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Flutter 未处理的异常:无效参数(值):不得为 null

[英]Flutter Unhandled Exception: Invalid argument(s) (value): Must not be null

this method was working fine if i provide a null value it will not throw error, but after updating to flutter 2.1 now it throws an exception if i provide null value whats the best solution for this please如果我提供 null 值,则此方法工作正常,它不会引发错误,但在更新到 flutter 2.1 后,现在如果我提供 null 值,它会引发异常,请为此提供最佳解决方案

  /// Method that saves the user lang in shared preferences
  static Future<dynamic> setLanguage (value) async {
    final SharedPreferences prefs = await SharedPreferences.getInstance();
    return prefs.setString(_language, value);
  }

[ERROR:flutter/lib/ui/ui_dart_state.cc(199)] Unhandled Exception: Invalid argument(s) (value): Must not be null [错误:flutter/lib/ui/ui_dart_state.cc(199)] 未处理的异常:无效参数(值):不能是 null

E/flutter (22502): #0 ArgumentError.checkNotNull (dart:core/errors.dart:185:27) E/flutter (22502): #1 E/flutter (22502): #0 ArgumentError.checkNotNull (dart:core/errors.dart:185:27) E/flutter (22502): #1
SharedPreferences._setValue (package:shared_preferences/shared_preferences.dart:147:19) E/flutter (22502): #2 SharedPreferences.setString (package:shared_preferences/shared_preferences.dart:133:7) SharedPreferences._setValue (package:shared_preferences/shared_preferences.dart:147:19) E/flutter (22502): #2 SharedPreferences.setString (package:shared_preferences/shared_preferences.ZBB14127678960FAE97D8733Z:72EA)

Check the value then save it:检查值然后保存:

 static Future<dynamic> setLanguage (value) async {
    if (value != null){
      final SharedPreferences prefs = await SharedPreferences.getInstance();
      return prefs.setString(_language, value);
    }
   return null;
 }

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