add ba/nano wallet representative change option to wallet settings, remove coin control from ba/nano, and some other clean up

lib/pages/add_wallet_views/add_token_view/add_custom_token_view.dart

@@ -142,7 +142,7 @@ class _AddCustomTokenViewState extends ConsumerState<AddCustomTokenView> {
                   context: context,
                   message: "Looking up contract",
                 );
-                currentToken = response.value;
+                currentToken = response!.value;
                 if (currentToken != null) {
                   nameController.text = currentToken!.name;
                   symbolController.text = currentToken!.symbol;
@@ -157,7 +157,7 @@ class _AddCustomTokenViewState extends ConsumerState<AddCustomTokenView> {
                         context: context,
                         builder: (context) => StackOkDialog(
                           title: "Failed to look up token",
-                          message: response.exception?.message,
+                          message: response!.exception?.message,
                         ),
                       ),
                     );

lib/pages/settings_views/global_settings_view/appearance_settings/sub_widgets/install_theme_from_file_dialog.dart

@@ -164,7 +164,7 @@ class _InstallThemeFromFileDialogState
                     );
                     if (mounted) {
                       Navigator.of(context).pop();
-                      if (!result) {
+                      if (!result!) {
                         unawaited(
                           showDialog(
                             context: context,

lib/pages/settings_views/global_settings_view/appearance_settings/sub_widgets/stack_theme_card.dart

@@ -72,11 +72,11 @@ class _StackThemeCardState extends ConsumerState<StackThemeCard> {
   }
 
   Future<void> _downloadPressed() async {
-    final result = await showLoading(
+    final result = (await showLoading(
       whileFuture: _downloadAndInstall(),
       context: context,
       message: "Downloading and installing theme...",
-    );
+    ))!;
 
     if (mounted) {
       final message = result

lib/pages/settings_views/wallet_settings_view/wallet_settings_view.dart

@@ -20,11 +20,12 @@ import 'package:stackwallet/pages/home_view/home_view.dart';
 import 'package:stackwallet/pages/pinpad_views/lock_screen_view.dart';
 import 'package:stackwallet/pages/settings_views/global_settings_view/advanced_views/debug_view.dart';
 import 'package:stackwallet/pages/settings_views/global_settings_view/syncing_preferences_views/syncing_preferences_view.dart';
-import 'package:stackwallet/pages/settings_views/global_settings_view/xpub_view.dart';
 import 'package:stackwallet/pages/settings_views/sub_widgets/settings_list_button.dart';
 import 'package:stackwallet/pages/settings_views/wallet_settings_view/wallet_backup_views/wallet_backup_view.dart';
 import 'package:stackwallet/pages/settings_views/wallet_settings_view/wallet_network_settings_view/wallet_network_settings_view.dart';
+import 'package:stackwallet/pages/settings_views/wallet_settings_view/wallet_settings_wallet_settings/change_representative_view.dart';
 import 'package:stackwallet/pages/settings_views/wallet_settings_view/wallet_settings_wallet_settings/wallet_settings_wallet_settings_view.dart';
+import 'package:stackwallet/pages/settings_views/wallet_settings_view/wallet_settings_wallet_settings/xpub_view.dart';
 import 'package:stackwallet/providers/global/wallets_provider.dart';
 import 'package:stackwallet/providers/ui/transaction_filter_provider.dart';
 import 'package:stackwallet/route_generator.dart';
@@ -231,7 +232,7 @@ class _WalletSettingsViewState extends ConsumerState<WalletSettingsView> {
                                             .mnemonic;
 
