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我已經查看了所有問題的答案，並且看到了很多類似的問題，但解決方案似乎與我的情況無關。我對iOS開發非常陌生，所以不勝感激。後續的NSURLConnections不會觸發委託方法
目前的應用程序正在尋找基於他們的網站生成的XML提要顯示城市中發生的事件。我將事件存儲在plist中，並在應用程序加載時明確檢查新事件。目前的過程如下：
- 應用程序啓動並使NSURLConnection檢查服務器的時間戳並下載它。
- 檢查新下載的時間戳與本地時間戳，看看它是否更大。如果是，它會重寫包含plist的文件並觸發一個需要新事件的通知。
這是第二個NSURLConnection似乎沒有觸發的地方。回調方法本身觸發，但它似乎不像委託方法之後觸發。
奇怪的是，如果我同時調用兩個連接而不是另一個連接，他們都會觸發並調用委託方法。
下面是一些類有一些爲了清楚起見移除膽量的代碼：
應用程序委託：
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
// Set up analytics account
// Set the tab bar controller as the window's root view controller and display.
self.window.rootViewController = self.tabBarController;
[self.window makeKeyAndVisible];
//Set up listeners for event handling
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(timeStampResponse:) name:@"TimeStampResponse" object:nil];
//Set app loading screen
//Create new OperationQueue, set ActivityIndicator and run TimeStamp Check
parseQueue = [NSOperationQueue new];
[UIApplication sharedApplication].networkActivityIndicatorVisible = YES;
[self timeStampCheck];
return YES;
}
-(void)timeStampCheck {
NSLog(@"Time Stamp Check, Creating Connection");
NSURLRequest *timeStampURLRequest = [NSURLRequest requestWithURL:[NSURL URLWithString:kTimeStampURL]];
self.timeStampConnection = [[NSURLConnectionWithTag alloc] initWithRequest:timeStampURLRequest delegate:self startImmediately:YES tag:1];
}
-(void)newEventsNeeded {
NSLog(@"Event File Doesn't Exists or New File Needed, Creating Connection");
NSURLRequest *feedURLRequest = [NSURLRequest requestWithURL:[NSURL URLWithString:kEventFeedURL]];
self.eventsFeedConnection = [[NSURLConnectionWithTag alloc] initWithRequest:feedURLRequest delegate:self startImmediately:YES tag:0];
}
//Callback from DateStampParser
-(void)timeStampResponse:(NSNotification *)notif {
NSString *response = [[notif userInfo] objectForKey:@"TimeStampResponse"];
if ([response isEqualToString:@"NewEvents"]) {
[self newEventsNeeded];
self.appLoadingViewController.loadingLabel.text = @"New Events Found...";
} else if ([response isEqualToString:@"NoNewEvents"]){
[self allEventsLoaded];
}
}
而NSURLConnection的委託方法
-(void)connection:(NSURLConnectionWithTag *)connection didFailWithError:(NSError *)error {
if (connection.tag == 0) {
NSLog(@"Connection failed on Event Feed");
} else if (connection.tag == 1) {
NSLog(@"Connection failed on Time Stamp Check");
}
}
-(void)connection:(NSURLConnectionWithTag *)connection didReceiveResponse:(NSURLResponse *)response{
NSHTTPURLResponse *httpResponse = (NSHTTPURLResponse *)response;
NSLog(@"connection:didRecieveResponse:NSHTTPURLResponse");
if ((([httpResponse statusCode]/100) == 2)) {
//Handling for eventsFeedConnection
if (connection.tag == 0) {
NSLog(@"Connection tag = 0");
self.eventsData = [NSMutableData data];
} else if (connection.tag == 1) {
NSLog(@"Connection tag = 1");
//NSLog(@"Timestamp connection received response");
self.timeStampData = [NSMutableData data];
}
} else {
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Network Error" message:@"No Response from the Server" delegate:nil cancelButtonTitle:@"Ok" otherButtonTitles:nil];
[alert show];
[alert release];
}
}
-(void)connection:(NSURLConnectionWithTag *)connection didReceiveData:(NSData *)data{
//Handling for eventsFeedConnection
if (connection.tag == 0) {
self.appLoadingViewController.loadingLabel.text = @"Downloading Events...";
[eventsData appendData:data];
} else if (connection.tag == 1) {
self.appLoadingViewController.loadingLabel.text [email protected]"Checking for New Events...";
[timeStampData appendData:data];
}
}
-(void)connectionDidFinishLoading:(NSURLConnectionWithTag *)connection{
//Handling for eventsFeedConnection
if (connection.tag == 0) {
NSLog(@"EventFeed Connection Finished");
self.eventsFeedConnection = nil;
[eventsFeedConnection release];
ParserOperation *parser = [[ParserOperation alloc] initWithData:self.eventsData];
[parseQueue addOperation:parser];
[parser release];
self.eventsData = nil;
//[eventCategoryListViewController reenableRefreshButton];
} else if (connection.tag ==1){
NSLog(@"TimeStamp Connection Finished");
self.timeStampConnection = nil;
[timeStampConnection release];
DateStampParser *parser = [[DateStampParser alloc] initWithData:self.timeStampData];
[parseQueue addOperation:parser];
[parser release];
self.timeStampData = nil;
}
}
不知道這個代碼是否顯而易見，或者不是w問題是，但如果需要任何額外的代碼/澄清我想要完成什麼，請讓我知道。
感謝
編輯爲清楚起見 只是爲了澄清，在從NSLog的火災newEventsNeeded，只是委託方法不被解僱。
我無法看到您觸發通知的位置。它是否在你的問題中沒有顯示的代碼中？ – Codo
notif位於DateStampParser操作的末尾。它會觸發由timeStampResponse收到的notif。 – Chris
我知道這是一個真正的舊帖子，但我只想提到我最終修復它的方式，只是通過使用ASI HTTP庫來規避真正的問題。 – Chris