feat(login): 新增谷歌密码自动填充的隐形原生输入桥

新增 AutofillBridge.java：隐形原生 EditText（低透明度伪可见）设置 autofillHints，支持填充建议与保存提示，commit 采用反射调用规避符号解析问题

新增 AutofillBridge.cs：拦截 InputField 点击改由原生框承接输入，屏幕坐标换算、文本实时同步回显；登录邮箱/密码框接入

登录点击时先 commit 触发保存密码再隐藏；失焦/键盘完成时软隐藏（视图保留树上供快照采集），hide 防重入修复 NPE；proguard-user.txt 添加 keep 规则防 R8 剥离

状态：待真机验证填充与保存提示，已加 autofill 会话诊断日志

Assets/Plugins/Android/AutofillBridge.java

@@ -0,0 +1,323 @@
+package com.photonmatrix.autofill;
+
+import android.app.Activity;
+import android.graphics.Color;
+import android.text.Editable;
+import android.text.InputFilter;
+import android.text.InputType;
+import android.text.TextWatcher;
+import android.view.Gravity;
+import android.view.inputmethod.InputMethodManager;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.EditText;
+import android.widget.FrameLayout;
+import com.unity3d.player.UnityPlayer;
+
+/**
+ * 隐形原生输入桥（Android 谷歌密码自动填充）
+ *
+ * 原理：在 Unity InputField 的屏幕位置上叠加一个视觉隐形（低透明度、无背景）的原生 EditText，
+ * 通过 autofillHints 让谷歌密码管理器识别该输入框，从而提供填充建议和"保存密码"提示。
+ * 输入内容通过 TextWatcher 实时回传给 Unity 侧同步显示。
+ */
+public class AutofillBridge {
+    private static final String TAG = "[AUTOFILL-BRIDGE]";
+    private static final String RECEIVER_GO_NAME = "AutofillBridgeReceiver";
+
+    private static EditText sEditText;
+    private static EditText sCompanionUsername; // 密码页配套的隐形用户名框（用于成对保存账号密码）
+
+    /**
+     * 显示隐形输入桥
+     * @param hint autofillHints 值："emailAddress" / "username" / "password"
+     * @param initialText 初始文本（Unity InputField 当前值）
+     * @param x 屏幕像素坐标（Android 屏幕坐标系，y 从顶部开始）
+     * @param y 同上
+     * @param w 宽（像素）
+     * @param h 高（像素）
+     * @param maxLength 最大字符数（0 表示不限制）
+     * @param companionUsername 密码输入时配套的账号（非空则额外挂一个隐形用户名框，用于成对保存）
+     */
+    public static void show(final String hint, final String initialText,
+                            final int x, final int y, final int w, final int h,
+                            final int maxLength, final String companionUsername) {
+        final Activity activity = UnityPlayer.currentActivity;
+        if (activity == null || activity.isFinishing()) {
+            return;
+        }
+        activity.runOnUiThread(new Runnable() {
+            @Override
+            public void run() {
+                showInternal(activity, hint, initialText, x, y, w, h, maxLength, companionUsername);
+            }
+        });
+    }
+
+    private static void showInternal(Activity activity, String hint, String initialText,
+                                     int x, int y, int w, int h,
+                                     int maxLength, String companionUsername) {
+        try {
+            hideInternal(activity, false);
+
+            final EditText editText = new EditText(activity);
+            editText.setSingleLine(true);
+            editText.setBackground(null); // 去背景，视觉隐形
+            editText.setAlpha(0.08f);     // 低透明度"伪可见"：完全隐藏时 autofill 服务不生效
+            editText.setHint(null);
+            editText.setTextColor(Color.TRANSPARENT);
+            editText.setCursorVisible(false);
+
+            // 输入类型与 autofillHints
+            editText.setImportantForAutofill(View.IMPORTANT_FOR_AUTOFILL_YES);
+            editText.setAutofillHints(hint);
+            if ("password".equals(hint)) {
+                editText.setInputType(InputType.TYPE_CLASS_TEXT | InputType.TYPE_TEXT_VARIATION_PASSWORD);
+                editText.setImeOptions(android.view.inputmethod.EditorInfo.IME_ACTION_DONE);
+            } else if ("emailAddress".equals(hint)) {
+                editText.setInputType(InputType.TYPE_CLASS_TEXT | InputType.TYPE_TEXT_VARIATION_EMAIL_ADDRESS);
+                editText.setImeOptions(android.view.inputmethod.EditorInfo.IME_ACTION_NEXT);
+            } else {
+                editText.setInputType(InputType.TYPE_CLASS_TEXT);
+                editText.setImeOptions(android.view.inputmethod.EditorInfo.IME_ACTION_DONE);
+            }
+
+            if (maxLength > 0) {
+                editText.setFilters(new InputFilter[]{new InputFilter.LengthFilter(maxLength)});
+            }
+
+            if (initialText != null && !initialText.isEmpty()) {
+                editText.setText(initialText);
+                editText.setSelection(initialText.length());
+            }
+
+            // 文本变化实时回传 Unity（含 autofill 填充的值）
+            editText.addTextChangedListener(new TextWatcher() {
+                @Override
+                public void beforeTextChanged(CharSequence s, int start, int count, int after) {
+                }
+
+                @Override
+                public void onTextChanged(CharSequence s, int start, int before, int count) {
+                }
+
+                @Override
+                public void afterTextChanged(Editable s) {
+                    if (sEditText == editText) {
+                        UnityPlayer.UnitySendMessage(RECEIVER_GO_NAME, "OnNativeTextChanged", s.toString());
+                    }
+                }
+            });
+
+            // IME 完成键：软隐藏（保留视图供登录时 commit 快照采集）
+            editText.setOnEditorActionListener(new android.widget.TextView.OnEditorActionListener() {
+                @Override
+                public boolean onEditorAction(android.widget.TextView v, int actionId, android.view.KeyEvent event) {
+                    softHide();
+                    return false;
+                }
+            });
+
+            // 失焦时软隐藏（兜底）；isFocusable 检查防递归
+            editText.setOnFocusChangeListener(new View.OnFocusChangeListener() {
+                @Override
+                public void onFocusChange(View v, boolean hasFocus) {
+                    if (!hasFocus && sEditText == v && v.isFocusable()) {
+                        softHide();
+                    }
+                }
+            });
+
+            // 位置：与 Unity InputField 屏幕矩形重合
+            ViewGroup root = (ViewGroup) activity.getWindow().getDecorView();
+            FrameLayout.LayoutParams lp = new FrameLayout.LayoutParams(
+                    Math.max(w, 1), Math.max(h, 1));
+            lp.gravity = Gravity.TOP | Gravity.START;
+            root.addView(editText, lp);
+            editText.setTranslationX(x);
+            editText.setTranslationY(y);
+            root.requestLayout();
+
+            sEditText = editText;
+
+            // 密码场景：配套一个隐形"用户名"框，让保存的凭据账号密码成对
+            if (companionUsername != null && !companionUsername.isEmpty()) {
+                EditText companion = new EditText(activity);
+                companion.setSingleLine(true);
+                companion.setBackground(null);
+                companion.setAlpha(0.03f);
+                companion.setTextColor(Color.TRANSPARENT);
+                companion.setCursorVisible(false);
+                companion.setImportantForAutofill(View.IMPORTANT_FOR_AUTOFILL_YES);
+                companion.setAutofillHints(View.AUTOFILL_HINT_USERNAME);
+                companion.setInputType(InputType.TYPE_CLASS_TEXT | InputType.TYPE_TEXT_VARIATION_EMAIL_ADDRESS);
+                companion.setText(companionUsername);
+                companion.setFocusable(false); // 不参与焦点/填充请求，仅参与保存快照
+                companion.setClickable(false);
+                ViewGroup.LayoutParams clp = new FrameLayout.LayoutParams(Math.max(w, 1), Math.max(h, 1));
+                root.addView(companion, clp);
+                companion.setTranslationX(x);
+                companion.setTranslationY(y);
+                sCompanionUsername = companion;
+            }
+
+            // 请求焦点并弹出软键盘
+            editText.setFocusableInTouchMode(true);
+            editText.requestFocus();
+            InputMethodManager imm = (InputMethodManager) activity.getSystemService(Activity.INPUT_METHOD_SERVICE);
+            if (imm != null) {
+                editText.postDelayed(new Runnable() {
+                    @Override
+                    public void run() {
+                        if (sEditText == editText) {
+                            imm.showSoftInput(editText, InputMethodManager.SHOW_IMPLICIT);
+                        }
+                    }
+                }, 100);
+            }
+
+            // autofill 会话诊断：确认系统是否建立了填充会话（1.5 秒后打印状态）
+            editText.postDelayed(new Runnable() {
+                @Override
+                public void run() {
+                    try {
+                        if (sEditText != editText) return;
+                        java.lang.reflect.Method getter = activity.getClass().getMethod("getAutofillManager");
+                        Object afm = getter.invoke(activity);
+                        if (afm != null) {
+                            Object enabled = afm.getClass().getMethod("isEnabled").invoke(afm);
+                            Object filled = afm.getClass().getMethod("hasFilledSession").invoke(afm);
+                            android.util.Log.d(TAG, "autofill 诊断: enabled=" + enabled
+                                    + ", hasFilledSession(会话已建立)=" + filled
+                                    + ", viewFocused=" + editText.isFocused()
+                                    + ", viewShown=" + editText.isShown()
