loadable error screen, reload actions, autoreload

lib/state/app/infrastructure/loadableState/bloc/loadable_state_bloc.dart

@@ -2,21 +2,47 @@ import 'dart:async';
 
 import 'package:bloc/bloc.dart';
 import 'package:connectivity_plus/connectivity_plus.dart';
+import 'package:flutter/material.dart';
 
+import '../loading_error.dart';
+import 'loadable_state_event.dart';
 import 'loadable_state_state.dart';
 
-class LoadableStateBloc extends Bloc<void, LoadableStateState> {
+class LoadableStateBloc extends Bloc<LoadableStateEvent, LoadableStateState> {
   late StreamSubscription<List<ConnectivityResult>> _updateStream;
+  LoadingError? loadingError;
 
   LoadableStateBloc() : super(const LoadableStateState(connections: null)) {
-    emitState(List<ConnectivityResult> v) => emit(state.copyWith(connections: v));
+    on<ConnectivityChanged>((event, emit) {
+      emit(event.state);
+      if(connectivityStatusKnown() && isConnected() && loadingError != null) {
+        if(!loadingError!.enableRetry) return;
+        loadingError!.retry!();
+      }
+    });
 
-    Connectivity().checkConnectivity().then(emitState);
-    _updateStream = Connectivity().onConnectivityChanged.listen(emitState);
+    emitConnectivity(List<ConnectivityResult> result) => add(ConnectivityChanged(LoadableStateState(connections: result)));
+
+    Connectivity().checkConnectivity().then(emitConnectivity);
+    _updateStream = Connectivity().onConnectivityChanged.listen(emitConnectivity);
   }
 
   bool connectivityStatusKnown() => state.connections != null;
-  bool isConnected({bool? def}) => !(state.connections?.contains(ConnectivityResult.none) ?? def!);
+  bool isConnected() => !(state.connections?.contains(ConnectivityResult.none) ?? true);
+  bool allowRetry() => loadingError?.retry != null;
+  bool showErrorMessage() => isConnected() && loadingError != null;
+
+  IconData connectionIcon() => connectivityStatusKnown()
+      ? isConnected()
+        ? Icons.nearby_error
+        : Icons.signal_wifi_connected_no_internet_4
+      : Icons.device_unknown;
+
+  String connectionText() => connectivityStatusKnown()
+      ? isConnected()
+        ? 'Verbindung fehlgeschlagen'
+        : 'Offline'
+      : 'Unbekannte Fehlerursache';
 
   @override
   Future<void> close() {

lib/state/app/infrastructure/loadableState/bloc/loadable_state_event.dart

@@ -0,0 +1,7 @@
+import 'loadable_state_state.dart';
+
+sealed class LoadableStateEvent {}
+final class ConnectivityChanged extends LoadableStateEvent {
+  final LoadableStateState state;
+  ConnectivityChanged(this.state);
+}