Show progress dialog when requesting info from server

lib/widget/dialogs.dart

@@ -0,0 +1,21 @@
+
+import 'package:flutter/cupertino.dart';
+import 'package:flutter/material.dart';
+
+void showProgressDialog(BuildContext context, String title, String description) {
+  showDialog(
+    context: context,
+    barrierDismissible: false,
+    child: SimpleDialog(
+      title: Text(title),
+      children: <Widget>[
+        CircularProgressIndicator(),
+        Text(description),
+      ],
+    )
+  );
+}
+
+void hideProgressDialog(BuildContext context) {
+  Navigator.pop(context);
+}