Question

我正在创建一个应用程序，在应用程序关闭后发送推送通知。我正在使用AFNetworking与我的服务器通信。这是我的AFNetworking功能。

-(void)sendPushNotification:(NSMutableDictionary *)params onCompletion:(JSONResponseBlock)completionBlock{
    NSLog(@"%@%@",kAPIHost,kAPIPush);
    NSMutableURLRequest *apiRequest = [self multipartFormRequestWithMethod:@"POST" path:kAPIPush parameters:params constructingBodyWithBlock:^(id <AFMultipartFormData>formData){
        //TODO: attach file if needed
    }];
    NSLog(@"Till here");
    AFJSONRequestOperation *operation = [[AFJSONRequestOperation alloc] initWithRequest:apiRequest];
    [operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject){
        //success !
        NSLog(@"SUCCESSSS!");
        completionBlock(responseObject);
    }failure:^(AFHTTPRequestOperation *operation, NSError *error){
        //Failure
        NSLog(@"FAILUREE!");
        completionBlock([NSDictionary dictionaryWithObject:[error localizedDescription] forKey:@"error"]);
    }];
    NSLog(@"tille here 2");
    [operation start];
    NSLog(@"till here 3");
}

然后，为了发送推送，我有以下代码。

- (IBAction)changeEnglish:(id)sender {
    [[NSUserDefaults standardUserDefaults] setObject:[NSArray arrayWithObjects:@"en", nil] forKey:@"AppleLanguages"];
    [[NSUserDefaults standardUserDefaults] synchronize];
    NSString *alertCancel = NSLocalizedString(@"Home_alertCancel", nil);
    NSString *message = @"  Do you wish to change the language? The application will shut down after this. Next up you can restart it again.";

    BlockAlertView *alert = [BlockAlertView alertWithTitle:@"Change language" message:message];

    [alert setCancelButtonWithTitle:alertCancel block:nil];
    [alert setDestructiveButtonWithTitle:@"Ok" block:^{
        [self sendPush];
        exit(0);
    }];
}
-(void)sendPush{
    [[API sharedInstance]sendPushNotification:NULL onCompletion:^(NSDictionary *json){
        //completion
        if(![json objectForKey:@"error"]){
            NSLog(@"notification send");
        }else {
            NSLog(@"Cannot connect to the server");
        }
    }];

}

首先，当我在浏览器中执行推送通知时（在我的浏览器中输入链接并按Enter键）它可以正常工作。但是当我想在代码中执行时。它给出了以下日志。

2012-12-12 13:44:43.695 doktersApp[666:907] http://linkexample/simplepush.php
2012-12-12 13:44:43.702 doktersApp[666:907] till here
2012-12-12 13:44:43.705 doktersApp[666:907] till here2
2012-12-12 13:44:43.706 doktersApp[666:907] till here3

Answer 1

你想在退出时这样做吗？那么问题是请求是异步的。操作系统不等待它并杀死应用程序并且操作没有完成但是在你打电话开始后就被杀死了。

一个解决方案是将它包装在backgroundTask中，并告诉ios退出后需要更多时间。

示例：

- (void)applicationDidEnterBackground:(UIApplication *)application
{
    //begin
    UIBackgroundTaskIdentifier identifier = [application beginBackgroundTaskWithExpirationHandler:^{
        NSLog(@"expired");
    }];
    assert(identifier != UIBackgroundTaskInvalid);

    //this simulates a request
    double delayInSeconds = 2.0;
    dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, (int64_t)(delayInSeconds * NSEC_PER_SEC));
    dispatch_after(popTime, dispatch_get_main_queue(), ^(void){
        //THIS is your completion handler
        NSLog(@"done");
        [application endBackgroundTask:identifier];
    });
}

在你的具体案例中:(这显然是未经测试的，以上是经过测试的）

- (void)applicationDidEnterBackground:(UIApplication *)application
{
    //begin
    UIBackgroundTaskIdentifier identifier = [application beginBackgroundTaskWithExpirationHandler:^{
        NSLog(@"expired");
    }];
    assert(identifier != UIBackgroundTaskInvalid);

    [[API sharedInstance]sendPushNotification:NULL onCompletion:^(NSDictionary *json){
        //completion
        if(![json objectForKey:@"error"]){
            NSLog(@"notification send");
        }else {
            NSLog(@"Cannot connect to the server");
        }
        NSLog(@"done");
        [application endBackgroundTask:identifier];
    }];
}

POST请求未通过服务器成功发送

1 个答案: