android: splash screen (to avoid showing welcome screen before the user is loaded) (#345)

* initial attempt -- not recomposing

* change to mutable state, still not working

* two state works, why not three?

* fix so we actually change state

* remove unnecessary brackets

* refactor

* using Boolean? for userCreated

Co-authored-by: Evgeny Poberezkin <2769109+epoberezkin@users.noreply.github.com>

apps/android/app/src/main/java/chat/simplex/app/MainActivity.kt

@@ -53,10 +53,10 @@ class SimplexViewModel(application: Application): AndroidViewModel(application)
 @ExperimentalMaterialApi
 @Composable
 fun MainPage(chatModel: ChatModel, nav: NavController) {
-  if (chatModel.currentUser.value == null) WelcomeView(chatModel) {
-    nav.navigate(Pages.ChatList.route)
-  } else {
-    ChatListView(chatModel, nav)
+  when (chatModel.userCreated.value) {
+    null -> SplashView()
+    false -> WelcomeView(chatModel) { nav.navigate(Pages.ChatList.route) }
+    true -> ChatListView(chatModel, nav)
   }
 }
 

apps/android/app/src/main/java/chat/simplex/app/model/ChatModel.kt

@@ -10,6 +10,7 @@ import kotlinx.serialization.Serializable
 
 class ChatModel(val controller: ChatController, val alertManager: SimplexApp.AlertManager) {
   var currentUser = mutableStateOf<User?>(null)
+  var userCreated = mutableStateOf<Boolean?>(null)
   var chats = mutableStateListOf<Chat>()
   var chatId = mutableStateOf<String?>(null)
   var chatItems = mutableStateListOf<ChatItem>()

apps/android/app/src/main/java/chat/simplex/app/model/SimpleXAPI.kt

@@ -18,6 +18,7 @@ open class ChatController(val ctrl: ChatCtrl, val alertManager: SimplexApp.Alert
 
   suspend fun startChat(u: User) {
     chatModel.currentUser = mutableStateOf(u)
+    chatModel.userCreated.value = true
     Log.d("SIMPLEX (user)", u.toString())
     try {
       apiStartChat()
@@ -63,6 +64,7 @@ open class ChatController(val ctrl: ChatCtrl, val alertManager: SimplexApp.Alert
     val r = sendCmd(CC.ShowActiveUser())
     if (r is CR.ActiveUser) return r.user
     Log.d("SIMPLEX", "apiGetActiveUser: ${r.responseType} ${r.details}")
+    chatModel.userCreated.value = false
     return null
   }
 

apps/android/app/src/main/java/chat/simplex/app/views/SplashView.kt

@@ -0,0 +1,23 @@
+package chat.simplex.app.views
+
+import androidx.compose.foundation.Image
+import androidx.compose.foundation.layout.*
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.res.painterResource
+import androidx.compose.ui.unit.dp
+import chat.simplex.app.R
+
+@Composable
+fun SplashView() {
+  Box(modifier = Modifier.fillMaxSize()) {
+    Image(
+      painter = painterResource(R.drawable.logo),
+      contentDescription = "Simplex Icon",
+      modifier = Modifier
+        .height(230.dp)
+        .align(Alignment.Center)
+    )
+  }
+}