+                                    + ", hints=" + java.util.Arrays.toString(editText.getAutofillHints()));
+                        } else {
+                            android.util.Log.d(TAG, "autofill 诊断: getAutofillManager() 为 null");
+                        }
+                    } catch (Throwable t) {
+                        android.util.Log.e(TAG, "autofill 诊断失败", t);
+                    }
+                }
+            }, 1500);
+        } catch (Throwable t) {
+            android.util.Log.e(TAG, "show failed", t);
+        }
+    }
+
+    /**
+     * 隐藏输入桥
+     * @param commitToAutofill 隐藏前是否触发 autofill 保存
+     */
+    public static void hide(final boolean commitToAutofill) {
+        final Activity activity = UnityPlayer.currentActivity;
+        if (activity == null) {
+            return;
+        }
+        activity.runOnUiThread(new Runnable() {
+            @Override
+            public void run() {
+                hideInternal(activity, commitToAutofill);
+            }
+        });
+    }
+
+    private static void hideInternal(Activity activity, boolean commitToAutofill) {
+        try {
+            // commit 必须在移除视图之前：保存快照采集需要输入框仍在视图树中
+            if (commitToAutofill) {
+                commitInternal(activity);
+            }
+            // 先置空引用再移除，防止移除过程中触发的失焦回调重入 hide 导致 NPE
+            EditText editText = sEditText;
+            EditText companion = sCompanionUsername;
+            sEditText = null;
+            sCompanionUsername = null;
+
+            InputMethodManager imm = (InputMethodManager) activity.getSystemService(Activity.INPUT_METHOD_SERVICE);
+            View focus = activity.getCurrentFocus();
+            if (imm != null && focus != null) {
+                imm.hideSoftInputFromWindow(focus.getWindowToken(), 0);
+            }
+            ViewGroup root = (ViewGroup) activity.getWindow().getDecorView();
+            if (editText != null) {
+                root.removeView(editText);
+            }
+            if (companion != null) {
+                root.removeView(companion);
+            }
+        } catch (Throwable t) {
+            android.util.Log.e(TAG, "hide failed", t);
+        }
+    }
+
+    /**
+     * 软隐藏：收起键盘并解除交互（不可聚焦/不可点击，点击穿透回 Unity），
+     * 但视图保留在视图树上——登录 commit 时 autofill 保存快照仍能采集到输入字段
+     */
+    public static void softHide() {
+        final Activity activity = UnityPlayer.currentActivity;
+        if (activity == null) {
+            return;
+        }
+        activity.runOnUiThread(new Runnable() {
+            @Override
+            public void run() {
+                softHideInternal(activity);
+            }
+        });
+    }
+
+    private static void softHideInternal(Activity activity) {
+        try {
+            EditText editText = sEditText;
+            if (editText == null) {
+                return;
+            }
+            InputMethodManager imm = (InputMethodManager) activity.getSystemService(Activity.INPUT_METHOD_SERVICE);
+            if (imm != null) {
+                imm.hideSoftInputFromWindow(editText.getWindowToken(), 0);
+            }
+            editText.setFocusable(false);
+            editText.setFocusableInTouchMode(false);
+            editText.setClickable(false);
+            editText.setLongClickable(false);
+            editText.clearFocus();
+        } catch (Throwable t) {
+            android.util.Log.e(TAG, "soft hide failed", t);
+        }
+    }
+
+    /**
+     * 触发 autofill 保存流程（登录成功时调用，弹出"保存密码"提示）
+     * 注意：需在输入桥仍挂载在视图树时调用，登录点击时先 commit 再 hide
+     */
+    public static void commit() {
+        final Activity activity = UnityPlayer.currentActivity;
+        if (activity == null) {
+            return;
+        }
+        activity.runOnUiThread(new Runnable() {
+            @Override
+            public void run() {
+                commitInternal(activity);
+            }
+        });
+    }
+
+    private static void commitInternal(Activity activity) {
+        try {
+            if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.O) {
+                // 反射调用 getAutofillManager().commit()，避免部分 android.jar 变体缺少该符号导致编译失败
+                java.lang.reflect.Method getter = activity.getClass().getMethod("getAutofillManager");
+                final Object afm = getter.invoke(activity);
+                if (afm != null) {
+                    java.lang.reflect.Method commit = afm.getClass().getMethod("commit");
+                    commit.invoke(afm);
+                }
+            }
+        } catch (Throwable t) {
+            android.util.Log.e(TAG, "commit failed", t);
+        }
+    }
+}

