ios - 这是什么意思 : +[UAirship executeUnsafeTakeOff:]?

Question

我正在尝试使用 Urban Airship 设置推送通知，但我认为我在配置文件或 SSL 证书方面遇到了问题。该应用程序没有提示用户获得推送通知权限，但我没有收到“找不到应用程序的有效“aps-environment”授权字符串”消息，我可以在中看到 aps-environment 授权.mobileprovision。

我找不到关于 +[UAirship executeUnsafeTakeOff:] 的任何文档，所以我想知道是否有人知道这意味着什么？

此外，设备 token 返回为 nil，如 Urban Airship 所记录:

[D] -[UAPush updateRegistrationForcefully:] [Line 544] Device token is nil. Registration will be attempted at a later time

在 [UAirship takeOff:config] 调用之前没有运行 Urban Airship 代码，应用程序不会因错误而崩溃。

Answer 1

在不太了解 Urban Airship 的情况下，我可以提供一个猜测。

takeOff 确保 executeUnsafeTakeoff 中提供的实际实现仅发生一次。它确保当前线程是主线程，然后确保它只发生一次。

因此，收到 executeUnsafeTakeoff 错误实际上只会告诉您出现了问题，例如配置无法验证`(见下文)。

正如您提到的，您需要确保应用程序可以接收推送通知。

这是起飞:

+ (void)takeOff {
    [UAirship takeOff:[UAConfig defaultConfig]];
}

+ (void)takeOff:(UAConfig *)config {

    // takeOff needs to be run on the main thread
    if (![[NSThread currentThread] isMainThread]) {
        NSException *mainThreadException = [NSException exceptionWithName:UAirshipTakeOffBackgroundThreadException
                                                                   reason:@"UAirship takeOff must be called on the main thread."
                                                                 userInfo:nil];
        [mainThreadException raise];
    }

    dispatch_once(&takeOffPred_, ^{
        [UAirship executeUnsafeTakeOff:config];
    });
}

这里是executeUnsafeTakeoff:

/*
 * This is an unsafe version of takeOff - use takeOff: instead for dispatch_once
 */
+ (void)executeUnsafeTakeOff:(UAConfig *)config {
    // Airships only take off once!
    if (_sharedAirship) {
        return;
    }

    [UAirship setLogLevel:config.logLevel];

    _sharedAirship = [[UAirship alloc] init];
    _sharedAirship.config = config;

    // Ensure that app credentials have been passed in
    if (![config validate]) {

        UA_LERR(@"The AirshipConfig.plist file is missing and no application credentials were specified at runtime.");

        // Bail now. Don't continue the takeOff sequence.
        return;
    }

    UA_LINFO(@"App Key: %@", _sharedAirship.config.appKey);
    UA_LINFO(@"App Secret: %@", _sharedAirship.config.appSecret);
    UA_LINFO(@"Server: %@", _sharedAirship.config.deviceAPIURL);

    if (config.automaticSetupEnabled) {

        _sharedAirship.appDelegate = [[UAAppDelegateProxy alloc ]init];

        //swap pointers with the initial app delegate
        @synchronized ([UIApplication sharedApplication]) {
            _sharedAirship.appDelegate.originalAppDelegate = [UIApplication sharedApplication].delegate;
            _sharedAirship.appDelegate.airshipAppDelegate = [[UAAppDelegate alloc] init];
            [UIApplication sharedApplication].delegate = _sharedAirship.appDelegate;
        }
    }


    // Build a custom user agent with the app key and name
    [_sharedAirship configureUserAgent];

    // Set up analytics
    _sharedAirship.analytics = [[UAAnalytics alloc] initWithConfig:_sharedAirship.config];
    [_sharedAirship.analytics delayNextSend:UAAnalyticsFirstBatchUploadInterval];

    /*
     * Handle Debug Options
     */

    //For testing, set this value in AirshipConfig to clear out
    //the keychain credentials, as they will otherwise be persisted
    //even when the application is uninstalled.
    if (config.clearKeychain) {

        UA_LDEBUG(@"Deleting the keychain credentials");
        [UAKeychainUtils deleteKeychainValue:_sharedAirship.config.appKey];

        UA_LDEBUG(@"Deleting the UA device ID");
        [UAKeychainUtils deleteKeychainValue:kUAKeychainDeviceIDKey];
    }

    if (!config.inProduction) {
        [_sharedAirship validate];
    }

    if (config.cacheDiskSizeInMB > 0) {
        UA_LINFO("Registering UAURLProtocol");
        [NSURLProtocol registerClass:[UAURLProtocol class]];
    }

    // The singleton is now ready for use!
    _sharedAirship.ready = true;


    //create/setup user (begin listening for device token changes)
    [[UAUser defaultUser] initializeUser];

}