Flutter Execution failed for task ':app:processDebugResources'

Question

I left my flutter project for a while when Flutter beta v1.0.0 was out. Now I moved my project to a new system with latest Flutter (stable v1.2.1) and Dart and ran into this build exception problem.

Note this project is working fine on my old desktop flutter doctor output below

Doctor summary (to see all details, run flutter doctor -v):
[✓] Flutter (Channel beta, v1.0.0, on Linux, locale en_GB.UTF-8)
[!] Android toolchain - develop for Android devices (Android SDK 28.0.3)
    ! Some Android licenses not accepted.  To resolve this, run: flutter doctor --android-licenses
[✓] Android Studio (version 3.2)
    ✗ Flutter plugin not installed; this adds Flutter specific functionality.
    ✗ Dart plugin not installed; this adds Dart specific functionality.
[✓] Connected device (1 available)

flutter doctor output of new/current system

Doctor summary (to see all details, run flutter doctor -v):
[√] Flutter (Channel stable, v1.2.1, on Microsoft Windows [Version 10.0.17763.379], locale en-IN)
[√] Android toolchain - develop for Android devices (Android SDK version 28.0.3)
[!] Android Studio (version 3.2)
    X Flutter plugin not installed; this adds Flutter specific functionality.
    X Dart plugin not installed; this adds Dart specific functionality.
[√] VS Code (version 1.32.3)
[√] Connected device (1 available)

pubsec.yaml

gist link to pubsec.yaml

Since I'm coming back after a long time I have no idea what changes Flutter went through can anyone please help me out

Output of flutter run on current system

Launching lib/main.dart on Android SDK built for x86 in debug mode...
Initializing gradle...                                              1.5s
Resolving dependencies...                                           6.0s

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app:processDebugResources'.
> Android resource linking failed
  Output:  D:\Android Projects\maze-flutter\build\app\intermediates\incremental\mergeDebugResources\merged.dir\values-v28\values-v28.xml:7: error: resource android:attr/dialogCornerRadius not found.
  D:\Android Projects\maze-flutter\build\app\intermediates\incremental\mergeDebugResources\merged.dir\values-v28\values-v28.xml:11: error: resource android:attr/dialogCornerRadius not found.
  D:\Android Projects\maze-flutter\build\app\intermediates\incremental\mergeDebugResources\merged.dir\values\values.xml:956: error: resource android:attr/fontVariationSettings not found.
  D:\Android Projects\maze-flutter\build\app\intermediates\incremental\mergeDebugResources\merged.dir\values\values.xml:957: error: resource android:attr/ttcIndex not found.
  error: failed linking references.

  Command: C:\Users\powerpurple\.gradle\caches\transforms-1\files-1.1\aapt2-3.2.1-4818971-windows.jar\18c59619c56cba96590906f3917a302b\aapt2-3.2.1-4818971-windows\aapt2.exe link -I\
          C:\Users\powerpurple\AppData\Local\Android\sdk\platforms\android-27\android.jar\
          --manifest\
          D:\Android Projects\maze-flutter\build\app\intermediates\merged_manifests\debug\processDebugManifest\merged\AndroidManifest.xml\
          -o\
          D:\Android Projects\maze-flutter\build\app\intermediates\processed_res\debug\processDebugResources\out\resources-debug.ap_\
          -R\
          @D:\Android Projects\maze-flutter\build\app\intermediates\incremental\processDebugResources\resources-list-for-resources-debug.ap_.txt\
          --auto-add-overlay\
          --java\
          D:\Android Projects\maze-flutter\build\app\generated\not_namespaced_r_class_sources\debug\processDebugResources\r\
          --custom-package\
          com.example.codee\
          -0\
          apk\
          --output-text-symbols\
          D:\Android Projects\maze-flutter\build\app\intermediates\symbols\debug\R.txt\
          --no-version-vectors
  Daemon:  AAPT2 aapt2-3.2.1-4818971-windows Daemon #0
  Output:  C:\Users\powerpurple\.gradle\caches\transforms-1\files-1.1\appcompat-1.0.0-rc01.aar\353a670f458ae84ffafa8b187ee27491\res\values-v28\values-v28.xml:9:5-12:13: AAPT: error: resource android:attr/dialogCornerRadius not found.