Assets/Plugins/Android/AutofillBridge.java.meta

@@ -0,0 +1,32 @@
+fileFormatVersion: 2
+guid: 981a182736820804d8310023dc57abc7
+PluginImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  iconMap: {}
+  executionOrder: {}
+  defineConstraints: []
+  isPreloaded: 0
+  isOverridable: 0
+  isExplicitlyReferenced: 0
+  validateReferences: 1
+  platformData:
+  - first:
+      Android: Android
+    second:
+      enabled: 1
+      settings: {}
+  - first:
+      Any: 
+    second:
+      enabled: 0
+      settings: {}
+  - first:
+      Editor: Editor
+    second:
+      enabled: 0
+      settings:
+        DefaultValueInitialized: true
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

Assets/Plugins/Android/proguard-user.txt

@@ -4,6 +4,9 @@
 # 保留 FilePicker 插件类（通过 AndroidJavaClass 反射调用，R8 无法检测到使用）
 -keep class com.unity.filepicker.** { *; }
 
+# 保留谷歌自动填充隐形输入桥（通过 AndroidJavaClass 反射调用，R8 无法检测到使用）
+-keep class com.photonmatrix.autofill.** { *; }
+
 # 保留 ffmpeg-kit 全部类(R8 混淆后 ffmpeg-kit 内部 native 调用会失效)
 -keep class com.arthenica.ffmpegkit.** { *; }
 -keep class com.arthenica.ffmpegkit.**$* { *; }