                                         if (mounted) {
-                                          Navigator.push(
+                                          await Navigator.push(
                                             context,
                                             RouteGenerator.getRoute(
                                               shouldUseMaterialRoute:
@@ -305,6 +306,25 @@ class _WalletSettingsViewState extends ConsumerState<WalletSettingsView> {
                                       );
                                     },
                                   ),
+                                if (coin == Coin.nano || coin == Coin.banano)
+                                  const SizedBox(
+                                    height: 8,
+                                  ),
+                                if (coin == Coin.nano || coin == Coin.banano)
+                                  Consumer(
+                                    builder: (_, ref, __) {
+                                      return SettingsListButton(
+                                        iconAssetName: Assets.svg.eye,
+                                        title: "Change representative",
+                                        onPressed: () {
+                                          Navigator.of(context).pushNamed(
+                                            ChangeRepresentativeView.routeName,
+                                            arguments: widget.walletId,
+                                          );
+                                        },
+                                      );
+                                    },
+                                  ),
                                 const SizedBox(
                                   height: 8,
                                 ),
@@ -434,18 +454,20 @@ class _EpiBoxInfoFormState extends ConsumerState<EpicBoxInfoForm> {
           TextButton(
             onPressed: () async {
               try {
-                wallet.updateEpicboxConfig(
+                await wallet.updateEpicboxConfig(
                   hostController.text,
                   int.parse(portController.text),
                 );
-                showFloatingFlushBar(
+                if (mounted) {
-                  context: context,
+                  await showFloatingFlushBar(
-                  message: "Epicbox info saved!",
+                    context: context,
-                  type: FlushBarType.success,
+                    message: "Epicbox info saved!",
-                );
+                    type: FlushBarType.success,
-                wallet.refresh();
+                  );
+                }
+                unawaited(wallet.refresh());
               } catch (e) {
-                showFloatingFlushBar(
+                await showFloatingFlushBar(
                   context: context,
                   message: "Failed to save epicbox info: $e",
                   type: FlushBarType.warning,

lib/pages/settings_views/wallet_settings_view/wallet_settings_wallet_settings/change_representative_view.dart