  D:\Android Projects\maze-flutter\build\app\intermediates\incremental\mergeDebugResources\merged.dir\values-v28\values-v28.xml:11: AAPT: error: resource android:attr/dialogCornerRadius not found.

  C:\Users\powerpurple\.gradle\caches\transforms-1\files-1.1\core-1.0.1.aar\f099bdc17ba82cfe6a5a3ab5ab60bee4\res\values\values.xml:89:5-125:25: AAPT: error: resource android:attr/fontVariationSettings not found.

  C:\Users\powerpurple\.gradle\caches\transforms-1\files-1.1\core-1.0.1.aar\f099bdc17ba82cfe6a5a3ab5ab60bee4\res\values\values.xml:89:5-125:25: AAPT: error: resource android:attr/ttcIndex not found.

  error: failed linking references.
  Command: C:\Users\powerpurple\.gradle\caches\transforms-1\files-1.1\aapt2-3.2.1-4818971-windows.jar\18c59619c56cba96590906f3917a302b\aapt2-3.2.1-4818971-windows\aapt2.exe link -I\
          C:\Users\powerpurple\AppData\Local\Android\sdk\platforms\android-27\android.jar\
          --manifest\
          D:\Android Projects\maze-flutter\build\app\intermediates\merged_manifests\debug\processDebugManifest\merged\AndroidManifest.xml\
          -o\
          D:\Android Projects\maze-flutter\build\app\intermediates\processed_res\debug\processDebugResources\out\resources-debug.ap_\
          -R\
          @D:\Android Projects\maze-flutter\build\app\intermediates\incremental\processDebugResources\resources-list-for-resources-debug.ap_.txt\
          --auto-add-overlay\
          --java\
          D:\Android Projects\maze-flutter\build\app\generated\not_namespaced_r_class_sources\debug\processDebugResources\r\
          --custom-package\
          com.example.codee\
          -0\
          apk\
          --output-text-symbols\
          D:\Android Projects\maze-flutter\build\app\intermediates\symbols\debug\R.txt\
PS D:\Android Projects\maze-flutter> flutter run
Using hardware rendering with device Android SDK built for x86. If you get graphics artifacts, consider enabling software rendering with
"--enable-software-rendering".
Launching lib/main.dart on Android SDK built for x86 in debug mode...
Initializing gradle...                                              1.4s
Resolving dependencies...                                           5.7s

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app:processDebugResources'.
> Android resource linking failed
  Output:  D:\Android Projects\maze-flutter\build\app\intermediates\incremental\mergeDebugResources\merged.dir\values-v28\values-v28.xml:7: error: resource android:attr/dialogCornerRadius not found.
  D:\Android Projects\maze-flutter\build\app\intermediates\incremental\mergeDebugResources\merged.dir\values-v28\values-v28.xml:11: error: resource android:attr/dialogCornerRadius not found.  D:\Android Projects\maze-flutter\build\app\intermediates\incremental\mergeDebugResources\merged.dir\values\values.xml:956: error: resource android:attr/fontVariationSettings not found.
  D:\Android Projects\maze-flutter\build\app\intermediates\incremental\mergeDebugResources\merged.dir\values\values.xml:957: error: resource android:attr/ttcIndex not found.
  error: failed linking references.

