firebase-realtime-database

问题 I am planning a mobile application to use Firebase as its database/authentication provider mainly because I have found the authentication really easy to implement and also because of the apps nature. The app itself revolves around users in groups. Within each group is a range of data that will be accessible by every user in that group. I am wanting some feedback on my proposed firebase database structure and if there is anything I should do differently or could do better. Current proposed

问题 Android studio showed a warning so with ALT + ENTER the code val name = data[USERNAME] as String became val name = data?.get(USERNAME) as String but my emulator is still crashing thoughtsCollectionRef.get() .addOnSuccessListener { snapshot -> for(document in snapshot.documents){ val data = document.data //this is my code after listening to android studio val name = data?.get(USERNAME) as String val timestamp = data?.get(TIMESTAMP) as Date val thoughtTxt = data?.get(THOUGHT_TXT) as String val

问题 Android studio showed a warning so with ALT + ENTER the code val name = data[USERNAME] as String became val name = data?.get(USERNAME) as String but my emulator is still crashing thoughtsCollectionRef.get() .addOnSuccessListener { snapshot -> for(document in snapshot.documents){ val data = document.data //this is my code after listening to android studio val name = data?.get(USERNAME) as String val timestamp = data?.get(TIMESTAMP) as Date val thoughtTxt = data?.get(THOUGHT_TXT) as String val

问题 I am facing (again) a null object error. My App compiles just fine but after the splashscreen the App crashes with showing the Logcat I posted down there. The Error occurs in my Home Activity. The Interesting thing is that I had cases when the App was running like it should be with also putting the Common.currentUser.Name correctly. That was directly after the registration of a new user, which means the Code is working. Now to my questions; How can I initialize the current User in my

问题 This question already exists : How can I count the number of user from collection join to another collection firebase real time not firstore and angular 8 [closed] Closed 2 days ago . In my application I am using the Firebase Realtime Database and each user can make one or more posts. These posts are stored under /posts and each post contains a userId object. How do I make a query to count the number of posts made by a particular user with this database structure? I am using Typescript &

问题 So yeah the title has the question. A little information this is what my Firebase database looks like: And this is the current code: export function updateQTY(barcode) { database.ref('items/' + barcode).update({ qty: currentQTY(barcode) }) } export function currentQTY(barcode) { database.ref('items/' + barcode).once('value').then(function(snapshot) { var qty = snapshot.val().qty console.log(qty) }) return qty + 1 } Basically, What I want is for the qty + 1 to be returned to the function

问题 I am trying to add data by respective userIDs in Firebase by sign up the user, but it gives me error " unexpectedly found nil while unwrapping an optional value " now I don't know what the matter is. But when I use code without adding userID in ref respectively the data is added successfully. but when I add userID following ref then got error. SignUp let userID = FIRAuth.auth()?.currentUser?.uid ref.child("user_registration").child(userID!).setValue(["username": self.fullName.text, "email":

问题 I am currently trying to create something like this on Firebase: "Assets": { "asset001" : { "name": "DESK001", "owner: "owner's name", "brand: "HP", }, "asset002" : { "name": "NOTE001", "owner: "owner's name", "brand: "Dell", }, ... } But, i dont know how to automatically increment the value on "asset001"... i have seen the push() method, but then i wouldn't know how to retrieve the data. Here's what i have so far: JavaScript //Get the inputs ID from HTML var inputName = document

问题 I have two observers, the second observer is dependent on the first observers value. I can't seem to get the first observer to work, I am not getting any errors on Xcode. The first function has to check the Users profile for information and then use that information to search for different information in the database. Here is my code: func loadposts() { ref = Database.database().reference() let trace = Performance.startTrace(name: "test trace") trace?.incrementCounter(named:"retry") let

问题 Currently I'm designing an application in Swift 3.0 that will be used by a small group up to 100 users. Users will register through a simple registration form using email id and password but Admin will have to approve or reject the user registration request manually. Workflow I can think of is if a user register, admin will get some notification or email that a new user registration request is there and then when admin approve or rejects the user registration request and user will get a email