@@ -0,0 +1,367 @@
+/*
+ * This file is part of Stack Wallet.
+ *
+ * Copyright (c) 2023 Cypher Stack
+ * All Rights Reserved.
+ * The code is distributed under GPLv3 license, see LICENSE file for details.
+ * Generated by Cypher Stack on 2023-05-26
+ *
+ */
+
+import 'dart:async';
+
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:flutter_svg/svg.dart';
+import 'package:stackwallet/notifications/show_flush_bar.dart';
+import 'package:stackwallet/providers/global/wallets_provider.dart';
+import 'package:stackwallet/services/coins/banano/banano_wallet.dart';
+import 'package:stackwallet/services/coins/nano/nano_wallet.dart';
+import 'package:stackwallet/themes/stack_colors.dart';
+import 'package:stackwallet/utilities/assets.dart';
+import 'package:stackwallet/utilities/clipboard_interface.dart';
+import 'package:stackwallet/utilities/constants.dart';
+import 'package:stackwallet/utilities/enums/coin_enum.dart';
+import 'package:stackwallet/utilities/show_loading.dart';
+import 'package:stackwallet/utilities/text_styles.dart';
+import 'package:stackwallet/utilities/util.dart';
+import 'package:stackwallet/widgets/background.dart';
+import 'package:stackwallet/widgets/conditional_parent.dart';
+import 'package:stackwallet/widgets/custom_buttons/app_bar_icon_button.dart';
+import 'package:stackwallet/widgets/desktop/desktop_dialog.dart';
+import 'package:stackwallet/widgets/desktop/desktop_dialog_close_button.dart';
+import 'package:stackwallet/widgets/desktop/primary_button.dart';
+import 'package:stackwallet/widgets/icon_widgets/x_icon.dart';
+import 'package:stackwallet/widgets/loading_indicator.dart';
+import 'package:stackwallet/widgets/rounded_white_container.dart';
+import 'package:stackwallet/widgets/stack_text_field.dart';
+import 'package:stackwallet/widgets/textfield_icon_button.dart';
+
+class ChangeRepresentativeView extends ConsumerStatefulWidget {
+  const ChangeRepresentativeView({
+    Key? key,
+    required this.walletId,
+    this.clipboardInterface = const ClipboardWrapper(),
+  }) : super(key: key);
+
+  final String walletId;
+  final ClipboardInterface clipboardInterface;
+
+  static const String routeName = "/changeRepresentative";
+
+  @override
+  ConsumerState<ChangeRepresentativeView> createState() => _XPubViewState();
+}
+
+class _XPubViewState extends ConsumerState<ChangeRepresentativeView> {
+  final _textController = TextEditingController();
+  final _textFocusNode = FocusNode();
+  final bool isDesktop = Util.isDesktop;
+
+  late ClipboardInterface _clipboardInterface;
+
+  String? representative;
+
+  Future<String> loadRepresentative() async {
+    final manager =
+        ref.read(walletsChangeNotifierProvider).getManager(widget.walletId);
+
+    if (manager.coin == Coin.nano) {
+      return (manager.wallet as NanoWallet).getCurrentRepresentative();
+    } else if (manager.coin == Coin.banano) {
+      return (manager.wallet as BananoWallet).getCurrentRepresentative();
+    }
+    throw Exception("Unsupported wallet attempted to show representative!");
+  }
+
+  Future<void> _save() async {
+    final manager =
+        ref.read(walletsChangeNotifierProvider).getManager(widget.walletId);
+
+    final changeFuture = manager.coin == Coin.nano
+        ? (manager.wallet as NanoWallet).changeRepresentative
+        : (manager.wallet as BananoWallet).changeRepresentative;
+
+    final result = await showLoading(
+        whileFuture: changeFuture(_textController.text),
+        context: context,
+        message: "Updating representative...",
+        onException: (ex) {
+          String msg = ex.toString();
+          while (msg.isNotEmpty && msg.startsWith("Exception:")) {
+            msg = msg.substring(10).trim();
+          }
+          showFloatingFlushBar(
+            type: FlushBarType.warning,
+            message: msg,
+            context: context,
+          );
+        });
+
+    if (mounted) {
+      if (result != null && result) {
+        setState(() {
+          representative = _textController.text;
+          _textController.text = "";
+        });
+        await showFloatingFlushBar(
+          type: FlushBarType.success,
+          message: "Representative changed",
+          context: context,
+        );
+      }
+    }
+  }
+
+  @override
+  void initState() {
+    _clipboardInterface = widget.clipboardInterface;
+
+    super.initState();
+  }
+
+  @override
+  void dispose() {
+    _textController.dispose();
+    _textFocusNode.dispose();
+    super.dispose();
+  }
+
+  Future<void> _copy() async {
+    await _clipboardInterface
+        .setData(ClipboardData(text: representative ?? ""));
+    if (mounted) {
+      unawaited(showFloatingFlushBar(
+        type: FlushBarType.info,
+        message: "Copied to clipboard",
+        iconAsset: Assets.svg.copy,
+        context: context,
+      ));
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return ConditionalParent(
+      condition: !isDesktop,
+      builder: (child) => Background(
+        child: SafeArea(
+          child: Scaffold(
+            backgroundColor:
+                Theme.of(context).extension<StackColors>()!.background,
+            appBar: AppBar(
+              leading: AppBarBackButton(
+                onPressed: () async {
+                  Navigator.of(context).pop();
+                },
+              ),
+              title: Text(
+                "Wallet representative",
+                style: STextStyles.navBarTitle(context),
+              ),
+              actions: [
+                Padding(
+                  padding: const EdgeInsets.all(10),
+                  child: AspectRatio(
+                    aspectRatio: 1,
+                    child: AppBarIconButton(
+                      color: Theme.of(context)
+                          .extension<StackColors>()!
+                          .background,
+                      shadows: const [],
+                      icon: SvgPicture.asset(
+                        Assets.svg.copy,
+                        width: 24,
+                        height: 24,
+                        color: Theme.of(context)
+                            .extension<StackColors>()!
+                            .topNavIconPrimary,
+                      ),
+                      onPressed: () {
+                        if (representative != null) {
+                          _copy();
+                        }
+                      },
+                    ),
+                  ),
+                ),
+              ],
+            ),
+            body: Padding(
+              padding: const EdgeInsets.only(
+                top: 12,
+                left: 16,
+                right: 16,
+              ),
+              child: child,
+            ),
+          ),
+        ),
+      ),
