[FormBuilderSearchableDropdown]: Another exception was thrown: 'package:form_builder_extra_fields/src/fields/form_builder_searchable_dropdown.dart': Failed assertion: line 128 pos 16: 'T == String || compareFn != null': is not true.

[dedyksuntoro]

Is there an existing issue for this?

• I have searched the existing issues

Package/Plugin version

10.1.0

Platforms

• Android
• iOS
• Linux
• MacOS
• Web
• Windows

Flutter doctor

Flutter doctor

Doctor summary (to see all details, run flutter doctor -v):
[√] Flutter (Channel stable, 3.13.9, on Microsoft Windows [Version 10.0.22621.2283], locale en-ID)
[√] Windows Version (Installed version of Windows is version 10 or higher)
[√] Android toolchain - develop for Android devices (Android SDK version 33.0.0)
[√] Chrome - develop for the web
[√] Visual Studio - develop Windows apps (Visual Studio Community 2022 17.1.0)
[√] Android Studio (version 2022.3)
[√] VS Code (version 1.84.2)
[√] Connected device (4 available)
[√] Network resources

• No issues found!

Minimal code example

Code sample

List selectBan = [];

_futureSelectSerahTerimaKendaraanListBan =
    _apiDatabase.geSelectSerahTerimaKendaraanListBan();
_futureSelectSerahTerimaKendaraanListBan.then((value) {
  setState(() {
    selectBan = value;
  });
});

FormBuilderSearchableDropdown(
  name: 'al',
  decoration: InputDecoration(
    label: Text('AL'),
    border: OutlineInputBorder(),
  ),
  items: selectBan
      .map(
        (e) => DropdownMenuItem(
          value: e.id,
          child: Text(
            e.sparepart.toString(),
          ),
        ),
      )
      .toList(),
  onChanged: (value) {},
),

Current Behavior

Error Message:
Another exception was thrown: 'package:form_builder_extra_fields/src/fields/form_builder_searchable_dropdown.dart': Failed assertion: line 128 pos 16: 'T == String || compareFn != null': is not true.

Expected Behavior

Maybe this can be fixed soon

Steps To Reproduce

Aditional information

No response

[enjat26]

i think this issue because condition (T == String || compareFn != null) not met, you can add or add compareFn: (item1, item2) => true,

like this :

Widget _masterCheckPoint() {
return FormBuilderSearchableDropdown(
name: 'mstr_id',
decoration: const InputDecoration(
hintText: 'Check Point',
label: Text('Check Point'),
),
validator: FormBuilderValidators.compose([
FormBuilderValidators.required(),
]),
asyncItems: (String? filter) => _controller.getMasterCheckPoint(filter),
compareFn: (item1, item2) => true,
popupProps: const PopupProps.menu(
showSearchBox: true,
),
);
}

[jesse-shaw-egeo]

This is not a bug, either your generic type has to be a string, or you have to implement the custom compare function.