Flutter Warning: WWindowOnBackDispatcher sendCancelIfRunning - How to Fix? - Stack Overflow

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I am developing a Flutter app, and I keep seeing this warning in my logs when pressing the back button:

W/WindowOnBackDispatcher(5979): sendCancelIfRunning: isInProgress=false callback=io.flutter.embedding.android.FlutterActivity$1@3957dc5

Questions:

• What does this warning mean?
• How can I resolve it or safely ignore it?
• Does this affect my app’s UI performance?

Flutter Version: (Run flutter doctor -v and include the output)
Device/Emulator: (Specify if it happens only on an emulator or real device)
Android Version: (Mention the Android OS version you are testing on)

What I Have Tried

1. Checked WillPopScope implementation:

   WillPopScope(
     onWillPop: () async {
       if (Navigator.of(context).canPop()) {
         Navigator.of(context).pop();
         return false;
       }
       return true;
     },
     child: Scaffold(
       appBar: AppBar(title: Text("Back Handling")),
       body: Center(child: Text("Press Back")),
     ),
   );
   

2. Ran flutter upgrade to ensure I have the latest version.
3. Tried running on both an emulator and a physical device, but the warning still appears.
4. Checked MainActivity.kt, but I am not overriding any back button behavior.

I am developing a Flutter app, and I keep seeing this warning in my logs when pressing the back button:

W/WindowOnBackDispatcher(5979): sendCancelIfRunning: isInProgress=false callback=io.flutter.embedding.android.FlutterActivity$1@3957dc5

Questions:

• What does this warning mean?
• How can I resolve it or safely ignore it?
• Does this affect my app’s UI performance?

Flutter Version: (Run flutter doctor -v and include the output)
Device/Emulator: (Specify if it happens only on an emulator or real device)
Android Version: (Mention the Android OS version you are testing on)

What I Have Tried

1. Checked WillPopScope implementation:

   WillPopScope(
     onWillPop: () async {
       if (Navigator.of(context).canPop()) {
         Navigator.of(context).pop();
         return false;
       }
       return true;
     },
     child: Scaffold(
       appBar: AppBar(title: Text("Back Handling")),
       body: Center(child: Text("Press Back")),
     ),
   );
   

2. Ran flutter upgrade to ensure I have the latest version.
3. Tried running on both an emulator and a physical device, but the warning still appears.
4. Checked MainActivity.kt, but I am not overriding any back button behavior.

• flutter

Share Improve this question Follow asked Mar 30 at 6:57 Sahil ParmarSahil Parmar 1

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1 Answer 1

Sorted by: Reset to default 0

You can safely ignore this warning unless you notice unexpected behavior in back navigation. It does not affect UI performance and is mainly a log message.

If you want a solution, then:

WillPopScope(
  onWillPop: () async {
    if (Navigator.of(context).canPop()) {
      Navigator.of(context).pop();
    } else {
      SystemNavigator.pop(); // You can close the app cleanly
    }
    return false; // Prevents Flutter from processing the back event further
  },
  child: Scaffold(
    appBar: AppBar(title: Text("Back Handling")),
    body: Center(child: Text("Press Back")),
  ),
);

This ensures that when there are no more screens to pop, SystemNavigator.pop() exits the app gracefully, preventing the warning.

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