当应用程序处于睡眠状态时检测电话

Question

我正在尝试做的是一个在来电时运行代码的应用程序。我知道我无法获得来电者的任何详细信息，这很好。

到目前为止，我的问题是它仅在应用程序处于前台时才有效。

这是我的代码：

#import <CoreTelephony/CoreTelephonyDefines.h>
#import <CoreTelephony/CTCallCenter.h>
#import <CoreTelephony/CTCall.h>

CTCallCenter *callCenter = [[CTCallCenter alloc] init];

[callCenter setCallEventHandler:^(CTCall *call) {
    ONLog(@"Event handler called");
    if ([call.callState isEqualToString: CTCallStateConnected]) {
        ONLog(@"Connected");
    } else if ([call.callState isEqualToString: CTCallStateDialing]) {
        ONLog(@"Dialing");
    } else if ([call.callState isEqualToString: CTCallStateDisconnected]) {
        ONLog(@"Disconnected");
    } else if ([call.callState isEqualToString: CTCallStateIncoming]) {
        ONLog(@"Incomming");
    }
}];

有人可以帮我把它作为后台任务运行吗？

编辑：

我这样使用 Richas 的代码：

    __block UIBackgroundTaskIdentifier yourBackgroundTaskName;
    yourBackgroundTaskName = [application beginBackgroundTaskWithExpirationHandler:^{

        // CODE FOR EXPIRATION HANDLER BLOCK
        [application endBackgroundTask: yourBackgroundTaskName];
        yourBackgroundTaskName = UIBackgroundTaskInvalid;

    }];

    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{

        // DO YOUR STUFF HERE. START OF BACKGROUND TASK.
        NSLog(@"Background time Remaining: %f",[[UIApplication sharedApplication] backgroundTimeRemaining]);

        self.callCenter = [[CTCallCenter alloc] init];

        [self.callCenter setCallEventHandler:^(CTCall *call) {
            ONLog(@"Event handler called");
            if ([call.callState isEqualToString: CTCallStateConnected]) {
                ONLog(@"Connected");
            } else if ([call.callState isEqualToString: CTCallStateDialing]) {
                ONLog(@"Dialing");
            } else if ([call.callState isEqualToString: CTCallStateDisconnected]) {
                ONLog(@"Disconnected");
            } else if ([call.callState isEqualToString: CTCallStateIncoming]) {
                ONLog(@"Incomming");
            }
        }];


        //WHEN YOU ARE DONE WITH YOUR TASK, TELL THAT TO SYSTEM
        [application endBackgroundTask: yourBackgroundTaskName];
        yourBackgroundTaskName = UIBackgroundTaskInvalid;
    });

1. 它只为我买了 180 秒的后台运行...
2. 它不工作 :) 未检测到呼叫

Answer 1

您应该检查以下两种方法来解决您的问题：

- (UIBackgroundTaskIdentifier)beginBackgroundTaskWithName:(NSString *)taskName expirationHandler:(void (^)(void))handler`

- (UIBackgroundTaskIdentifier)beginBackgroundTaskWithExpirationHandler:(void (^)(void))handler

您可以在applicationDidEnterBackground 中实施其中的任何一个，这可以为您争取一些时间（5-10 分钟）。代码可能如下所示：

- (void)applicationDidEnterBackground:(UIApplication *)application
{
    UIBackgroundTaskIdentifier yourBackgroundTaskName;
    yourBackgroundTaskName = [application beginBackgroundTaskWithExpirationHandler:^{

          // CODE FOR EXPIRATION HANDLER BLOCK
          [application endBackgroundTask: yourBackgroundTaskName];
          yourBackgroundTaskName = UIBackgroundTaskInvalid;

    }];

    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{

         // DO YOUR STUFF HERE. START OF BACKGROUND TASK.

         //WHEN YOU ARE DONE WITH YOUR TASK, TELL THAT TO SYSTEM
         [application endBackgroundTask: yourBackgroundTaskName];
         yourBackgroundTaskName = UIBackgroundTaskInvalid;
    });
}

希望，这至少可以帮助您入门。