title: Error: The non-abstract class 'InternalSelectableMathState' is missing implementations for these members - Flutter 2.8.1
body: <p>Here I am upgrading my Flutter 2.5 to 2.8. When I tried to run my previous existing project, I found this error. But in 2.5 it works everything perfectly.</p>
  <p>I am trying this from StackOverflow: <a href="https://stackoverflow.com/questions/70334900/error-the-non-abstract-class-internalselectablemathstate/70335197#70335197">The same issue, But I am couldn't solve by this</a></p>
  <p>I found this error --</p>
  <pre><code>[satota_app] flutter pub get
  Running &quot;flutter pub get&quot; in satota_app...                      
  Because google_maps_place_picker &gt;=2.0.0-nullsafety.0 depends on provider ^5.0.0 and no versions of google_maps_place_picker match &gt;=2.0.0-nullsafety &lt;2.0.0-nullsafety.0, google_maps_place_picker &gt;=2.0.0-nullsafety requires provider ^5.0.0.
  So, because satota_app depends on both provider ^6.0.2 and google_maps_place_picker ^2.0.0-nullsafety, version solving failed.
  pub get failed (1; So, because satota_app depends on both provider ^6.0.2 and google_maps_place_picker ^2.0.0-nullsafety, version solving failed.)
  exit code 1
  </code></pre>
  <p>How can I solve this problem?</p>
  <pre><code>Launching lib\main.dart on vivo 1820 in debug mode...
  lib\main.dart:1
  /C:/Users/ramja/Documents/DartConfig/flutterSDK/flutter/.pub-cache/hosted/pub.dartlang.org/flutter_math_fork-0.3.3+1/lib/src/widgets/selectable.dart:407:7: Error: The non-abstract class 'InternalSelectableMathState' is missing implementations for these members:
   - TextSelectionDelegate.copySelection
   - TextSelectionDelegate.cutSelection
   - TextSelectionDelegate.pasteText
   - TextSelectionDelegate.selectAll
  Try to either
   - provide an implementation,
   - inherit an implementation from a superclass or mixin,
   - mark the class as abstract, or
   - provide a 'noSuchMethod' implementation.
  
  class InternalSelectableMathState extends State&lt;InternalSelectableMath&gt;
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  /C:/Users/ramja/Documents/DartConfig/flutterSDK/flutter/packages/flutter/lib/src/services/text_input.dart:985:8: Context: 'TextSelectionDelegate.copySelection' is defined here.
    void copySelection(SelectionChangedCause cause);
  
         ^^^^^^^^^^^^^
  /C:/Users/ramja/Documents/DartConfig/flutterSDK/flutter/packages/flutter/lib/src/services/text_input.dart:965:8: Context: 'TextSelectionDelegate.cutSelection' is defined here.
    void cutSelection(SelectionChangedCause cause);
         ^^^^^^^^^^^^
  
  /C:/Users/ramja/Documents/DartConfig/flutterSDK/flutter/packages/flutter/lib/src/services/text_input.dart:973:16: Context: 'TextSelectionDelegate.pasteText' is defined here.
    Future&lt;void&gt; pasteText(SelectionChangedCause cause);
                 ^^^^^^^^^
  /C:/Users/ramja/Documents/DartConfig/flutterSDK/flutter/packages/flutter/lib/src/services/text_input.dart:979:8: Context: 'TextSelectionDelegate.selectAll' is defined here.
    void selectAll(SelectionChangedCause cause);
  
         ^^^^^^^^^
  2
  
  FAILURE: Build failed with an exception.
  
  * Where:
  Script 'C:\Users\ramja\Documents\DartConfig\flutterSDK\flutter\packages\flutter_tools\gradle\flutter.gradle' line: 1070
  
  * What went wrong:
  Execution failed for task ':app:compileFlutterBuildDebug'.
  &gt; Process 'command 'C:\Users\ramja\Documents\DartConfig\flutterSDK\flutter\bin\flutter.bat'' finished with non-zero exit value 1
  
  * 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 44s
  Exception: Gradle task assembleDebug failed with exit code 1
  Exited (sigterm)
  </code></pre>
  <p><strong>My Pubspec.yml is :</strong></p>
  <pre><code>name: satota_app
  description: This is the flutter mobile application for satota     
  publish_to: 'none'  
  version: 2.0.0+10
  
  environment:
    sdk: &quot;&gt;=2.7.0 &lt;3.0.0&quot;
  
  dependencies:
    flutter:
      sdk: flutter
    flutter_localizations:
      sdk: flutter
    http:  
    provider: ^5.0.0
    flutter_math_fork: #if I use any version of this package output is status code -1
    json_annotation:  
    logging:  
    connectivity: 
    shimmer:  
    bordered_text:  
    flutter_html:
    flutter_svg:  
    url_launcher: 
    toast:
    shared_preferences:
    flutter_icons:
    dotted_line:
    timeline_list:
    progress_dialog:
    after_init:
    webview_flutter:
    clipboard: 
    google_fonts:
    flutter_rating_bar:
    expandable:
    dropdown_search:
    flutter_countdown_timer:
    splashscreen:
    package_info:
    intl_phone_number_input: 
    flutter_chat_bubble:
   
    cupertino_icons: 
    carousel_slider: 
    cached_network_image: 
    timeline_tile: 
    shared_value: 
    rename: 
    permission_handler: 
    image_picker: 
    flutter_facebook_auth:
    google_sign_in:
    google_maps_place_picker: ^2.0.0-nullsafety 
    firebase_messaging: 
    one_context:
    social_share:
    flutter_typeahead:
    photo_view: 
    intl: 
    
    
  dev_dependencies:
    flutter_test:
      sdk: flutter
    build_runner:
    json_serializable:
    flutter_launcher_icons:
    google_maps_flutter: 
  
  
  flutter_icons:
    android: true
    ios: true
    image_path: &quot;assets/app_logo.png&quot;
   
  flutter:
    uses-material-design: true
    generate: true
    assets:
      - assets/
      - dummy_assets/
  
  
   
  </code></pre>
  <p>thanks.......</p>