From b0ef478e990b05991cb9c65c60baf1ec00a86f48 Mon Sep 17 00:00:00 2001
From: JingChiang <ltesr125124015@gmail.com>
Date: Tue, 3 Sep 2024 00:02:38 +0800
Subject: [PATCH] =?UTF-8?q?feat:=20=E6=96=B0=E5=A2=9E=E8=87=AA=E5=8B=95?=
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利用share perference 套件儲存使用者資料
在開啟時自動尋找是否有儲存及登入後儲存資料進share preference
---
 lib/main.dart | 26 ++++++++++++++++++++++++++
 pubspec.yaml  |  1 +
 2 files changed, 27 insertions(+)

diff --git a/lib/main.dart b/lib/main.dart
index 9ade207..5c192ad 100644
--- a/lib/main.dart
+++ b/lib/main.dart
@@ -1,5 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter/rendering.dart';
+import 'package:shared_preferences/shared_preferences.dart';
 import 'package:topic/HomePage.dart';
 import 'package:mysql_client/mysql_client.dart';
 import 'package:topic/RegisterPage.dart';
@@ -22,6 +23,7 @@ class _LoginPageState extends State<LoginPage> {
   void initState() {//初始化
     super.initState();
     _fetchData();//連資料庫
+    _CheckPreLoginInfo();//確定有先前有無登入
   }
 
   void _fetchData() async {
@@ -40,6 +42,29 @@ class _LoginPageState extends State<LoginPage> {
     await conn.connect();
   }
 
+  void _CheckPreLoginInfo() async{
+    SharedPreferences prefs = await SharedPreferences.getInstance();
+    //get user data from share preference else set empty to check not login before
+    String loginUserEmail = prefs.getString("email") ?? "";
+    //replace screen to HomePage if there are previous data in share preference
+    if(loginUserEmail != ""){
+      Navigator.pushReplacement(
+        context,
+        MaterialPageRoute(
+          builder: (context) => HomePage(
+            email: loginUserEmail,
+          ),
+        ),
+      );
+    }
+  }
+
+  void _setLoginInfo(String email) async{
+    //save user email into share preference to let app can auto login next open
+    SharedPreferences prefs = await SharedPreferences.getInstance();
+    prefs.setString("email", email);
+  }
+
   @override
   Widget build(BuildContext context) {
     debugPaintSizeEnabled=false;
@@ -180,6 +205,7 @@ class _LoginPageState extends State<LoginPage> {
         _emailController.clear();
         _ageController.clear();
         // 如果找到匹配的帳號，登入成功，跳轉到主頁
+        _setLoginInfo(email);
         Navigator.pushReplacement(
           context,
           MaterialPageRoute(
diff --git a/pubspec.yaml b/pubspec.yaml
index a00dd68..ff32113 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -41,6 +41,7 @@ dependencies:
   http: ^1.2.2
   webview_flutter: ^4.8.0
   persistent_bottom_nav_bar_v2: ^5.3.0
+  shared_preferences: ^2.2.3
 
 dev_dependencies:
   flutter_test: