当我尝试登录用户并通过解析启用推送通知时，我的应用程序崩溃 [英] My app crashes when I try to log sign up a user and enable push notifications through parse

问题描述

我正在尝试通过解析启用推送通知.如果已经有用户缓存并登录到应用程序，则解析通知代码将起作用.但是，如果我注销并尝试注册新用户，则该应用程序将崩溃，并且会显示错误消息:"NSInvalidArgumentException"，原因:对于PFObject上的键或值，不能使用nil.使用NSNull作为值.'...我相信问题出在应用程序委托内的didRegisterForRemoteNotificationsWithDeviceToken方法.由于没有currentUser登录，因此当应用尝试创建PFInstallation时，所有关联字段都返回nil.我已经在运行PFInstallation代码之前尝试过if语句来检查currentUser，但是该应用程序仍然崩溃.发生注册后，我需要注册通知，但是我无法弄清楚该怎么做，因为在应用程序委托中需要发生didRegisterForRemoteNotificationsWithDeviceToken.任何建议或解决方案表示赞赏.我的代码段如下.谢谢！

I'm trying to enable push notifications through parse. The parse notification code works if there is already a user cached and signed into the app. If I logout and try to signup a new user, however, the app crashes and I get an error that states: 'NSInvalidArgumentException', reason: 'Can't use nil for keys or values on PFObject. Use NSNull for values.'...I believe the issue is with the didRegisterForRemoteNotificationsWithDeviceToken method within the app delegate. Because there isn't a currentUser logged in, when the app tries creating a PFInstallation, all of the associating fields are returning nil. I have tried an if statement checking for a currentUser before running the PFInstallation code, but the app still crashes. I need to register for notifications after signup occurs, but I can't figure out how to do that seeing as didRegisterForRemoteNotificationsWithDeviceToken needs to occur in the app delegate. Any advice or solutions are appreciate. My code snippet is below. Thanks!

此代码现在可用！

- (void)application:(UIApplication *)application
didRegisterForRemoteNotificationsWithDeviceToken:(NSData *)newDeviceToken
{
    PFInstallation *currentInstallation = [PFInstallation currentInstallation];
    if ([PFUser currentUser] != nil) 
    {
        currentInstallation[@"currentUser"]=[PFUser currentUser];
    }
    else 
    {
        [currentInstallation removeObjectForKey:@"currentUser"];
    }
    [currentInstallation setDeviceTokenFromData:newDeviceToken];
    [currentInstallation saveInBackground];

}

用于发送推送通知

- (IBAction)send:(id)sender
{
    PFQuery *userQuery = [PFUser query];
    [userQuery whereKey:@"objectId" equalTo:self.recipient.objectId];
    PFQuery *query = [PFInstallation query];
    [query whereKey:@"user" matchesQuery:userQuery];

    NSString *sendingUser = self.currentUser.username;

    NSString *message = [NSString stringWithFormat:@"from %@: \n %@", sendingUser,self.message.text];

    PFPush *push= [[PFPush alloc]init];
    [push setQuery:query];
    [push setMessage:message];
    [push sendPushInBackground];

    NSLog(@"Message sent!");

    [self dismissViewControllerAnimated:NO completion:nil];

}

推荐答案

您仍然可以在没有当前用户的情况下注册安装，但是必须确保将该用户从注册中删除-

You can still register an installation without a current user, but you have to make sure that the user is removed from the registration -

- (void)application:(UIApplication *)application
didRegisterForRemoteNotificationsWithDeviceToken:(NSData *)deviceToken
{
    // Store the deviceToken in the current installation and save it to Parse.
    PFInstallation *currentInstallation = [PFInstallation currentInstallation];
    if ([PFUser currentUser] != nil)
    {
        currentInstallation[@"currentUser"]=[PFUser currentUser];
    }
    else {
        [currentInstallation removeObjectForKey:@"currentUser"];
    }
    [currentInstallation setDeviceTokenFromData:deviceToken];
    [currentInstallation saveInBackground];
}

然后，无论您在哪里处理登录/注销事件，都可以更新当前安装记录.例如-

Then, wherever you handle login/logout events you can update the current installation record. For example -

-(void) loggedIn
{  

    PFInstallation *currentInstallation=[PFInstallation currentInstallation];
    currentInstallation[@"currentUser"]=[PFUser currentUser];
    [currentInstallation saveInBackground];

}

-(void) notLoggedIn
{

    PFInstallation *currentInstallation=[PFInstallation currentInstallation];
    [currentInstallation removeObjectForKey:@"currentUser"];
    [currentInstallation saveInBackground];

}

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