如何在SharedPreferences中保存我的復選框值？

在此，我使用了一個同意復選框，并且沒有選擇，當單擊可以選擇復選框時，值為 true，效果很好。但是我想為此添加共享首選項添加時，在選擇的單詞之后并關閉應用程式并再次重新打開，然后應該顯示最后選擇的復選框值 true。像這樣

我的代碼

import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:shared_preferences/shared_preferences.dart';

class AgreeScreen extends StatefulWidget {
  const AgreeScreen({Key? key}) : super(key: key);

  @override
  State<AgreeScreen> createState() => _AgreeScreenState();
}

class _AgreeScreenState extends State<AgreeScreen> {
  // 1st dropdown button
  @override
  void initState() {
    super.initState();
    valueAgree;
    checkValueAgree();
  }

  // // are you agree button
  String? valueAgree;
  // //boolean value (are you agree)
  bool isChecked = false;

  checkValueAgree() {
    _getDataAgree();
  }

  _saveDataAgree(bool isChecked) async {
    SharedPreferences sharedPreferences = await SharedPreferences.getInstance();
    sharedPreferences.setBool("Agree", isChecked);
  }

  _getDataAgree() async {
    SharedPreferences sharedPreferences = await SharedPreferences.getInstance();

    var result = sharedPreferences.getBool("Agree");
    if (result != null) {
      isChecked;
      setState(() {});
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: Column(
          children: [
            Padding(
              padding: const EdgeInsets.only(top: 100, left: 15.0),
              child: Row(
                children: <Widget>[
                  const Icon(
                    Icons.brightness_1,
                    color: Colors.black,
                    size: 10,
                  ),
                  const Padding(
                    padding: EdgeInsets.only(left: 15.0),
                    child: Text(
                      "Are  you agree",
                      style:
                          TextStyle(fontSize: 16, fontWeight: FontWeight.w500),
                    ),
                  ),
                  const Padding(
                    padding: EdgeInsets.only(left: 30),
                    child: Text(
                      'yes',
                      style:
                          TextStyle(fontSize: 15, fontWeight: FontWeight.bold),
                    ),
                  ),
                  Checkbox(
                    shape: RoundedRectangleBorder(
                      borderRadius: BorderRadius.circular(8.0),
                    ),
                    side: MaterialStateBorderSide.resolveWith(
                      (states) =>
                          BorderSide(width: 3.0, color: Colors.blueAccent),
                    ),
                    value: isChecked,
                    onChanged: (bool? value) {
                      setState(() {
                        isChecked = value!;
                      });
                    },
                  ),
                ],
              ),
            ),
            Padding(
              padding: const EdgeInsets.only(bottom: 0.0, top: 150),
              child: SizedBox(
                width: 160.0,
                height: 35.0,
                child: ElevatedButton(
                    style: ButtonStyle(
                      shape: MaterialStateProperty.all<RoundedRectangleBorder>(
                        RoundedRectangleBorder(
                          borderRadius: BorderRadius.circular(18.0),
                          side: const BorderSide(
                            color: Colors.blueAccent,
                          ),
                        ),
                      ),
                    ),
                    onPressed: () {
                      //do null check 1st

                      _saveDataAgree(isChecked);
                    },
                    child: const Text('next')),
              ),
            ),
          ],
        ),
      ),
    );
  }
}

uj5u.com熱心網友回復：

在這里，您需要將SharedPreferences值傳遞給isChecked，因為您Checkbox使用isChecked，您不需要 String? valueAgree將其洗掉：

_getDataAgree() async {
    SharedPreferences sharedPreferences = await SharedPreferences.getInstance();
  
    var result = sharedPreferences.getBool("Agree");
    if (result != null){
        isChecked = result;
        setState(() {});
    }
  }

并將您的更改_saveDataAgree為：

_saveDataAgree(bool isChecked) async {
    SharedPreferences sharedPreferences = await SharedPreferences.getInstance();
    sharedPreferences.setBool("Agree", isChecked);
    
  }

uj5u.com熱心網友回復：

如果您將問題保存為鍵并將選定的專案保存為值，那就很好了。

標籤：扑镖共享偏好

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