+      child: ConditionalParent(
+        condition: isDesktop,
+        builder: (child) => DesktopDialog(
+          maxWidth: 600,
+          maxHeight: double.infinity,
+          child: Column(
+            children: [
+              Row(
+                mainAxisAlignment: MainAxisAlignment.spaceBetween,
+                children: [
+                  Padding(
+                    padding: const EdgeInsets.only(
+                      left: 32,
+                    ),
+                    child: Text(
+                      "${ref.watch(walletsChangeNotifierProvider.select((value) => value.getManager(widget.walletId).walletName))} xPub",
+                      style: STextStyles.desktopH2(context),
+                    ),
+                  ),
+                  DesktopDialogCloseButton(
+                    onPressedOverride: Navigator.of(
+                      context,
+                      rootNavigator: true,
+                    ).pop,
+                  ),
+                ],
+              ),
+              AnimatedSize(
+                duration: const Duration(
+                  milliseconds: 150,
+                ),
+                child: Padding(
+                  padding: const EdgeInsets.fromLTRB(32, 0, 32, 32),
+                  child: child,
+                ),
+              ),
+            ],
+          ),
+        ),
+        child: Column(
+          children: [
+            if (isDesktop) const SizedBox(height: 44),
+            ConditionalParent(
+              condition: !isDesktop,
+              builder: (child) => Expanded(
+                child: child,
+              ),
+              child: FutureBuilder(
+                future: loadRepresentative(),
+                builder: (context, AsyncSnapshot<String> snapshot) {
+                  if (snapshot.connectionState == ConnectionState.done &&
+                      snapshot.hasData) {
+                    representative = snapshot.data!;
+                  }
+
+                  const height = 600.0;
+                  Widget child;
+                  if (representative == null) {
+                    child = const SizedBox(
+                      key: Key("loadingRepresentative"),
+                      height: height,
+                      child: Center(
+                        child: LoadingIndicator(
+                          width: 100,
+                        ),
+                      ),
+                    );
+                  } else {
+                    child = Column(
+                      children: [
+                        RoundedWhiteContainer(
+                          child: Column(
+                            crossAxisAlignment: CrossAxisAlignment.start,
+                            children: [
+                              Text(
+                                representative!,
+                                style: STextStyles.itemSubtitle(context),
+                              ),
+                            ],
+                          ),
+                        ),
+                        const SizedBox(
+                          height: 24,
+                        ),
+                        ClipRRect(
+                          borderRadius: BorderRadius.circular(
+                            Constants.size.circularBorderRadius,
+                          ),
+                          child: TextField(
+                            autocorrect: Util.isDesktop ? false : true,
+                            enableSuggestions: Util.isDesktop ? false : true,
+                            controller: _textController,
+                            style: isDesktop
+                                ? STextStyles.desktopTextExtraSmall(context)
+                                    .copyWith(
+                                    color: Theme.of(context)
+                                        .extension<StackColors>()!
+                                        .textFieldActiveText,
+                                    height: 1.8,
+                                  )
+                                : STextStyles.field(context),
+                            focusNode: _textFocusNode,
+                            decoration: standardInputDecoration(
+                              "Enter new representative",
+                              _textFocusNode,
+                              context,
+                              desktopMed: isDesktop,
+                            ).copyWith(
+                              contentPadding: isDesktop
+                                  ? const EdgeInsets.only(
+                                      left: 16,
+                                      top: 11,
+                                      bottom: 12,
+                                      right: 5,
+                                    )
+                                  : null,
+                              suffixIcon: _textController.text.isNotEmpty
+                                  ? Padding(
+                                      padding: const EdgeInsets.only(right: 0),
+                                      child: UnconstrainedBox(
+                                        child: Row(
+                                          children: [
+                                            TextFieldIconButton(
+                                              child: const XIcon(),
+                                              onTap: () async {
+                                                setState(() {
+                                                  _textController.text = "";
+                                                });
+                                              },
+                                            ),
+                                          ],
+                                        ),
+                                      ),
+                                    )
+                                  : null,
+                            ),
+                          ),
+                        ),
+                        if (!isDesktop) const Spacer(),
+                        PrimaryButton(
+                          label: "Save",
+                          onPressed: _save,
+                        ),
+                        if (!isDesktop)
+                          const SizedBox(
+                            height: 16,
+                          ),
+                      ],
+                    );
+                  }
+
+                  return AnimatedSwitcher(
+                    duration: const Duration(
+                      milliseconds: 200,
+                    ),
+                    child: child,
+                  );
+                },
+              ),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}

