Laravel Backpack select2_from_ajax select change the result and default value

Question

For the backpack-demo, I would like to show the ID and Title together. For the search result no issue, selected at the select2 also no issue, the problem is after save, it will not display, it become blank.

How can I set it?

Like below

backpack-demo/app/Http/Controllers/Admin/MonsterCrudController.php

[ // select2_from_ajax: 1-n relationship
                'label'                => 'Select2_from_ajax', // Table column heading
                'type'                 => 'select2_from_ajax',
                'name'                 => 'select2_from_ajax', // the column that contains the ID of that connected entity;
                'entity'               => 'article', // the method that defines the relationship in your Model
                'attribute'            => 'id_title', // foreign key attribute that is shown to user
                'model'                => "BackpackNewsCRUDappModelsArticle", // foreign key model
                'data_source'          => url('api/article'), // url to controller search function (with /{id} should return model)
                'placeholder'          => 'Select an article', // placeholder for the select
                'minimum_input_length' => 2, // minimum characters to type before querying results
                'tab'                  => 'Relationships',
                'wrapperAttributes'    => ['class' => 'form-group col-md-12'],
            ],

backpack-demo/app/Http/Controllers/Api/ArticleController.php

        if ($search_term) {
            return Article::
            selectRaw("CONCAT('Article ID: ', id,' | Title: ', Title) AS id_title, articles.*")
            ->where('title', 'LIKE', '%'.$search_term.'%')->paginate(10);
        } else {
            return Article::selectRaw("CONCAT('Article ID: ', id,' | Title: ', Title) AS id_title, articles.*")
            ->paginate(10);
        }

Answer 1

The solution is at the Article Model create another accessor function

public function getIdTitleAttribute()
{
    return 'Article ID: ' . $this->id . ' | Title: ' . $this->title;
}