Assets/Scripts/UI/Components/AutofillBridge.cs

@@ -0,0 +1,184 @@
+using UnityEngine;
+using UnityEngine.UI;
+
+namespace Kill.UI.Components
+{
+    /// <summary>
+    /// autofill 语义类型（对应 Android autofillHints）
+    /// </summary>
+    public enum AutofillHint
+    {
+        EmailAddress,   // emailAddress
+        Username,       // username
+        Password,       // password
+    }
+
+    /// <summary>
+    /// 隐形原生输入桥（Android 谷歌密码自动填充）
+    ///
+    /// 用法：AutofillBridge.Attach(inputField, AutofillHint.Password)
+    /// Attach 后会在 InputField 上叠一层透明按钮拦截点击：点击不再激活 Unity 自带键盘，
+    /// 而是在 InputField 的屏幕位置弹出带 autofillHints 的隐形原生 EditText，
+    /// 由谷歌密码管理器提供填充建议；输入内容实时同步回 Unity InputField 显示。
+    /// 登录成功时调用 Commit() 触发"保存密码"提示。
+    /// </summary>
+    public static class AutofillBridge
+    {
+        private const string JavaClass = "com.photonmatrix.autofill.AutofillBridge";
+        private const string ReceiverGoName = "AutofillBridgeReceiver";
+
+        private static AndroidJavaClass sJava;
+        private static GameObject sReceiverGo;
+        private static InputField sActiveField;
+
+        /// <summary>密码页配套的账号（保存凭据时账号密码成对）</summary>
+        public static string CompanionUsername { get; set; } = "";
+
+        public static bool Supported =>
+            !Application.isEditor && Application.platform == RuntimePlatform.Android;
+
+        /// <summary>
+        /// 绑定 InputField：叠加透明按钮拦截点击，改由原生输入桥承接
+        /// </summary>
+        public static void Attach(InputField field, AutofillHint hint)
+        {
+            if (field == null || !Supported) return;
+            EnsureReceiver();
+
+            var blockerGo = new GameObject(field.name + "_AutofillBlocker", typeof(RectTransform), typeof(Image), typeof(Button));
+            var blockerRt = blockerGo.GetComponent<RectTransform>();
+            var fieldRt = field.transform as RectTransform;
+            blockerRt.SetParent(fieldRt.parent, false);
+            // 复制 InputField 的布局，完全重合
+            blockerRt.anchorMin = fieldRt.anchorMin;
+            blockerRt.anchorMax = fieldRt.anchorMax;
+            blockerRt.pivot = fieldRt.pivot;
+            blockerRt.anchoredPosition = fieldRt.anchoredPosition;
+            blockerRt.sizeDelta = fieldRt.sizeDelta;
+            blockerRt.localScale = Vector3.one;
+            blockerRt.SetAsLastSibling(); // 保持在 InputField 之上，优先接收点击
+
+            var img = blockerGo.GetComponent<Image>();
+            img.color = new Color(0, 0, 0, 0); // 全透明，仅用于接收射线
+
+            var btn = blockerGo.GetComponent<Button>();
+            btn.transition = Selectable.Transition.None;
+            btn.onClick.AddListener(() => Show(field, hint));
+        }
+
+        /// <summary>
+        /// 显示隐形原生输入框（一般由 Attach 的拦截按钮触发）
+        /// </summary>
+        public static void Show(InputField field, AutofillHint hint)
+        {
+            if (field == null || !Supported) return;
+            EnsureReceiver();
+
+            GetScreenRect(field, out int x, out int y, out int w, out int h);
+            sActiveField = field;
+
+            GetJava().CallStatic("show",
+                ToHintString(hint),
+                field.text ?? "",
+                x, y, w, h,
+                field.characterLimit,
+                CompanionUsername ?? "");
+        }
+
+        /// <summary>隐藏输入桥（切换页面时调用）</summary>
+        public static void Hide()
+        {
+            if (!Supported) return;
+            sActiveField = null;
+            GetJava().CallStatic("hide", false);
+        }
+
+        /// <summary>
+        /// 触发 autofill 保存流程（弹出"保存密码"提示）
+        /// 登录点击时调用：先 Commit 再 Hide
+        /// </summary>
+        public static void Commit()
+        {
+            if (!Supported) return;
+            GetJava().CallStatic("commit");
+        }
+
+        /// <summary>提交并隐藏（登录按钮常用组合）</summary>
+        public static void CommitAndHide()
+        {
+            if (!Supported) return;
+            sActiveField = null;
+            GetJava().CallStatic("hide", true);
+        }
+
+        /// <summary>原生文本变化回调（Java 端 UnitySendMessage 进入）</summary>
+        internal static void DispatchNativeText(string text)
+        {
+            if (sActiveField != null)
+                sActiveField.text = text;
+        }
+
+        private static AndroidJavaClass GetJava()
+        {
+            if (sJava == null)
+                sJava = new AndroidJavaClass(JavaClass);
+            return sJava;
+        }
+
+        private static void EnsureReceiver()
+        {
+            if (sReceiverGo != null) return;
+            var existing = GameObject.Find(ReceiverGoName);
+            sReceiverGo = existing != null ? existing : new GameObject(ReceiverGoName);
+            if (existing == null)
+                sReceiverGo.AddComponent<AutofillBridgeReceiver>();
+        }
+
+        /// <summary>
+        /// InputField 的屏幕像素矩形，并转换为 Android 坐标系（原点左上、y 向下）
+        /// </summary>
+        private static void GetScreenRect(InputField field, out int x, out int y, out int w, out int h)
+        {
+            var rt = field.transform as RectTransform;
+            var canvas = field.GetComponentInParent<Canvas>();
+
+            Camera cam = null;
+            if (canvas != null && canvas.renderMode != RenderMode.ScreenSpaceOverlay)
+                cam = canvas.worldCamera;
+
+            var corners = new Vector3[4];
+            rt.GetWorldCorners(corners); // [0]左下 [2]右上
+            Vector2 p0 = RectTransformUtility.WorldToScreenPoint(cam, corners[0]);
+            Vector2 p2 = RectTransformUtility.WorldToScreenPoint(cam, corners[2]);
+
+            int minX = Mathf.RoundToInt(Mathf.Min(p0.x, p2.x));
+            int maxX = Mathf.RoundToInt(Mathf.Max(p0.x, p2.x));
+            int minY = Mathf.RoundToInt(Mathf.Min(p0.y, p2.y));
+            int maxY = Mathf.RoundToInt(Mathf.Max(p0.y, p2.y));
+
+            x = minX;
+            w = maxX - minX;
+            h = maxY - minY;
+            // Unity y 向上 → Android y 向下
+            y = Screen.height - maxY;
+        }
+
+        private static string ToHintString(AutofillHint hint)
+        {
+            switch (hint)
+            {
+                case AutofillHint.Password: return "password";
+                case AutofillHint.Username: return "username";
+                default: return "emailAddress";
+            }
+        }
+    }
+
+    /// <summary>
+    /// Java 端 UnitySendMessage 的接收者（GameObject 名固定为 AutofillBridgeReceiver）
+    /// </summary>
+    public class AutofillBridgeReceiver : MonoBehaviour
+    {
+        public void OnNativeTextChanged(string text) => AutofillBridge.DispatchNativeText(text);
+    }
+}

