LongPressDraggable does not display feedback in a consistent way

[stephane-archer]

Steps to reproduce

I'm no Mac OS Desktop
I use a LongPressDraggable, this widget has as a child a main image, and for feedback, this widget has an image with a fixed width to make it appear smaller under the cursor.
Depending on where I press the image, the feedback appears in different places, sometimes not even under the cursor.

Expected results

I expect the feedback widget to always appear at the same place each time I do a long press on my image.

Actual results

Code sample

Code sample

LongPressDraggable<String>(
        delay: const Duration(milliseconds: 250),
        ignoringFeedbackPointer: false,
        data: lutPreviewResult.pathLut,
        feedback: MouseRegion(
          cursor: SystemMouseCursors.grabbing,
          child: Image(
              width: 100, image: FileImage(File(lutPreviewResult.pathOutput))),
        ),
        child: LutPreviewWidget(
          pathLut: lutPreviewResult.pathLut,
          pathOutput: lutPreviewResult.pathOutput,
        ),
      )

Screenshots or Video

Screenshots / Video demonstration

[Upload media here]

Logs

Logs

[Paste your logs here]

Flutter Doctor output

Doctor output

[✓] Flutter (Channel stable, 3.19.5, on macOS 13.4.1 22F770820d darwin-x64, locale en-GB)
    • Flutter version 3.19.5 on channel stable at /Users/fractale/flutter
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision 300451adae (3 weeks ago), 2024-03-27 21:54:07 -0500
    • Engine revision e76c956498
    • Dart version 3.3.3
    • DevTools version 2.31.1

[!] Android toolchain - develop for Android devices (Android SDK version 34.0.0)
    • Android SDK at /Users/fractale/Library/Android/sdk
    ✗ cmdline-tools component is missing
      Run `path/to/sdkmanager --install "cmdline-tools;latest"`
      See https://developer.android.com/studio/command-line for more details.
    ✗ Android license status unknown.
      Run `flutter doctor --android-licenses` to accept the SDK licenses.
      See https://flutter.dev/docs/get-started/install/macos#android-setup for more details.

[✓] Xcode - develop for iOS and macOS (Xcode 14.3.1)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Build 14E300c
    • CocoaPods version 1.15.2

[✓] Chrome - develop for the web
    • Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

[✓] Android Studio (version 2022.2)
    • Android Studio at /Applications/Android Studio.app/Contents
    • Flutter plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/9212-flutter
    • Dart plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/6351-dart
    • Java version OpenJDK Runtime Environment (build 17.0.6+0-17.0.6b802.4-9586694)

[✓] VS Code (version 1.88.1)
    • VS Code at /Applications/Visual Studio Code.app/Contents
    • Flutter extension version 3.86.0

[✓] Connected device (2 available)
    • macOS (desktop) • macos  • darwin-x64     • macOS 13.4.1 22F770820d darwin-x64
    • Chrome (web)    • chrome • web-javascript • Google Chrome 124.0.6367.61

[✓] Network resources
    • All expected network resources are available.

[darshankawar]

Thanks for the report @stephane-archer
Can you provide us complete runnable code sample (ex: main.dart) that we can directly run to verify this further ?

[stephane-archer]

import 'dart:io';

import 'package:flutter/gestures.dart';
import 'package:flutter/material.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple),
        useMaterial3: true,
      ),
      home: const MyHomePage(),
    );
  }
}

class MyHomePage extends StatelessWidget {
  const MyHomePage({super.key});

  @override
  Widget build(BuildContext context) {
    return const Scaffold(
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            SizedBox(
              height: 200,
              child: _MyStrangeWidgetBehavior(
                  '/Users/fractale/test_for_flutter/assets/testHorizontal.tiff'),
            ),
          ],
        ),
      ),
    );
  }
}

class _LutPreviewWidget extends StatelessWidget {
  final String _pathOutput;
  const _LutPreviewWidget({required String pathOutput})
      : _pathOutput = pathOutput;

