Layout created for single screen app

lib/BaseViewModel.dart

@@ -0,0 +1,24 @@
+import 'package:stacked/stacked.dart';
+
+import 'Utils/ViewState.dart';
+
+abstract class BaseViewmodel extends BaseViewModel{
+
+  ViewState _viewState = Idle();
+  ViewState get viewState => _viewState;
+
+  void onStart() {
+    _viewState = HasStarted();
+    notifyListeners();
+  }
+
+  void onSuccess(dynamic data) {
+    _viewState = HasData(data);
+    notifyListeners();
+  }
+
+  void onError(String error) {
+    _viewState = HasError(error);
+    notifyListeners();
+  }
+}