小编Jam*_*e22的帖子

我正在使用Firebase,根据他们的文档,我正在检查用户的登录状态是否发生了变化.问题在于侦听器块,其中代码在应用程序启动时被调用两次(用户已登录).这不是太多的交易,但Firebase在连接中创建两个值并删除它们.我该如何解决这个问题？我需要在监听器中获取用户之后调用它,而不是在外部,因为如果没有先完成获取用户数据,则无法保证用户将在该块之外存在.

FIRAuth.auth()?.addAuthStateDidChangeListener { auth, user in
        if let theUser = user {
            // User is signed in.

            // CODE IN HERE IS CALLED TWICE UPON APP LAUNCH (WHEN USERS LOGGED IN).... WHY?
            self.currentUser = theUser
            print("LOGGED IN!!!!")


            self.updateUsersStatus(user: self.currentUser)

        } else {
            // No user is signed in.
            self.performSegueWithIdentifier(SEGUE_LOG_IN, sender: self)
        }
    }

尝试使用以下代码使用Facebook + Parse登录:

我注意到单击Login with Facebook按钮时,它会在控制台中显示两次.

-canOpenURL:URL失败:"fbauth2://" - 错误:"此应用程序不允许查询方案fbauth2"

这是我的代码:

- (IBAction)loginWithFacebook:(id)sender {
        // Set permissions required from the facebook user account
        NSArray *permissionsArray = @[ @"user_about_me", @"user_relationships", @"user_birthday", @"user_location"];

        // Login PFUser using Facebook
        [PFFacebookUtils logInWithPermissions: permissionsArray block:^(PFUser * _Nullable user, NSError * _Nullable error) {
            if (!user) {
                NSLog(@"Uh oh. The user cancelled the Facebook login.");
            } else if (user.isNew) {
                NSLog(@"User signed up and logged in through Facebook!");
            } else {
                NSLog(@"User logged in through Facebook!");
            } …

我正在尝试将MKMapView上的用户默认位置注释从蓝色更改为名为geo的自定义图像。设置断点时会碰到将其设置为geo的那条线，但是两个点（用户默认点和“乘客点”都是默认的红色精确点注释）是我设置的错误，还是存在某些图像规定？

func mapView(mapView: MKMapView, viewForAnnotation annotation: MKAnnotation) -> MKAnnotationView? {

        if annotation.isKindOfClass(PassengerLocation) == false {

            //User location
            let userIdentifier = "UserLocation"
            var annotationView = mapView.dequeueReusableAnnotationViewWithIdentifier(userIdentifier)

            if annotationView == nil {
                annotationView = MKPinAnnotationView(annotation:annotation, reuseIdentifier:userIdentifier)
            }
            annotationView!.annotation = annotation
            annotationView!.canShowCallout = true

            // THIS IS NOT WORKING, DEFAULT RED PIN POINT STILL SHOWING
            annotationView!.image = UIImage(named: "geo")
            return annotationView


        }

        let identifier = "PassengerLocation"

        if let annotationView = mapView.dequeueReusableAnnotationViewWithIdentifier(identifier) {
            annotationView.annotation = annotation

            return annotationView
        } else {
            let annotationView = …

我正在使用Firebase的新框架,我试图分别在Login和Signup VC上监控用户的登录状态.问题是如果登录状态在SignUp视图上发生更改,则也会调用Login视图上的Auth State.我的问题是,如何删除身份验证状态？我在Firebase网站上找到了语法,但考虑到我的auth状态代码,我对于传递什么感到困惑:

FIRAuth.auth()?.addAuthStateDidChangeListener { auth, user in
            if let theUser = user {
                // User is signed in.
                print("LOGGED IN!!!!  :::: \(theUser)")
                self.dismissViewControllerAnimated(true, completion: nil)
            } else {
                // No user is signed in.
                print("Need to login first.")
            }
        }

用于删除身份验证的代码,但不确定要传递的内容.

FIRAuth.auth()?.removeAuthStateDidChangeListener(FIRAuthStateDidChangeListenerHandle) 

说我传入了一个FIRAuthStateDidChangeListenerHandle,但是我如何获得这个,或者我是否以不同的方式重写我的authState代码？

我希望将每个特定对象的dataSnapshot和key的引用传递给自定义的"Message"对象.

我已经尝试在Message.class中使用键'String key',但它似乎返回null.

这是我的Message对象当前的方式:

public class Message {

    private String key;
    private String sender_id;
    private String sender_username;
    private String receiver_username;
    private String receiver_id;
    private String chat_id;
    private String message;
    private Firebase ref;
    private double createdAt;
    private boolean read;

    public Message() {
        // empty default constructor, necessary for Firebase to be able to deserialize messages
    }

    public String getKey() { return key; }
    public String getSender_id() { return sender_id; }
    public String getSender_username() { return sender_username; }
    public String getReceiver_username() { …