Init work on adding wallet UI

app/lib/models/wallet.dart

@@ -20,3 +20,12 @@ class Wallet {
   String tfchainBalance;
   final WalletType type;
 }
+
+class SimpleWallet {
+  SimpleWallet({
+    required this.name,
+    required this.secret,
+  });
+  final String name;
+  final String secret;
+}

app/lib/screens/wallet_screen.dart

@@ -1,9 +1,12 @@
 import 'dart:ui';
 
+import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
+import 'package:threebotlogin/helpers/globals.dart';
 import 'package:threebotlogin/models/wallet.dart';
 import 'package:threebotlogin/services/wallet_service.dart';
+import 'package:threebotlogin/widgets/add_wallet.dart';
 import 'package:threebotlogin/widgets/layout_drawer.dart';
 import 'package:threebotlogin/widgets/wallet_card.dart';
 
@@ -50,7 +53,16 @@ class _WalletScreenState extends State<WalletScreen> {
       );
     }
 
-    return LayoutDrawer(titleText: 'Wallet', content: mainWidget);
+    return LayoutDrawer(
+      titleText: 'Wallet',
+      content: mainWidget,
+      appBarActions: [
+        IconButton(
+            // TODO: disable clicks till the wallets are loading.
+            onPressed: _openAddWalletOverlay,
+            icon: const Icon(Icons.add))
+      ],
+    );
   }
 
   listMyWallets() async {
@@ -63,4 +75,38 @@ class _WalletScreenState extends State<WalletScreen> {
       loading = false;
     });
   }
+
+  _openAddWalletOverlay() {
+    showModalBottomSheet(
+        isScrollControlled: true,
+        useSafeArea: true,
+        constraints: const BoxConstraints(maxWidth: double.infinity),
+        context: context,
+        builder: (ctx) => NewWallet(
+              onAddWallet: _addWallet,
+            ));
+  }
+
+  Future<void> _addWallet(SimpleWallet wallet) async {
+    setState(() {
+      loading = true;
+    });
+
+    final w = await loadAddWallet(wallet.name, wallet.secret);
+    wallets.add(w);
+
+    setState(() {
+      loading = false;
+    });
+  }
+}
+
+Future<Wallet> loadAddWallet(String walletName, String walletSecret) async {
+  final chainUrl = Globals().chainUrl;
+  final Wallet wallet = await compute((void _) async {
+    final wallet = await loadWallet(
+        walletName, walletSecret, WalletType.Imported, chainUrl);
+    return wallet;
+  }, null);
+  return wallet;
 }

app/lib/widgets/add_wallet.dart

@@ -0,0 +1,132 @@
+import 'package:bip39/bip39.dart';
+import 'package:flutter/cupertino.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+import 'package:threebotlogin/models/wallet.dart';
+import 'package:threebotlogin/widgets/custom_dialog.dart';
+
+class NewWallet extends StatefulWidget {
+  const NewWallet({
+    super.key,
+    required this.onAddWallet,
+  });
+  final Future<void> Function(SimpleWallet addedWallet) onAddWallet;
+
+  @override
+  State<StatefulWidget> createState() {
+    return _NewWalletState();
+  }
+}
+
+class _NewWalletState extends State<NewWallet> {
+  final _nameController = TextEditingController();
+  final _secretController = TextEditingController();
+
+  void _showDialog(String message) {
+    showDialog(
+      context: context,
+      builder: (BuildContext context) => CustomDialog(
+        image: Icons.error,
+        title: 'Invalid Input',
+        description: message,
+        actions: <Widget>[
+          TextButton(
+            child: const Text('Close'),
+            onPressed: () {
+              Navigator.pop(context);
+              setState(() {});
+            },
+          ),
+        ],
+      ),
+    );
+  }
+
+  void _validateAddSubmitData() {
+    //TODO: validate name is not used
+    if (_nameController.text.trim().isEmpty) {
+      _showDialog("Name can't be empty");
+      return;
+    }
+    if (_secretController.text.trim().isEmpty) {
+      _showDialog("Secret can't be empty");
+      return;
+    }
+    if (!validateMnemonic(_secretController.text.trim())) {
+      _showDialog('Secret is invalid');
+      return;
+    }
+    // TODO: save the wallet to pkid
+
+    widget.onAddWallet(SimpleWallet(
+        name: _nameController.text.trim(),
+        secret: _secretController.text.trim()));
+    Navigator.pop(context);
+  }
+
+  @override
+  void dispose() {
+    _nameController.dispose();
+    _secretController.dispose();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final keyboardSpace = MediaQuery.of(context).viewInsets.bottom;
+    return LayoutBuilder(builder: (ctx, constraints) {
+      return SizedBox(
+        child: SingleChildScrollView(
+          child: Padding(
+            padding: EdgeInsets.fromLTRB(16, 16, 16, keyboardSpace + 16),
+            child: Column(
+              children: [
+                TextField(
+                  style: Theme.of(context).textTheme.bodyMedium!.copyWith(
+                      color: Theme.of(context).colorScheme.onBackground,
+                      decorationColor:
+                          Theme.of(context).colorScheme.onBackground),
+                  maxLength: 50,
+                  decoration: const InputDecoration(label: Text('Name')),
+                  controller: _nameController,
+                ),
+                TextField(
+                  style: Theme.of(context).textTheme.bodyMedium!.copyWith(
+                      color: Theme.of(context).colorScheme.onBackground,
+                      decorationColor:
+                          Theme.of(context).colorScheme.onBackground),
+                  keyboardType: TextInputType.multiline,
+                  maxLines: null,
+                  decoration: const InputDecoration(
+                    label: Text('Secret'),
+                  ),
+                  controller: _secretController,
+                ),
+                const SizedBox(
+                  height: 30,
+                ),
+                Row(
+                  children: [
+                    const Spacer(),
+                    ElevatedButton(
+                        onPressed: () {
+                          Navigator.pop(context);
+                        },
+                        child: const Text('Cancel')),
+                    const SizedBox(
+                      width: 5,
+                    ),
+                    ElevatedButton(
+                        onPressed: _validateAddSubmitData,
+                        child: const Text(
+                            'Save')) //TODO: show loading when clicking on save
+                  ],
+                ),
+              ],
+            ),
+          ),
+        ),
+      );
+    });
+  }
+}