fix keyboard_listener escape loop

packages/flet/lib/src/controls/keyboard_listener.dart

@@ -1,3 +1,4 @@
+
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
 
@@ -19,6 +20,8 @@ class KeyboardListenerControl extends StatefulWidget {
 
 class _KeyboardListenerControlState extends State<KeyboardListenerControl> {
   final FocusNode _focusNode = FocusNode();
+  bool _escapeDownSent = false;
+  DateTime? _lastSynthesizedEscapeUpAt;
 
   @override
   void initState() {
@@ -43,6 +46,75 @@ class _KeyboardListenerControlState extends State<KeyboardListenerControl> {
     }
   }
 
+  void _triggerKeyEvent(String eventName, KeyEvent keyEvent) {
+    if (keyEvent.logicalKey == LogicalKeyboardKey.escape) {
+      _escapeDownSent = eventName == "key_down";
+    }
+    widget.control
+        .triggerEvent(eventName, {"key": keyEvent.logicalKey.keyLabel});
+  }
+
+  void _triggerEscapeKeyUp() {
+    if (!_escapeDownSent) {
+      return;
+    }
+    _escapeDownSent = false;
+    widget.control.triggerEvent("key_up", {"key": "Escape"});
+  }
+
+  KeyEventResult _handleEscapeLoop(KeyEvent keyEvent) {
+    final isEscape = keyEvent.logicalKey == LogicalKeyboardKey.escape;
+    final isPhysicalEscape =
+        isEscape && keyEvent.physicalKey == PhysicalKeyboardKey.escape;
+    final isPeriodEscape =
+        isEscape && keyEvent.physicalKey == PhysicalKeyboardKey.period;
+    final isMetaUp = keyEvent is KeyUpEvent &&
+        (keyEvent.physicalKey == PhysicalKeyboardKey.metaLeft ||
+            keyEvent.physicalKey == PhysicalKeyboardKey.metaRight ||
+            keyEvent.logicalKey == LogicalKeyboardKey.meta ||
+            keyEvent.logicalKey == LogicalKeyboardKey.metaLeft ||
+            keyEvent.logicalKey == LogicalKeyboardKey.metaRight);
+
+    if (keyEvent is KeyDownEvent &&
+        isPeriodEscape &&
+        HardwareKeyboard.instance.isMetaPressed) {
+      _triggerKeyEvent("key_down", keyEvent);
+      return KeyEventResult.handled;
+    }
+
+    if (keyEvent is KeyUpEvent && isPeriodEscape) {
+      _triggerEscapeKeyUp();
+      return KeyEventResult.handled;
+    }
+
+    if (_escapeDownSent && isMetaUp) {
+      _triggerEscapeKeyUp();
+    }
+
+    if (keyEvent is KeyUpEvent && isPhysicalEscape) {
+      _lastSynthesizedEscapeUpAt = DateTime.now();
+      if (keyEvent.synthesized) {
+        _triggerEscapeKeyUp();
+        return KeyEventResult.handled;
+      }
+    }
+
+    if (keyEvent is KeyDownEvent && isPhysicalEscape) {
+      final lastUpAt = _lastSynthesizedEscapeUpAt;
+      if (lastUpAt != null &&
+          DateTime.now().difference(lastUpAt) <
+              const Duration(milliseconds: 300)) {
+        return KeyEventResult.handled;
+      }
+    }
+
+    if (!isEscape) {
+      _lastSynthesizedEscapeUpAt = null;
+    }
+
+    return KeyEventResult.ignored;
+  }
+
   @override
   Widget build(BuildContext context) {
     debugPrint("KeyboardListener build: ${widget.control.id}");
@@ -53,23 +125,26 @@ class _KeyboardListenerControlState extends State<KeyboardListenerControl> {
       return const ErrorControl("KeyboardListener control has no content.");
     }
 
-    return KeyboardListener(
+    return Focus(
       focusNode: _focusNode,
       autofocus: widget.control.getBool("autofocus", false)!,
       includeSemantics: widget.control.getBool("include_semantics", true)!,
-      onKeyEvent: (keyEvent) {
+      onKeyEvent: (FocusNode node, KeyEvent keyEvent) {
+        final result = _handleEscapeLoop(keyEvent);
+        if (result == KeyEventResult.handled) {
+          return result;
+        }
         if (keyEvent is KeyDownEvent) {
-          widget.control
-              .triggerEvent("key_down", {"key": keyEvent.logicalKey.keyLabel});
+          _triggerKeyEvent("key_down", keyEvent);
         } else if (keyEvent is KeyUpEvent) {
-          widget.control
-              .triggerEvent("key_up", {"key": keyEvent.logicalKey.keyLabel});
+          _triggerKeyEvent("key_up", keyEvent);
         } else if (keyEvent is KeyRepeatEvent) {
-          widget.control.triggerEvent(
-              "key_repeat", {"key": keyEvent.logicalKey.keyLabel});
+          _triggerKeyEvent("key_repeat", keyEvent);
         }
+        return KeyEventResult.ignored;
       },
       child: content,
     );
   }
 }
+