Feat: Fügt eine Dummy-Settings-Seite hinzu

lib/Pages/Settings/settings.dart

@@ -1,6 +1,202 @@
 import 'package:flutter/material.dart';
 
-class Settings extends StatelessWidget {
+class Settings extends StatefulWidget {
+  const Settings({super.key});
+
   @override
-  Widget build(final BuildContext context) => const Text('SETTINGS');
+  State<Settings> createState() => _SettingsState();
+}
+
+class _SettingsState extends State<Settings> {
+  final List<String> _accounts = <String>[
+    'Girokonto',
+    'Sparkonto',
+    'Kreditkarte',
+  ];
+
+  Future<void> _addAccount() async {
+    final TextEditingController controller = TextEditingController();
+
+    await showDialog(
+      context: context,
+      builder: (final BuildContext context) => AlertDialog(
+        title: const Text('Konto hinzufügen'),
+        content: TextField(
+          controller: controller,
+          decoration: const InputDecoration(
+            labelText: 'Kontoname',
+            border: OutlineInputBorder(),
+          ),
+          autofocus: true,
+        ),
+        actions: <Widget>[
+          TextButton(
+            onPressed: () => Navigator.pop(context),
+            child: const Text('Abbrechen'),
+          ),
+          ElevatedButton(
+            onPressed: () {
+              if (controller.text.isNotEmpty) {
+                setState(() => _accounts.add(controller.text));
+              }
+              Navigator.pop(context);
+            },
+            child: const Text('Hinzufügen'),
+          ),
+        ],
+      ),
+    );
+  }
+
+  Future<void> _renameAccount(final int index) async {
+    final TextEditingController controller = TextEditingController(
+      text: _accounts[index],
+    );
+
+    await showDialog(
+      context: context,
+      builder: (final BuildContext context) => AlertDialog(
+        title: const Text('Konto umbenennen'),
+        content: TextField(
+          controller: controller,
+          decoration: const InputDecoration(
+            labelText: 'Neuer Name',
+            border: OutlineInputBorder(),
+          ),
+          autofocus: true,
+        ),
+        actions: <Widget>[
+          TextButton(
+            onPressed: () => Navigator.pop(context),
+            child: const Text('Abbrechen'),
+          ),
+          ElevatedButton(
+            onPressed: () {
+              if (controller.text.isNotEmpty) {
+                setState(() => _accounts[index] = controller.text);
+              }
+              Navigator.pop(context);
+            },
+            child: const Text('Speichern'),
+          ),
+        ],
+      ),
+    );
+  }
+
+  Future<void> _removeAccount(final int index) async {
+    await showDialog(
+      context: context,
+      builder: (final BuildContext context) => AlertDialog(
+        title: const Text('Konto entfernen'),
+        content: Text(
+          'Möchtest du das Konto "${_accounts[index]}" wirklich löschen?',
+        ),
+        actions: <Widget>[
+          TextButton(
+            onPressed: () => Navigator.pop(context),
+            child: const Text('Abbrechen'),
+          ),
+          ElevatedButton(
+            style: ElevatedButton.styleFrom(
+              backgroundColor: Theme.of(context).colorScheme.error,
+            ),
+            onPressed: () {
+              setState(() => _accounts.removeAt(index));
+              Navigator.pop(context);
+            },
+            child: const Text('Löschen'),
+          ),
+        ],
+      ),
+    );
+  }
+
+  @override
+  Widget build(final BuildContext context) {
+    final ThemeData theme = Theme.of(context);
+
+    return Scaffold(
+      body: SafeArea(
+        child: Padding(
+          padding: const EdgeInsets.all(16),
+          child: Column(
+            crossAxisAlignment: CrossAxisAlignment.start,
+            children: <Widget>[
+              const Text(
+                'Einstellungen',
+                style: TextStyle(fontSize: 24, fontWeight: FontWeight.bold),
+              ),
+
+              const SizedBox(height: 24),
+              _accountHeader(),
+
+              const SizedBox(height: 8),
+              _accountList(),
+
+              const SizedBox(height: 8),
+              _versionNumber(theme),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+
+  Widget _accountHeader() => Row(
+    mainAxisAlignment: MainAxisAlignment.spaceBetween,
+    children: <Widget>[
+      const Text(
+        'Konten',
+        style: TextStyle(fontSize: 18, fontWeight: FontWeight.bold),
+      ),
+      IconButton(
+        onPressed: _addAccount,
+        icon: const Icon(Icons.add),
+        tooltip: 'Konto hinzufügen',
+      ),
+    ],
+  );
+
+  Widget _accountList() => Expanded(
+    child: ListView.separated(
+      itemCount: _accounts.length,
+      separatorBuilder: (_, _) => const Divider(),
+      itemBuilder: (final BuildContext context, final int index) => ListTile(
+        contentPadding: EdgeInsets.zero,
+        title: Text(_accounts[index]),
+        leading: const Icon(Icons.account_balance_wallet),
+        trailing: PopupMenuButton<String>(
+          onSelected: (final String value) async {
+            if (value == 'rename') {
+              await _renameAccount(index);
+            } else if (value == 'delete') {
+              await _removeAccount(index);
+            }
+          },
+          itemBuilder: (final BuildContext context) =>
+              const <PopupMenuEntry<String>>[
+                PopupMenuItem<String>(
+                  value: 'rename',
+                  child: Text('Umbenennen'),
+                ),
+                PopupMenuItem<String>(
+                  value: 'delete',
+                  child: Text('Entfernen'),
+                ),
+              ],
+        ),
+      ),
+    ),
+  );
+
+  Widget _versionNumber(final ThemeData theme) => Align(
+    alignment: Alignment.bottomRight,
+    child: Text(
+      'Version 0.0.0+0',
+      style: theme.textTheme.bodySmall?.copyWith(
+        color: theme.colorScheme.onSurface.withAlpha((0.6 * 255).round()),
+      ),
+    ),
+  );
 }