👀 Views: 250 💬 Answers: 1 📅 Created: 2025-06-15

android room livedata viewmodel kotlin

I am using Room for local data persistence in my Android app, and I have a situation where data retrieval via LiveData does not update the UI after I perform an insert operation. I have implemented a simple data insertion method, but even after the insert completes, the UI does not reflect the new data. Here’s a simplified version of what I have: ```kotlin @Entity(tableName = "users") data class User( @PrimaryKey(autoGenerate = true) val id: Int, val name: String ) @Dao interface UserDao { @Insert(onConflict = OnConflictStrategy.REPLACE) suspend fun insert(user: User) @Query("SELECT * FROM users") fun getAllUsers(): LiveData<List<User>> } @Database(entities = [User::class], version = 1) abstract class AppDatabase : RoomDatabase() { abstract fun userDao(): UserDao } class UserRepository(private val userDao: UserDao) { val allUsers: LiveData<List<User>> = userDao.getAllUsers() suspend fun insert(user: User) { userDao.insert(user) } } class UserViewModel(application: Application) : AndroidViewModel(application) { private val repository: UserRepository val allUsers: LiveData<List<User>> init { val userDao = AppDatabase.getDatabase(application).userDao() repository = UserRepository(userDao) allUsers = repository.allUsers } fun insert(user: User) = viewModelScope.launch { repository.insert(user) } } ``` I call `insert()` method from my UI when a user submits their name: ```kotlin val user = User(0, "John Doe") viewModel.insert(user) ``` However, the `LiveData` observer in the Activity doesn’t get triggered, and the UI remains unchanged. I have also ensured that the observer is set up correctly like this: ```kotlin viewModel.allUsers.observe(this, Observer { users -> // Update the UI userAdapter.submitList(users) }) ``` I have tried to troubleshoot this by ensuring that the Room database is initialized properly and that the insert operation is indeed completing successfully. I even added a log statement inside the observer, but it never gets called after the insert. Any insights on why my UI isn't updating after the database insert? Am I missing something in how the LiveData is being observed or any specific Room configurations? I'm using Room version 2.4.3 and Kotlin 1.7.0 with an Android target SDK of 33. Any ideas what could be causing this?