lib/pages/token_view/sub_widgets/my_token_select_item.dart

@@ -100,7 +100,7 @@ class _MyTokenSelectItemState extends ConsumerState<MyTokenSelectItem> {
       message: "Loading ${widget.token.name}",
     );
 
-    if (!success) {
+    if (!success!) {
       return;
     }
 

lib/pages_desktop_specific/my_stack_view/wallet_view/sub_widgets/wallet_options_button.dart

@@ -13,7 +13,7 @@ import 'dart:async';
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:flutter_svg/svg.dart';
-import 'package:stackwallet/pages/settings_views/global_settings_view/xpub_view.dart';
+import 'package:stackwallet/pages/settings_views/wallet_settings_view/wallet_settings_wallet_settings/xpub_view.dart';
 import 'package:stackwallet/pages_desktop_specific/addresses/desktop_wallet_addresses_view.dart';
 import 'package:stackwallet/pages_desktop_specific/my_stack_view/wallet_view/sub_widgets/desktop_delete_wallet_dialog.dart';
 import 'package:stackwallet/providers/providers.dart';

lib/route_generator.dart

@@ -103,14 +103,15 @@ import 'package:stackwallet/pages/settings_views/global_settings_view/support_vi
 import 'package:stackwallet/pages/settings_views/global_settings_view/syncing_preferences_views/syncing_options_view.dart';
 import 'package:stackwallet/pages/settings_views/global_settings_view/syncing_preferences_views/syncing_preferences_view.dart';
 import 'package:stackwallet/pages/settings_views/global_settings_view/syncing_preferences_views/wallet_syncing_options_view.dart';
-import 'package:stackwallet/pages/settings_views/global_settings_view/xpub_view.dart';
 import 'package:stackwallet/pages/settings_views/wallet_settings_view/wallet_backup_views/wallet_backup_view.dart';
 import 'package:stackwallet/pages/settings_views/wallet_settings_view/wallet_network_settings_view/wallet_network_settings_view.dart';
 import 'package:stackwallet/pages/settings_views/wallet_settings_view/wallet_settings_view.dart';
+import 'package:stackwallet/pages/settings_views/wallet_settings_view/wallet_settings_wallet_settings/change_representative_view.dart';
 import 'package:stackwallet/pages/settings_views/wallet_settings_view/wallet_settings_wallet_settings/delete_wallet_recovery_phrase_view.dart';
 import 'package:stackwallet/pages/settings_views/wallet_settings_view/wallet_settings_wallet_settings/delete_wallet_warning_view.dart';
 import 'package:stackwallet/pages/settings_views/wallet_settings_view/wallet_settings_wallet_settings/rename_wallet_view.dart';
 import 'package:stackwallet/pages/settings_views/wallet_settings_view/wallet_settings_wallet_settings/wallet_settings_wallet_settings_view.dart';
+import 'package:stackwallet/pages/settings_views/wallet_settings_view/wallet_settings_wallet_settings/xpub_view.dart';
 import 'package:stackwallet/pages/stack_privacy_calls.dart';
 import 'package:stackwallet/pages/token_view/my_tokens_view.dart';
 import 'package:stackwallet/pages/token_view/token_contract_details_view.dart';
@@ -564,6 +565,20 @@ class RouteGenerator {
         }
         return _routeError("${settings.name} invalid args: ${args.toString()}");
 