  Command: C:\Users\powerpurple\.gradle\caches\transforms-1\files-1.1\aapt2-3.2.1-4818971-windows.jar\18c59619c56cba96590906f3917a302b\aapt2-3.2.1-4818971-windows\aapt2.exe link -I\
          C:\Users\powerpurple\AppData\Local\Android\sdk\platforms\android-27\android.jar\
          --manifest\
          D:\Android Projects\maze-flutter\build\app\intermediates\merged_manifests\debug\processDebugManifest\merged\AndroidManifest.xml\
          -o\
          D:\Android Projects\maze-flutter\build\app\intermediates\processed_res\debug\processDebugResources\out\resources-debug.ap_\
          -R\
          @D:\Android Projects\maze-flutter\build\app\intermediates\incremental\processDebugResources\resources-list-for-resources-debug.ap_.txt\
          --auto-add-overlay\
          --java\
          D:\Android Projects\maze-flutter\build\app\generated\not_namespaced_r_class_sources\debug\processDebugResources\r\
          --custom-package\
          com.example.codee\
          -0\
          apk\
          --output-text-symbols\
          D:\Android Projects\maze-flutter\build\app\intermediates\symbols\debug\R.txt\
          --no-version-vectors
  Daemon:  AAPT2 aapt2-3.2.1-4818971-windows Daemon #0
  Output:  C:\Users\powerpurple\.gradle\caches\transforms-1\files-1.1\appcompat-1.0.0-rc01.aar\353a670f458ae84ffafa8b187ee27491\res\values-v28\values-v28.xml:9:5-12:13: AAPT: error: resource android:attr/dialogCornerRadius not found.

  D:\Android Projects\maze-flutter\build\app\intermediates\incremental\mergeDebugResources\merged.dir\values-v28\values-v28.xml:11: AAPT: error: resource android:attr/dialogCornerRadius not found.

  C:\Users\powerpurple\.gradle\caches\transforms-1\files-1.1\core-1.0.1.aar\f099bdc17ba82cfe6a5a3ab5ab60bee4\res\values\values.xml:89:5-125:25: AAPT: error: resource android:attr/fontVariationSettings not found.

  C:\Users\powerpurple\.gradle\caches\transforms-1\files-1.1\core-1.0.1.aar\f099bdc17ba82cfe6a5a3ab5ab60bee4\res\values\values.xml:89:5-125:25: AAPT: error: resource android:attr/ttcIndex not found.

  error: failed linking references.
  Command: C:\Users\powerpurple\.gradle\caches\transforms-1\files-1.1\aapt2-3.2.1-4818971-windows.jar\18c59619c56cba96590906f3917a302b\aapt2-3.2.1-4818971-windows\aapt2.exe link -I\
          C:\Users\powerpurple\AppData\Local\Android\sdk\platforms\android-27\android.jar\
          --manifest\
          D:\Android Projects\maze-flutter\build\app\intermediates\merged_manifests\debug\processDebugManifest\merged\AndroidManifest.xml\
          -o\
          D:\Android Projects\maze-flutter\build\app\intermediates\processed_res\debug\processDebugResources\out\resources-debug.ap_\
          -R\
          @D:\Android Projects\maze-flutter\build\app\intermediates\incremental\processDebugResources\resources-list-for-resources-debug.ap_.txt\
          --auto-add-overlay\
          --java\
          D:\Android Projects\maze-flutter\build\app\generated\not_namespaced_r_class_sources\debug\processDebugResources\r\
          --custom-package\
          com.example.codee\
          -0\
          apk\
          --output-text-symbols\
          D:\Android Projects\maze-flutter\build\app\intermediates\symbols\debug\R.txt\
          --no-version-vectors
  Daemon:  AAPT2 aapt2-3.2.1-4818971-windows Daemon #0

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

* Get more help at https://help.gradle.org

BUILD FAILED in 18s
Running Gradle task 'assembleDebug'...
Running Gradle task 'assembleDebug'... Done                        19.6s
*******************************************************************************************
The Gradle failure may have been because of AndroidX incompatibilities in this Flutter app.
See * for more information on the problem and how to fix it.
*******************************************************************************************
Gradle task assembleDebug failed with exit code 1

Answer 1

The missing resources were only added in API 28. You need to update your compileSDKversion in your build.gradle file to version 28.

Answer 2

compileSdkVersion update worked for me!
/AppName/android/app/build.gradle
adnroid compileSdkVersion: 28 to compileSdkVersion: 30

OS: Ubuntu 20.04 LTS
Android emulator API 30
Dart 2.10.2
Flutter 1.22.2