- Introduction on base view model and stateless widget classes

- Implementation of firebase
- Implementation of dependency injection

Took 11 hours 26 minutes

lib/widgets/LoaderWidget.dart

@@ -0,0 +1,61 @@
+
+import 'package:flutter/cupertino.dart';
+import 'package:flutter/material.dart';
+
+class LoaderWidget extends StatefulWidget {
+
+  final Widget body;
+  LoaderWidget({this.body, Key key}): super(key: key);
+
+  @override
+  LoaderWidgetState createState() => LoaderWidgetState();
+}
+
+class LoaderWidgetState extends State<LoaderWidget> {
+  bool _status = false;
+
+  @override
+  void initState() {
+    super.initState();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Center(
+      child: _status ? Center(child: CircularProgressIndicator())
+          : Center(
+        child: widget.body,
+      ),
+    );
+  }
+
+  void changeState(){
+    setState(() {
+      _status = !_status;
+    });
+  }
+}
+
+abstract class LoaderStatelessWidget extends StatelessWidget{
+  final loaderKey = GlobalKey<LoaderWidgetState>();
+
+  void changeState(){
+    loaderKey.currentState.changeState();
+  }
+
+  Widget LoaderWidgeted({Widget body}){
+    return LoaderWidget(body: body, key: loaderKey);
+  }
+}
+
+abstract class LoaderStatefulWidget<T extends StatefulWidget> extends State<T>{
+  final loaderKey = GlobalKey<LoaderWidgetState>();
+
+  void changeState(){
+    loaderKey.currentState.changeState();
+  }
+
+  Widget LoaderWidgeted(Widget body, Key key){
+    return LoaderWidget(body: body, key: key);
+  }
+}