  @override
  Widget build(BuildContext context) {
    return LayoutBuilder(builder: (context, constraints) {
      return FadeInImage(
        image: ResizeImage(
          FileImage(
            File(_pathOutput),
          ),
          width:
              (constraints.maxWidth * MediaQuery.of(context).devicePixelRatio)
                  .toInt(),
        ),
        placeholder: const AssetImage("assets/imgs/Spinner.gif"),
      );
    });
  }
}

class _MyStrangeWidgetBehavior extends StatelessWidget {
  final String lutPreviewResult;
  const _MyStrangeWidgetBehavior(this.lutPreviewResult);

  @override
  Widget build(BuildContext context) {
    return MouseRegion(
      cursor: SystemMouseCursors.grab,
      child: LongPressDraggable<String>(
        delay: kLongPressTimeout ~/ 2,
        ignoringFeedbackPointer: true,
        data: lutPreviewResult,
        feedback: MouseRegion(
          cursor: SystemMouseCursors.grabbing,
          child: Image(width: 100, image: FileImage(File(lutPreviewResult))),
        ),
        child: _LutPreviewWidget(
          pathOutput: lutPreviewResult,
        ),
      ),
    );
  }
}

[stephane-archer]

the Spinner:

the main image is a tiff: 3840 × 2160 (large file)

[stephane-archer]

Demo:

[stephane-archer]

MacOs

Flutter 3.19.6 • channel stable • https://github.com/flutter/flutter.git
Framework • revision 54e66469a9 (2 days ago) • 2024-04-17 13:08:03 -0700
Engine • revision c4cd48e186
Tools • Dart 3.3.4 • DevTools 2.31.1

[darshankawar]

Thanks for the update. I was able to replicate the reported behavior running on macos desktop.

stable, master flutter doctor -v

[!] Flutter (Channel stable, 3.19.5, on macOS 12.2.1 21D62 darwin-x64, locale
    en-GB)
    • Flutter version 3.19.5 on channel stable at
      /Users/dhs/documents/fluttersdk/flutter
    ! Warning: `flutter` on your path resolves to
      /Users/dhs/Documents/Fluttersdk/flutter/bin/flutter, which is not inside
      your current Flutter SDK checkout at
      /Users/dhs/documents/fluttersdk/flutter. Consider adding
      /Users/dhs/documents/fluttersdk/flutter/bin to the front of your path.
    ! Warning: `dart` on your path resolves to
      /Users/dhs/Documents/Fluttersdk/flutter/bin/dart, which is not inside your
      current Flutter SDK checkout at /Users/dhs/documents/fluttersdk/flutter.
      Consider adding /Users/dhs/documents/fluttersdk/flutter/bin to the front
      of your path.
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision 300451adae (4 days ago), 2024-03-27 21:54:07 -0500
    • Engine revision e76c956498
    • Dart version 3.3.3
    • DevTools version 2.31.1
    • If those were intentional, you can disregard the above warnings; however
      it is recommended to use "git" directly to perform update checks and
      upgrades.

[!] Xcode - develop for iOS and macOS (Xcode 12.3)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    ! Flutter recommends a minimum Xcode version of 13.
      Download the latest version or update via the Mac App Store.
    • CocoaPods version 1.11.2

[✓] Chrome - develop for the web
    • Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

[✓] VS Code (version 1.62.0)
    • VS Code at /Applications/Visual Studio Code.app/Contents
    • Flutter extension version 3.21.0

[✓] Connected device (5 available)
    • SM G975F (mobile)       • RZ8M802WY0X • android-arm64   • Android 11 (API 30)
    • Darshan's iphone (mobile)  • 21150b119064aecc249dfcfe05e259197461ce23 •
      ios            • iOS 14.4.1 18D61
    • iPhone 12 Pro Max (mobile) • A5473606-0213-4FD8-BA16-553433949729     •
      ios            • com.apple.CoreSimulator.SimRuntime.iOS-14-3 (simulator)
    • macOS (desktop)            • macos                                    •
      darwin-x64     • Mac OS X 10.15.4 19E2269 darwin-x64
    • Chrome (web)               • chrome                                   •
      web-javascript • Google Chrome 98.0.4758.80

[✓] HTTP Host Availability
    • All required HTTP hosts are available

! Doctor found issues in 1 category.

