feat: 首页UI，搜索，我的UI

lib/tools/util/search_history_util.dart

@@ -0,0 +1,63 @@
+import 'dart:convert';
+
+import 'package:novyronst/tools/util/sp_tool.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+
+/// 本地搜索历史（SharedPreferences），key 与 [AppSp] 规则一致（`.search.history`）。
+class SearchHistoryUtil {
+  SearchHistoryUtil._();
+
+  static const String _storageKey = 'search.history';
+  static const int _maxHistory = 20;
+
+  static Future<List<String>> _readList(SharedPreferences prefs) async {
+    final raw = prefs.getString(_storageKey);
+    if (raw == null || raw.isEmpty) return [];
+    try {
+      final decoded = jsonDecode(raw);
+      if (decoded is! List) return [];
+      return decoded.map((e) => e.toString()).where((s) => s.isNotEmpty).toList();
+    } catch (_) {
+      return [];
+    }
+  }
+
+  static Future<void> _writeList(SharedPreferences prefs, List<String> list) async {
+    await prefs.setString(_storageKey, jsonEncode(list));
+  }
+
+  /// 查询搜索历史列表（新记录在前）。
+  static Future<List<String>> getSearchList() async {
+    final prefs = await SpTool.getInstance();
+    return _readList(prefs);
+  }
+
+  /// 添加一条搜索；去重、去空白，并移到最前。
+  static Future<void> addSearch(String keyword) async {
+    final q = keyword.trim();
+    if (q.isEmpty) return;
+
+    final prefs = await SpTool.getInstance();
+    final list = await _readList(prefs);
+    list.removeWhere((e) => e == q);
+    list.insert(0, q);
+    if (list.length > _maxHistory) {
+      list.removeRange(_maxHistory, list.length);
+    }
+    await _writeList(prefs, list);
+  }
+
+  /// 删除单条搜索记录。
+  static Future<void> deleteSearch(String keyword) async {
+    final prefs = await SpTool.getInstance();
+    final list = await _readList(prefs);
+    list.removeWhere((e) => e == keyword);
+    await _writeList(prefs, list);
+  }
+
+  /// 清空全部搜索历史。
+  static Future<void> clearAllSearch() async {
+    final prefs = await SpTool.getInstance();
+    await prefs.remove(_storageKey);
+  }
+}

lib/tools/util/sp_tool.dart

@@ -0,0 +1,57 @@
+
+import 'package:shared_preferences/shared_preferences.dart';
+
+
+class SpTool {
+  static SharedPreferences? _instance;
+  static final String _basePrefix = "app.";
+  static Future<SharedPreferences>? _instanceFuture;
+
+  static Future<SharedPreferences> getInstance() {
+    if (_instance != null) {
+      return Future.value(_instance);
+    }
+
+    _instanceFuture ??= SharedPreferences.getInstance().then((prefs) {
+      _instance = prefs;
+      return prefs;
+    });
+
+    return _instanceFuture!;
+  }
+
+  void setString(String key, String value) async {
+    final prefs = await getInstance();
+    prefs.setString("$_basePrefix$key", value);
+  }
+
+  Future<String> getString(String key) async {
+    final prefs = await getInstance();
+    return prefs.getString("$_basePrefix$key") ?? '';
+  }
+
+  void setBool(String key, bool value) async {
+    final prefs = await getInstance();
+    prefs.setBool("$_basePrefix$key", value);
+  }
+
+  Future<bool> getBool(String key) async {
+    final prefs = await getInstance();
+    return prefs.getBool("$_basePrefix$key") ?? false;
+  }
+
+  void setInt(String key, int value) async {
+    final prefs = await getInstance();
+    prefs.setInt("$_basePrefix$key", value);
+  }
+
+  Future<int> getInt(String key) async {
+    final prefs = await getInstance();
+    return prefs.getInt("$_basePrefix$key") ?? 0;
+  }
+
+  void deleteKey(String key) async {
+    final prefs = await getInstance();
+    prefs.remove("$_basePrefix$key");
+  }
+}