multiSelect

Creates multiple select input.

FormItem::multiSelect('categories', 'Categories')

Providing Data

With array:

->list(['First', 'Second', 'Third])

With enum (use array values as keys):

->enum(['First', 'Second', 'Third])

With class:

->list(\Foo\MyModel::class)

MyModel must implement public static function getList() and return array.

Providing Selected Items

->value('categories.article_id')

Saving Data

Create new mutator method in your model. Here is an example:

public function setCategoriesAttribute($categories)
{
    $this->categories()->detach();
    if ( ! $categories) return;
    if ( ! $this->exists) $this->save();

    $this->categories()->attach($categories);
}

categories() method creates belongs-to-many relation in this case.