Filament: Format Table Column Value with Custom Helper Method

If you want to format a table column value in a custom way, you can define the formatting method as a helper and then use it with ->formatStateUsing() in the column.

Here's an example from Dinero open-source project:

app/Filament/Resources/WalletResource.php

class WalletResource extends Resource
{
    public static function table(Table $table): Table
    {
        return $table
            ->columns([
                // ... other columns
                Tables\Columns\TextColumn::make('currency_code')
                    ->label(__('wallets.fields.currency_code'))
                    ->formatStateUsing(fn (string $state): string => country_with_currency_and_symbol($state)) 
                    ->sortable(),
            ]);
    }
}

The country_with_currency_and_symbol() method is defined in this file:

app/Support/helpers.php

use Illuminate\Support\Collection;
 
function country_with_currency_and_symbol($state = null): Collection|string {
    $countries = collect(countries())->mapWithKeys(function ($country) {
        try {
            $currency = currency($country['currency']);
            return [
                $country['currency'] => sprintf('%s - %s - %s (%s)',$country['name'], $currency->getCurrency(), $currency->getName(), $currency->getSymbol())
            ];
        } catch (\Exception $e) {
            return [null => null];
        }
    })->filter();
 
    if($state) {
        return $countries->get($state);
    }
 
    return $countries;
}

Then this file is auto-loaded with Composer:

composer.json

{
    "autoload": {
        "files": [
            "app/Support/helpers.php"
        ]
    },
}

Visual result:

Link to the Filament docs