android: show "export prohibited" alert on enabling app data backup with random db password set (#1962)

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

@@ -190,7 +190,7 @@ fun DatabaseLayout(
         disabled = operationsDisabled
       )
       SectionDivider()
-      SettingsPreferenceItem(Icons.Outlined.Backup, stringResource(R.string.full_backup), privacyFullBackup)
+      AppDataBackupPreference(privacyFullBackup, initialRandomDBPassphrase)
       SectionDivider()
       SettingsActionItem(
         Icons.Outlined.IosShare,
@@ -270,6 +270,36 @@ fun DatabaseLayout(
   }
 }
 
+@Composable
+private fun AppDataBackupPreference(privacyFullBackup: SharedPreference<Boolean>, initialRandomDBPassphrase: SharedPreference<Boolean>) {
+  SectionItemView {
+    Row(verticalAlignment = Alignment.CenterVertically) {
+      Icon(Icons.Outlined.Backup, stringResource(R.string.full_backup), tint = HighOrLowlight)
+      Spacer(Modifier.padding(horizontal = 4.dp))
+      val prefState = remember { mutableStateOf(privacyFullBackup.get()) }
+      Row(Modifier.fillMaxWidth(), verticalAlignment = Alignment.CenterVertically) {
+        Text(stringResource(R.string.full_backup), Modifier.padding(end = 24.dp))
+        Spacer(Modifier.fillMaxWidth().weight(1f))
+        Switch(
+          checked = prefState.value,
+          onCheckedChange = {
+            if (initialRandomDBPassphrase.get()) {
+              exportProhibitedAlert()
+            } else {
+              privacyFullBackup.set(it)
+              prefState.value = it
+            }
+          },
+          colors = SwitchDefaults.colors(
+            checkedThumbColor = MaterialTheme.colors.primary,
+            uncheckedThumbColor = HighOrLowlight
+          )
+        )
+      }
+    }
+  }
+}
+
 private fun setChatItemTTLAlert(
   m: ChatModel, selectedChatItemTTL: MutableState<ChatItemTTL>,
   progressIndicator: MutableState<Boolean>,

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

@@ -13,7 +13,6 @@ import androidx.compose.runtime.*
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.platform.LocalContext
-import androidx.compose.ui.platform.LocalView
 import androidx.compose.ui.res.stringResource
 import androidx.fragment.app.FragmentActivity
 import chat.simplex.app.R