implemented new loadable state concept

lib/state/app/infrastructure/loadableState/view/loadable_state_background_loading.dart

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+import 'package:flutter/material.dart';
+
+class LoadableStateBackgroundLoading extends StatelessWidget {
+  final bool visible;
+  const LoadableStateBackgroundLoading({required this.visible, super.key});
+
+  final Duration animationDuration = const Duration(milliseconds: 200);
+
+  @override
+  Widget build(BuildContext context) => AnimatedSwitcher(
+      duration: animationDuration,
+      transitionBuilder: (Widget child, Animation<double> animation) => SlideTransition(
+        position: Tween<Offset>(
+          begin: const Offset(0.0, -1.0),
+          end: Offset.zero,
+        ).animate(animation),
+        child: child,
+      ),
+      child: visible ? const LinearProgressIndicator() : const SizedBox.shrink(),
+    );
+}

lib/state/app/infrastructure/loadableState/view/loadable_state_consumer.dart

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+import 'package:bloc/bloc.dart';
+import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
+
+import '../loadable_state.dart';
+import 'loadable_state_background_loading.dart';
+import 'loadable_state_error_bar.dart';
+import 'loadable_state_primary_loading.dart';
+
+// TODO might be a simpler way
+class LoadableStateConsumer<TController extends Bloc<dynamic, TWrappedState>, TWrappedState extends LoadableState<TState>, TState> extends StatelessWidget {
+  final Widget Function(TState state) child;
+  const LoadableStateConsumer({required this.child, super.key});
+
+  static Duration animationDuration = const Duration(milliseconds: 200);
+
+  @override
+  Widget build(BuildContext context) {
+    var state = context.read<TController>().state as LoadableState<TState>;
+
+    return Column(
+      children: [
+        LoadableStateErrorBar(visible: state.showError()),
+        Expanded(
+          child: Stack(
+            children: [
+              LoadableStatePrimaryLoading(visible: state.showPrimaryLoading()),
+              LoadableStateBackgroundLoading(visible: state.showBackgroundLoading()),
+
+              AnimatedOpacity(
+                  opacity: state.showContent() ? 1.0 : 0.0,
+                  duration: animationDuration,
+                  curve: Curves.easeInOut,
+                  child: state.showContent() ? child(state.data) : const SizedBox.shrink()
+              ),
+            ],
+          ),
+        )
+      ],
+    );
+  }
+}

lib/state/app/infrastructure/loadableState/view/loadable_state_error_bar.dart

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+import 'package:flutter/material.dart';
+import 'package:flutter_bloc/flutter_bloc.dart';
+
+import '../../utilityWidgets/bloc_providing_builder.dart';
+import '../bloc/loadable_state_bloc.dart';
+import '../bloc/loadable_state_state.dart';
+
+class LoadableStateErrorBar extends StatelessWidget {
+  final bool visible;
+  const LoadableStateErrorBar({required this.visible, super.key});
+
+  final Duration animationDuration = const Duration(milliseconds: 200);
+
+  @override
+  Widget build(BuildContext context) => BlocProvidingBuilder<LoadableStateBloc, LoadableStateState>(
+    create: (context) => LoadableStateBloc(),
+    child: (context, state) => AnimatedSize(
+      duration: animationDuration,
+      child: AnimatedSwitcher(
+          duration: animationDuration,
+          transitionBuilder: (Widget child, Animation<double> animation) => SlideTransition(
+            position: Tween<Offset>(
+              begin: const Offset(0.0, -1.0),
+              end: Offset.zero,
+            ).animate(animation),
+            child: child,
+          ),
+          child: Visibility(
+              key: Key(visible.hashCode.toString()),
+              visible: visible,
+              replacement: const SizedBox(width: double.infinity),
+              child: Builder(
+                builder: (context) {
+                  var controller = context.watch<LoadableStateBloc>();
+                  var status = controller.connectivityStatusKnown() && !controller.isConnected()
+                      ? (icon: Icons.wifi_off_outlined, text: 'Offline', color: Colors.grey.shade600)
+                      : (icon: Icons.wifi_find_outlined, text: 'Verbindung fehlgeschlagen', color: Theme.of(context).primaryColor);
+
+                  return Container(
+                    height: 20,
+                    decoration: BoxDecoration(
+                      color: status.color,
+                    ),
+                    child: Row(
+                      mainAxisAlignment: MainAxisAlignment.center,
+                      children: [
+                        Icon(status.icon, size: 14),
+                        const SizedBox(width: 10),
+                        Text(status.text, style: const TextStyle(fontSize: 12))
+                      ],
+                    ),
+                  );
+                },
+              )
+          )
+      ),
+    ),
+  );
+}

lib/state/app/infrastructure/loadableState/view/loadable_state_primary_loading.dart

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+import 'package:flutter/material.dart';
+
+class LoadableStatePrimaryLoading extends StatelessWidget {
+  final bool visible;
+  const LoadableStatePrimaryLoading({required this.visible, super.key});
+
+  final Duration animationDuration = const Duration(milliseconds: 200);
+
+  @override
+  Widget build(BuildContext context) => AnimatedOpacity(
+      opacity: visible ? 1.0 : 0.0,
+      duration: animationDuration,
+      curve: Curves.easeInOut,
+      child: const Center(child: CircularProgressIndicator()),
+    );
+}