+      case ChangeRepresentativeView.routeName:
+        if (args is String) {
+          return getRoute(
+            shouldUseMaterialRoute: useMaterialPageRoute,
+            builder: (_) => ChangeRepresentativeView(
+              walletId: args,
+            ),
+            settings: RouteSettings(
+              name: settings.name,
+            ),
+          );
+        }
+        return _routeError("${settings.name} invalid args: ${args.toString()}");
+
       case AppearanceSettingsView.routeName:
         return getRoute(
             shouldUseMaterialRoute: useMaterialPageRoute,

lib/services/coins/banano/banano_wallet.dart

@@ -14,9 +14,9 @@ import 'package:stackwallet/services/event_bus/events/global/node_connection_sta
 import 'package:stackwallet/services/event_bus/events/global/updated_in_background_event.dart';
 import 'package:stackwallet/services/event_bus/events/global/wallet_sync_status_changed_event.dart';
 import 'package:stackwallet/services/event_bus/global_event_bus.dart';
-import 'package:stackwallet/services/mixins/coin_control_interface.dart';
 import 'package:stackwallet/services/mixins/wallet_cache.dart';
 import 'package:stackwallet/services/mixins/wallet_db.dart';
+import 'package:stackwallet/services/nano_api.dart';
 import 'package:stackwallet/services/node_service.dart';
 import 'package:stackwallet/services/transaction_notification_tracker.dart';
 import 'package:stackwallet/utilities/amount/amount.dart';
@@ -32,8 +32,7 @@ const int MINIMUM_CONFIRMATIONS = 1;
 const String DEFAULT_REPRESENTATIVE =
     "ban_1ka1ium4pfue3uxtntqsrib8mumxgazsjf58gidh1xeo5te3whsq8z476goo";
 
-class BananoWallet extends CoinServiceAPI
+class BananoWallet extends CoinServiceAPI with WalletCache, WalletDB {
-    with WalletCache, WalletDB, CoinControlInterface {
   BananoWallet({
     required String walletId,
     required String walletName,
@@ -925,4 +924,51 @@ class BananoWallet extends CoinServiceAPI
     );
     await updateCachedChainHeight(height ?? 0);
   }
+
+  Future<String> getCurrentRepresentative() async {
+    final serverURI = Uri.parse(getCurrentNode().host);
+    final address = await currentReceivingAddress;
+
+    final response = await NanoAPI.getAccountInfo(
+      server: serverURI,
+      representative: true,
+      account: address,
+    );
+
+    return response.accountInfo?.representative ?? DEFAULT_REPRESENTATIVE;
+  }
+
+  Future<bool> changeRepresentative(String newRepresentative) async {
+    try {
+      final serverURI = Uri.parse(getCurrentNode().host);
+      final balance = this.balance.spendable.raw.toString();
+      final String privateKey = await getPrivateKeyFromMnemonic();
+      final address = await currentReceivingAddress;
+
+      final response = await NanoAPI.getAccountInfo(
+        server: serverURI,
+        representative: true,
+        account: address,
+      );
+
+      if (response.accountInfo == null) {
+        throw response.exception ?? Exception("Failed to get account info");
+      }
+
+      final work = await requestWork(response.accountInfo!.frontier);
+
+      return await NanoAPI.changeRepresentative(
+        server: serverURI,
+        accountType: NanoAccountType.BANANO,
+        account: address,
+        newRepresentative: newRepresentative,
+        previousBlock: response.accountInfo!.frontier,
+        balance: balance,
+        privateKey: privateKey,
+        work: work!,
+      );
+    } catch (_) {
+      rethrow;
+    }
+  }
 }

