package com.example.userprofile
import android.os.Bundle
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.padding
import androidx.compose.material3.Button
import androidx.compose.material3.Text
import androidx.compose.material3.MaterialTheme
import androidx.compose.material3.Surface
import androidx.compose.runtime.Composable
import androidx.compose.runtime.collectAsState
import androidx.compose.runtime.getValue
import androidx.compose.ui.Modifier
import androidx.compose.ui.unit.dp
import dagger.hilt.android.AndroidEntryPoint
import dagger.hilt.android.lifecycle.HiltViewModel
import javax.inject.Inject
import androidx.lifecycle.ViewModel
import androidx.lifecycle.viewModelScope
import kotlinx.coroutines.flow.MutableStateFlow
import kotlinx.coroutines.flow.StateFlow
import kotlinx.coroutines.launch
// Data class representing a user
data class User(val name: String, val email: String)
// Repository interface
interface UserRepository {
suspend fun getUser(): User
}
// Fake implementation of UserRepository
class FakeUserRepository @Inject constructor() : UserRepository {
override suspend fun getUser(): User {
// Simulate network or database delay
kotlinx.coroutines.delay(500)
return User(name = "Alice Johnson", email = "alice@example.com")
}
}
// ViewModel with injected UserRepository
@HiltViewModel
class UserProfileViewModel @Inject constructor(
private val userRepository: UserRepository
) : ViewModel() {
private val _user = MutableStateFlow<User?>(null)
val user: StateFlow<User?> = _user
init {
loadUser()
}
fun loadUser() {
viewModelScope.launch {
val fetchedUser = userRepository.getUser()
_user.value = fetchedUser
}
}
}
@AndroidEntryPoint
class UserProfileActivity : ComponentActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContent {
MaterialTheme {
Surface(modifier = Modifier.padding(16.dp)) {
UserProfileScreen()
}
}
}
}
}
import androidx.hilt.navigation.compose.hiltViewModel
@Composable
fun UserProfileScreen(viewModel: UserProfileViewModel = hiltViewModel()) {
val userState by viewModel.user.collectAsState()
Column(modifier = Modifier.padding(16.dp)) {
if (userState == null) {
Text(text = "Name: Loading...")
Text(text = "Email: Loading...")
} else {
Text(text = "Name: ${userState.name}")
Text(text = "Email: ${userState.email}")
}
Button(onClick = { viewModel.loadUser() }, modifier = Modifier.padding(top = 16.dp)) {
Text("Refresh")
}
}
}This solution uses Hilt to inject the UserRepository into the UserProfileViewModel. The repository provides user data asynchronously. The ViewModel exposes this data as a StateFlow which the composable observes to update the UI reactively.
The UserProfileScreen composable uses hiltViewModel() to get the ViewModel instance with dependencies injected. It shows loading text while data is null, then displays the user's name and email once loaded. The Refresh button triggers reloading the user data.
This pattern cleanly separates data fetching logic from UI, making the code easier to test and maintain.
