[add] function implementation

app/src/main/java/com/acitelight/aether/viewModel/MeScreenViewModel.kt

@@ -0,0 +1,52 @@
+package com.acitelight.aether.viewModel
+
+import android.app.Application
+import android.widget.Toast
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.ui.platform.LocalContext
+import androidx.datastore.preferences.core.edit
+import androidx.datastore.preferences.core.stringPreferencesKey
+import androidx.lifecycle.AndroidViewModel
+import androidx.lifecycle.viewModelScope
+import com.acitelight.aether.dataStore
+import com.acitelight.aether.model.Video
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.first
+import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.launch
+
+class MeScreenViewModel(application: Application) : AndroidViewModel(application)
+{
+    private val dataStore = application.dataStore
+    private val USER_NAME_KEY = stringPreferencesKey("user_name")
+    private val PRIVATE_KEY   = stringPreferencesKey("private_key")
+
+    val userNameFlow: Flow<String> = dataStore.data.map { preferences ->
+        preferences[USER_NAME_KEY] ?: ""
+    }
+
+    val privateKeyFlow: Flow<String> = dataStore.data.map {  preferences ->
+        preferences[PRIVATE_KEY] ?: ""
+    }
+
+    val username = mutableStateOf("");
+    val privateKey = mutableStateOf("")
+
+    init {
+        viewModelScope.launch {
+            username.value = userNameFlow.first()
+            privateKey.value = privateKeyFlow.first()
+        }
+    }
+
+    fun updateAccount(u: String, p: String)
+    {
+        viewModelScope.launch {
+            dataStore.edit { preferences ->
+                preferences[USER_NAME_KEY] = u
+                preferences[PRIVATE_KEY] = p
+            }
+        }
+    }
+}