lib/services/coins/nano/nano_wallet.dart

@@ -24,9 +24,9 @@ import 'package:stackwallet/services/event_bus/events/global/node_connection_sta
 import 'package:stackwallet/services/event_bus/events/global/updated_in_background_event.dart';
 import 'package:stackwallet/services/event_bus/events/global/wallet_sync_status_changed_event.dart';
 import 'package:stackwallet/services/event_bus/global_event_bus.dart';
-import 'package:stackwallet/services/mixins/coin_control_interface.dart';
 import 'package:stackwallet/services/mixins/wallet_cache.dart';
 import 'package:stackwallet/services/mixins/wallet_db.dart';
+import 'package:stackwallet/services/nano_api.dart';
 import 'package:stackwallet/services/node_service.dart';
 import 'package:stackwallet/services/transaction_notification_tracker.dart';
 import 'package:stackwallet/utilities/amount/amount.dart';
@@ -42,8 +42,7 @@ const int MINIMUM_CONFIRMATIONS = 1;
 const String DEFAULT_REPRESENTATIVE =
     "nano_38713x95zyjsqzx6nm1dsom1jmm668owkeb9913ax6nfgj15az3nu8xkx579";
 
-class NanoWallet extends CoinServiceAPI
+class NanoWallet extends CoinServiceAPI with WalletCache, WalletDB {
-    with WalletCache, WalletDB, CoinControlInterface {
   NanoWallet({
     required String walletId,
     required String walletName,
@@ -937,4 +936,51 @@ class NanoWallet extends CoinServiceAPI
     );
     await updateCachedChainHeight(height ?? 0);
   }
+
+  Future<String> getCurrentRepresentative() async {
+    final serverURI = Uri.parse(getCurrentNode().host);
+    final address = await currentReceivingAddress;
+
+    final response = await NanoAPI.getAccountInfo(
+      server: serverURI,
+      representative: true,
+      account: address,
+    );
+
+    return response.accountInfo?.representative ?? DEFAULT_REPRESENTATIVE;
+  }
+
+  Future<bool> changeRepresentative(String newRepresentative) async {
+    try {
+      final serverURI = Uri.parse(getCurrentNode().host);
+      final balance = this.balance.spendable.raw.toString();
+      final String privateKey = await getPrivateKeyFromMnemonic();
+      final address = await currentReceivingAddress;
+
+      final response = await NanoAPI.getAccountInfo(
+        server: serverURI,
+        representative: true,
+        account: address,
+      );
+
+      if (response.accountInfo == null) {
+        throw response.exception ?? Exception("Failed to get account info");
+      }
+
+      final work = await requestWork(response.accountInfo!.frontier);
+
+      return await NanoAPI.changeRepresentative(
+        server: serverURI,
+        accountType: NanoAccountType.NANO,
+        account: address,
+        newRepresentative: newRepresentative,
+        previousBlock: response.accountInfo!.frontier,
+        balance: balance,
+        privateKey: privateKey,
+        work: work!,
+      );
+    } catch (_) {
+      rethrow;
+    }
+  }
 }

