file connection permission

lib/common.dart

@@ -255,3 +255,54 @@ class AccessibilityListener extends StatelessWidget {
         child: child);
   }
 }
+
+class PermissionManager {
+  static Completer<bool>? _completer;
+  static Timer? _timer;
+  static var _current = "";
+
+  static final permissions = ["audio", "file"];
+
+  static bool isWaitingFile() {
+    if (_completer != null) {
+      return !_completer!.isCompleted && _current == "file";
+    }
+    return false;
+  }
+
+  static Future<bool> check(String type) {
+    if (!permissions.contains(type))
+      return Future.error("Wrong permission!$type");
+    return FFI.invokeMethod("check_permission", type);
+  }
+
+  static Future<bool> request(String type) {
+    if (!permissions.contains(type))
+      return Future.error("Wrong permission!$type");
+
+    _current = type;
+    _completer = Completer<bool>();
+    FFI.invokeMethod("request_permission", type);
+
+    // timeout
+    _timer?.cancel();
+    _timer = Timer(Duration(seconds: 60), () {
+      if (_completer == null) return;
+      if (!_completer!.isCompleted) {
+        _completer!.complete(false);
+      }
+      _completer = null;
+      _current = "";
+    });
+    return _completer!.future;
+  }
+
+  static complete(String type, bool res) {
+    if (type != _current) {
+      res = false;
+    }
+    _timer?.cancel();
+    _completer?.complete(res);
+    _current = "";
+  }
+}

lib/models/server_model.dart

@@ -508,54 +508,3 @@ showInputWarnAlert() {
         ],
       ));
 }
-
-class PermissionManager {
-  static Completer<bool>? _completer;
-  static Timer? _timer;
-  static var _current = "";
-
-  static final permissions = ["audio", "file"];
-
-  static bool isWaitingFile() {
-    if (_completer != null) {
-      return !_completer!.isCompleted && _current == "file";
-    }
-    return false;
-  }
-
-  static Future<bool> check(String type) {
-    if (!permissions.contains(type))
-      return Future.error("Wrong permission!$type");
-    return FFI.invokeMethod("check_permission", type);
-  }
-
-  static Future<bool> request(String type) {
-    if (!permissions.contains(type))
-      return Future.error("Wrong permission!$type");
-
-    _current = type;
-    _completer = Completer<bool>();
-    FFI.invokeMethod("request_permission", type);
-
-    // timeout
-    _timer?.cancel();
-    _timer = Timer(Duration(seconds: 60), () {
-      if (_completer == null) return;
-      if (!_completer!.isCompleted) {
-        _completer!.complete(false);
-      }
-      _completer = null;
-      _current = "";
-    });
-    return _completer!.future;
-  }
-
-  static complete(String type, bool res) {
-    if (type != _current) {
-      res = false;
-    }
-    _timer?.cancel();
-    _completer?.complete(res);
-    _current = "";
-  }
-}

lib/pages/connection_page.dart

@@ -65,10 +65,15 @@ class _ConnectionPageState extends State<ConnectionPage> {
     connect(id);
   }
 
-  void connect(String id, {bool isFileTransfer = false}) {
+  void connect(String id, {bool isFileTransfer = false}) async {
     if (id == '') return;
     id = id.replaceAll(' ', '');
     if (isFileTransfer) {
+      if (!await PermissionManager.check("file")) {
+        if (!await PermissionManager.request("file")) {
+          return;
+        }
+      }
       Navigator.push(
         context,
         MaterialPageRoute(