feat: 新增密碼輸入匡顯示原文按鈕

lib/main.dart

@@ -19,6 +19,7 @@ class LoginPage extends StatefulWidget {//ful會改變
 class _LoginPageState extends State<LoginPage> {
   final TextEditingController _emailController = TextEditingController();
   final TextEditingController _ageController = TextEditingController();
+  bool _passwordNotVisible = true;
 
   @override
   void initState() {//初始化
@@ -116,9 +117,21 @@ class _LoginPageState extends State<LoginPage> {
                       decoration: InputDecoration(
                         border: OutlineInputBorder(),
                         prefixIcon: Icon(Icons.lock_outlined),
+                        suffixIcon: IconButton(
+                          icon: Icon(_passwordNotVisible
+                              ? Icons.visibility
+                              : Icons.visibility_off),
+                          onPressed: () {
+                            setState(
+                                  () {
+                                _passwordNotVisible = !_passwordNotVisible;
+                              },
+                            );
+                          },
+                        ),
                         labelText: '密碼',
                       ),
-                      obscureText: true,
+                      obscureText: _passwordNotVisible,
                     ),//密碼
                     SizedBox(height: 20),
                     ElevatedButton(