lib/services/nano_api.dart

@@ -0,0 +1,130 @@
+import 'dart:convert';
+
+import 'package:http/http.dart' as http;
+import 'package:nanodart/nanodart.dart';
+
+class NanoAPI {
+  static Future<
+      ({
+        NAccountInfo? accountInfo,
+        Exception? exception,
+      })> getAccountInfo({
+    required Uri server,
+    required bool representative,
+    required String account,
+  }) async {
+    NAccountInfo? accountInfo;
+    Exception? exception;
+
+    try {
+      final response = await http.post(
+        server,
+        headers: {
+          "Content-Type": "application/json",
+        },
+        body: jsonEncode({
+          "action": "account_info",
+          "representative": "true",
+          "account": account,
+        }),
+      );
+
+      final map = jsonDecode(response.body);
+
+      if (map is Map && map["error"] != null) {
+        throw Exception(map["error"].toString());
+      }
+
+      accountInfo = NAccountInfo(
+        frontier: map["frontier"] as String,
+        representative: map["representative"] as String,
+      );
+    } on Exception catch (e) {
+      exception = e;
+    } catch (e) {
+      exception = Exception(e.toString());
+    }
+
+    return (accountInfo: accountInfo, exception: exception);
+  }
+
+  static Future<bool> changeRepresentative({
+    required Uri server,
+    required int accountType,
+    required String account,
+    required String newRepresentative,
+    required String previousBlock,
+    required String balance,
+    required String privateKey,
+    required String work,
+  }) async {
+    Map<String, String> block = {
+      "type": "state",
+      "account": account,
+      "previous": previousBlock,
+      "representative": newRepresentative,
+      "balance": balance,
+      "link":
+          "0000000000000000000000000000000000000000000000000000000000000000",
+      "work": work,
+    };
+
+    final String hash;
+
+    try {
+      hash = NanoBlocks.computeStateHash(
+        accountType,
+        account,
+        previousBlock,
+        newRepresentative,
+        BigInt.parse(balance),
+        block["link"] as String,
+      );
+    } catch (e) {
+      if (e is RangeError) {
+        throw Exception("Invalid representative format");
+      }
+      rethrow;
+    }
+
+    final signature = NanoSignatures.signBlock(hash, privateKey);
+
+    block["signature"] = signature;
+
+    final map = await postBlock(server: server, block: block);
+
+    if (map is Map && map["error"] != null) {
+      throw Exception(map["error"].toString());
+    }
+
+    return map["error"] == null;
+  }
+
+  // TODO: GET RID OF DYNAMIC AND USED TYPED DATA
+  static Future<dynamic> postBlock({
+    required Uri server,
+    required Map<String, dynamic> block,
+  }) async {
+    final response = await http.post(
+      server,
+      headers: {
+        "Content-Type": "application/json",
+      },
+      body: jsonEncode({
+        "action": "process",
+        "json_block": "true",
+        "subtype": "change",
+        "block": block,
+      }),
+    );
+
+    return jsonDecode(response.body);
+  }
+}
+
+class NAccountInfo {
+  final String frontier;
+  final String representative;
+
+  NAccountInfo({required this.frontier, required this.representative});
+}

lib/utilities/show_loading.dart

@@ -12,15 +12,17 @@ import 'dart:async';
 
 import 'package:flutter/material.dart';
 import 'package:stackwallet/themes/stack_colors.dart';
+import 'package:stackwallet/utilities/logger.dart';
 import 'package:stackwallet/widgets/custom_loading_overlay.dart';
 
-Future<T> showLoading<T>({
+Future<T?> showLoading<T>({
   required Future<T> whileFuture,
   required BuildContext context,
   required String message,
   String? subMessage,
   bool isDesktop = false,
   bool opaqueBG = false,
+  void Function(Exception)? onException,
 }) async {
   unawaited(
     showDialog<void>(
@@ -43,10 +45,24 @@ Future<T> showLoading<T>({
     ),
   );
 
-  final result = await whileFuture;
+  Exception? ex;
+  T? result;
+
+  try {
+    result = await whileFuture;
+  } catch (e, s) {
+    Logging.instance.log(
+      "showLoading caught: $e\n$s",
+      level: LogLevel.Warning,
+    );
+    ex = e is Exception ? e : Exception(e.toString());
+  }
 
   if (context.mounted) {
     Navigator.of(context, rootNavigator: isDesktop).pop();
+    if (ex != null) {
+      onException?.call(ex);
+    }
   }
 
   return result;

lib/widgets/wallet_card.dart

@@ -140,7 +140,7 @@ class SimpleWalletCard extends ConsumerWidget {
           isDesktop: Util.isDesktop,
         );
 
-        if (!success) {
+        if (!success!) {
           // TODO: show error dialog here?
           Logging.instance.log(
             "Failed to load token wallet for $contract",