select2 依赖于另一个字段的字段

Question

我想实现本教程中的代码展示：

https://backpackforlaravel.com/docs/4.1/crud-how-to#add-a-select2-field-that-depends-on-another-field

但是，此行返回null值：

$form = collect($request->input('form'))->pluck('value', 'name');

我不知道我是否应该input('form')在这里使用它，因为它取自版本 3.4 的文档有人知道它是否适用于版本 4.

克鲁德控制器：

// CRUD::field('sub_district_id')

//     ->type('select2')

//     ->label('Kecamatan')

//     ->entity('sub_district')

//     ->attribute('sub_district_name')

//     ->model('App\Models\SubDistrict')

//     ->wrapper(['class' => 'form-group col-md-6']);

CRUD::field('sub_district_id')

    ->type('relationship')

    ->label('Kecamatan')

    ->attribute('sub_district_name')

    ->include_all_form_fields(true)

    ->wrapper(['class' => 'form-group col-md-6']);

CRUD::field('village_id')

    ->type('select2_from_ajax')

    ->label('Desa/Kelurahan')

    ->entity('village')

    ->attribute('village_name')

    ->model("App\Models\Village")

    ->wrapper(['class' => 'form-group col-md-6'])

    ->data_source(url('api/village'))

    ->placeholder('Pilih Desa/Kelurahan')

    ->minimum_input_length(0)

    ->dependencies(['sub_district_id'])

    ->method('GET'); // optional - HTTP method to use for the AJAX call (GET, POST)

接口控制器：

$search_term = $request->input('q');

$form = collect($request->input('form'))->pluck('value', 'name');

// dump($form);

$options = Village::query();

if (!$form['sub_district_id']) {

    return [];

}

// if a category has been selected, only show articles in that category

if ($form['sub_district_id']) {

    $options = $options->where('sub_district_id', $form['sub_district_id']);

}

if ($search_term) {

    $results = $options->where('village_name', 'LIKE', '%' . $search_term . '%')->paginate(10);

} else {

    $results = $options->paginate(10);

}

return $options->paginate(10);