Custom Actions Errors

Prerequisites

• A basic understanding of how custom actions work.
• A FlutterFlow project with a custom action already created.

Custom actions are powerful, but troubleshooting them can be tricky. This guide will help you systematically resolve common issues.

• Read the Error Message

  Always read the error message printed during test mode, compilation, or local build. The message often provides a clue about the potential issue.

• Common Troubleshooting Checklist

  • Action Name Mismatch

    Ensure the name in the action matches the custom action in your code.

    

    tip

    Use the Add BoilerPlate Code option to generate code with the correct action name.

  • Imports and Arguments

    • Check that all required imports are present.

    • Ensure arguments are defined in both the action settings and your code.

      

      Example:

      • Argument 1: Missing definition in settings panel

      • Argument 2: Correctly imported

      • Argument 3: Nullable selected, but not specified as nullable in code

        Follow the steps below to fix this issue:

        1. Manually update arguments in both the settings panel and your code.
        2. Use the Add BoilerPlate Code option (on web, copy only what you need; on desktop, it may replace all code).

        

  • Name Conflicts

    • Avoid using the same name for an action and its argument.

      

  • Reserved Keywords

    • Do not use Dart/Flutter reserved keywords as argument names. Examples: abstract, else, import, show, as, enum, in, static, this. FlutterFlow usually warns you, but double-check!

  • Return Type Mismatch

    • Ensure the custom action returns the correct data type as defined in the settings.

      

      The function should return the type specified in the settings panel.

  • Internal Library Imports

    • If importing internal libraries (example, ../../flutterflow), set Exclude from compilation to true if needed.

  • Pubspec Dependencies

    • Ensure your dependencies are declared in your code and are compatible with FlutterFlow.

      

      Check for:

      • Version conflicts (check on pub.dev)

      • Multiple versions of the same dependency

      • Conflicts with FlutterFlow's auto-imported dependencies

        

        

  • Code Errors:

    • Null values:

      Handle null values safely.

      int example = passingIntWhichMayBeNullable ?? 0;

    • Correct data types:

      Convert data types explicitly.

      String str = "5";
      int result = int.parse(str); // ✅

      Use .toString(), .toInt(), .toDouble() as needed.

    • Single elements vs arrays:

      Ensure you are not passing a single element where a list is expected, or vice versa.

  • Exclude from Compilation

    If this option is enabled, the code won’t be checked during build but can still run during test..

    

  • Duplicate Data Types/Structs

    Do not redefine data types or structs already defined in the data schema panel.

    

  • Callback Data Types

    Ensure callback actions return the correct data type.

    

Additional Resources

• Debugging with the Browser Console: Use the browser debug console for logic errors.
• FlutterFlow University Video: Custom Actions Video.
• Official Docs: Custom Actions | FlutterFlow Docs

tip

When in doubt, regenerate the boilerplate and compare with your code. Consistency between settings and code is key!