[!] Flutter (Channel master, 3.22.0-14.0.pre.32, on macOS 12.2.1 21D62
    darwin-x64, locale en-GB)
    • Flutter version 3.22.0-14.0.pre.32 on channel master at
      /Users/dhs/documents/fluttersdk/flutter
    ! Warning: `flutter` on your path resolves to
      /Users/dhs/Documents/Fluttersdk/flutter/bin/flutter, which is not inside
      your current Flutter SDK checkout at
      /Users/dhs/documents/fluttersdk/flutter. Consider adding
      /Users/dhs/documents/fluttersdk/flutter/bin to the front of your path.
    ! Warning: `dart` on your path resolves to
      /Users/dhs/Documents/Fluttersdk/flutter/bin/dart, which is not inside your
      current Flutter SDK checkout at /Users/dhs/documents/fluttersdk/flutter.
      Consider adding /Users/dhs/documents/fluttersdk/flutter/bin to the front
      of your path.
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision d4b42780ba (2 hours ago), 2024-04-19 00:21:25 -0400
    • Engine revision b6234dd198
    • Dart version 3.5.0 (build 3.5.0-76.0.dev)
    • DevTools version 2.35.0-dev.8
    • If those were intentional, you can disregard the above warnings; however
      it is recommended to use "git" directly to perform update checks and
      upgrades.

[!] Android toolchain - develop for Android devices (Android SDK version 30.0.3)
    • Android SDK at /Users/dhs/Library/Android/sdk
    ✗ cmdline-tools component is missing
      Run `path/to/sdkmanager --install "cmdline-tools;latest"`
      See https://developer.android.com/studio/command-line for more details.
    ✗ Android license status unknown.
      Run `flutter doctor --android-licenses` to accept the SDK licenses.
      See https://flutter.dev/docs/get-started/install/macos#android-setup for
      more details.

[✓] Xcode - develop for iOS and macOS (Xcode 13.2.1)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Build 13C100
    • CocoaPods version 1.11.2

[✓] Chrome - develop for the web
    • Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

[✓] IntelliJ IDEA Ultimate Edition (version 2021.3.2)
    • IntelliJ at /Applications/IntelliJ IDEA.app
    • Flutter plugin version 65.1.4
    • Dart plugin version 213.7228

[✓] VS Code (version 1.62.0)
    • VS Code at /Applications/Visual Studio Code.app/Contents
    • Flutter extension version 3.29.0

[✓] Connected device (3 available)
    • Darshan's iphone (mobile) • 21150b119064aecc249dfcfe05e259197461ce23 • ios
      • iOS 15.3.1 19D52
    • macOS (desktop)           • macos                                    •
      darwin-x64     • macOS 12.2.1 21D62 darwin-x64
    • Chrome (web)              • chrome                                   •
      web-javascript • Google Chrome 109.0.5414.119

[✓] Network resources
    • All expected network resources are available.

! Doctor found issues in 1 category.
      
[!] Xcode - develop for iOS and macOS (Xcode 12.3)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    ! Flutter recommends a minimum Xcode version of 13.
      Download the latest version or update via the Mac App Store.
    • CocoaPods version 1.11.2

[✓] Chrome - develop for the web
    • Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

[✓] VS Code (version 1.62.0)
    • VS Code at /Applications/Visual Studio Code.app/Contents
    • Flutter extension version 3.21.0

[✓] Connected device (5 available)
    • SM G975F (mobile)       • RZ8M802WY0X • android-arm64   • Android 11 (API 30)
    • Darshan's iphone (mobile)  • 21150b119064aecc249dfcfe05e259197461ce23 •
      ios            • iOS 14.4.1 18D61
    • iPhone 12 Pro Max (mobile) • A5473606-0213-4FD8-BA16-553433949729     •
      ios            • com.apple.CoreSimulator.SimRuntime.iOS-14-3 (simulator)
    • macOS (desktop)            • macos                                    •
      darwin-x64     • Mac OS X 10.15.4 19E2269 darwin-x64
    • Chrome (web)               • chrome                                   •
      web-javascript • Google Chrome 98.0.4758.80

[✓] HTTP Host Availability
    • All required HTTP hosts are available

! Doctor found issues in 1 category.