutableData data];
NSURL *downloadURL = [NSURL URLWithString:@"http://jsonplaceholder.typicode.com/photos"];
NSURLRequest *request = [NSURLRequest requestWithURL:downloadURL];
self.dataTask = [self.session dataTaskWithRequest:request];
[self.dataTask resume];
- (NSURLSession *)backgroundSession
{
static NSURLSession *session = nil;
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration backgroundSessionConfigurationWithIdentifier:@"com.example.apple-samplecode.SimpleBackgroundTransfer.BackgroundSession"];
session = [NSURLSession sessionWithConfiguration:configuration delegate:self delegateQueue:nil];
});
return session;
}
Run Code Online (Sandbox Code Playgroud)
以下是委托方法
- (void)URLSession:(NSURLSession *)session dataTask:(NSURLSessionDataTask *)dataTask
didReceiveResponse:(NSURLResponse *)response
completionHandler:(void (^)(NSURLSessionResponseDisposition disposition))completionHandler {
NSLog(@"response: %@", response.debugDescription);
NSURLSessionResponseDisposition disposition = NSURLSessionResponseAllow;
if (completionHandler) {
completionHandler(disposition);
}
} …Run Code Online (Sandbox Code Playgroud)