Assets/Scripts/UI/Components/AutofillBridge.cs.meta

@@ -0,0 +1,11 @@
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+guid: 811b32b915cfad14ab42718829acd9c4
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

Assets/Scripts/UI/Pages/Login/SubPages/LoginPanel.cs

@@ -27,6 +27,9 @@ namespace Kill.UI.Pages
         public Button privacyLinkBtn;
         protected override void OnInitialize()
         {
+            // 谷歌密码自动填充：邮箱框改由隐形原生输入桥承接
+            AutofillBridge.Attach(emailInput, AutofillHint.EmailAddress);
+
             // 绑定按钮事件
             if (loginBtn != null)
                 loginBtn.onClick.AddListener(OnLoginClick);
@@ -64,6 +67,9 @@ namespace Kill.UI.Pages
             privacyToggle.isOn = true;
             errorText.text = "";
             emailInput.text = "";
+
+            // 切回本页时收掉其他页面的原生输入桥
+            AutofillBridge.Hide();
         }
 
         private async void OnLoginClick()

Assets/Scripts/UI/Pages/Login/SubPages/LoginPasswordPanel.cs

@@ -18,6 +18,9 @@ namespace Kill.UI.Pages
 
         protected override void OnInitialize()
         {
+            // 谷歌密码自动填充：密码框改由隐形原生输入桥承接
+            AutofillBridge.Attach(passwordInput, AutofillHint.Password);
+
             if (loginBtn != null)
                 loginBtn.onClick.AddListener(OnLoginClick);
 
@@ -35,6 +38,10 @@ namespace Kill.UI.Pages
                 passwordInput.text = "";
             if (errorText != null)
                 errorText.text = "";
+
+            // 配套账号用于保存凭据时账号密码成对
+            AutofillBridge.CompanionUsername = LoginPageCtrl.Instance.GetCurrentEmail();
+            AutofillBridge.Hide();
         }
 
         private void OnLoginClick()
@@ -46,6 +53,9 @@ namespace Kill.UI.Pages
                 return;
             }
 
+            // 触发谷歌密码管理器的"保存密码"提示（需在输入桥隐藏前调用）
+            AutofillBridge.CommitAndHide();
+
             string email = LoginPageCtrl.Instance.GetCurrentEmail();
 
             // 使用自定义错误版本，在输入框下方显示错误