# Relationships

In addition to the variety of fields we've already discussed, Nova has full support for all of Laravel's relationships. Once you add relationship fields to your Nova resources, you'll start to experience the full power of the Nova dashboard, as the resource detail page will allow you to quickly view and search a resource's related models:

Detail page Relationship

# HasOne

The HasOne field corresponds to a hasOne Eloquent relationship. For example, let's assume a User model hasOne Address model. We may add the relationship to our User Nova resource like so:

use Laravel\Nova\Fields\HasOne;

HasOne::make('Address')

Like other types of fields, relationship fields will automatically "snake case" the displayable name of the field to determine the underlying relationship method / attribute. However, you may explicitly specify the name of the relationship method by passing it as the second argument to the field's make method:

HasOne::make('Dirección', 'address')

# HasMany

The HasMany field corresponds to a hasMany Eloquent relationship. For example, let's assume a User model hasMany Post models. We may add the relationship to our User Nova resource like so:

use Laravel\Nova\Fields\HasMany;

HasMany::make('Posts')

Once the field has been added to your resource, it will be displayed on the resource's detail page.

Use Plural Resource Name

When defining HasMany relationship, make sure to use the plural form of the relation so Nova can infer the correct singular resource name:

// Do this
HasMany::make('Posts');

// Not this
HasMany::make('Post');

# BelongsTo

The BelongsTo field corresponds to a belongsTo Eloquent relationship. For example, let's assume a Post model belongsTo a User model. We may add the relationship to our Post Nova resource like so:

use Laravel\Nova\Fields\BelongsTo;

BelongsTo::make('User')

Customizing Resource Classes

You can customize the resource class used by the relation field by setting the second and third parameters of the make method:

BelongsTo::make('Author', 'author', 'App\Nova\User');

# Nullable Relationships

If you would like your BelongsTo relationship to be nullable, chain the nullable method onto the field's definition:

use Laravel\Nova\Fields\BelongsTo;

BelongsTo::make('User')->nullable()

# Title Attributes

When a BelongsTo field is shown on a resource creation / update page, a drop-down selection menu or search menu will display the "title" of the resource. For example, a User resource may use the name attribute as its title. Then, when the resource is shown in a BelongsTo selection menu, that attribute will be displayed:

Belongs To Title

To customize the "title" attribute of a resource, you may define a title property on the resource class:

public static $title = 'name';

Alternatively, you may override the resource's title method:

/**
 * Get the value that should be displayed to represent the resource.
 *
 * @return string
 */
public function title()
{
    return $this->name;
}

# BelongsToMany

The BelongsToMany field corresponds to a belongsToMany Eloquent relationship. For example, let's assume a User model belongsToMany Role models. We may add the relationship to our User Nova resource like so:

use Laravel\Nova\Fields\BelongsToMany;

BelongsToMany::make('Roles')

Once the field has been added to your resource, it will be displayed on the resource's detail page.

# Pivot Fields

If your belongsToMany relationship interacts with additional "pivot" fields that are stored on the intermediate table of the many-to-many relationship, you may also attach those to your BelongsToMany Nova relationship. Once these fields are attached to the relationship field, and the relationship has been defined on both sides, they will be displayed on the related resource index.

For example, let's assume our User model belongsToMany Role models. On our role_user intermediate table, let's imagine we have a notes field that contains some simple text notes about the relationship. We can attach this pivot field to the BelongsToMany field using the fields method:

BelongsToMany::make('Roles')
    ->fields(function () {
        return [
            Text::make('Notes'),
        ];
    })

It is likely we would also define this field on the inverse of the relationship. So, if we define the BelongsToMany field on the User resource, we would define its inverse on the Role resource:

BelongsToMany::make('Users')
    ->fields(function () {
        return [
            Text::make('Notes'),
        ];
    })

Since defining the field on both ends of the relationship can cause some code duplication, Nova allows you to pass an invokable object to the fields method:

BelongsToMany::make('Users')->fields(new RoleUserFields)

In this example, the RoleUserFields class would be a simple, invokable class that returns the array of pivot fields:

<?php

namespace App\Nova;

use Laravel\Nova\Fields\Text;

class RoleUserFields
{
    /**
     * Get the pivot fields for the relationship.
     *
     * @return array
     */
    public function __invoke()
    {
        return [
            Text::make('Notes'),
        ];
    }
}

# Pivot Actions

Typically, Nova actions operate on a resource. However, you may also attach actions to belongsToMany fields so that they can operate on pivot / intermediate table records. To accomplish this, you may chain the actions method onto your field's definition:

BelongsToMany::make('Roles')
    ->actions(function () {
        return [
            new Actions\MarkAsActive,
        ];
    })

Once the action has been attached to the field, you will be able to select the action and execute it from the relationship index on the parent's resource detail page.

Actions

To learn more about Nova actions, check out the complete action documentation.

# Title Attributes

When a BelongsToMany field is shown on a resource creation / update page, a drop-down selection menu or search menu will display the "title" of the resource. For example, a Role resource may use the name attribute as its title. Then, when the resource is shown in a BelongsToMany selection menu, that attribute will be displayed:

Belongs To Many Title

To customize the "title" attribute of a resource, you may define a title property on the resource class:

public static $title = 'name';

Alternatively, you may override the resource's title method:

/**
 * Get the value that should be displayed to represent the resource.
 *
 * @return string
 */
public function title()
{
    return $this->name;
}

# MorphOne

The MorphOne field corresponds to a morphOne Eloquent relationship. For example, let's assume a Post has a one-to-one polymorphic relationship with the Image model. We may add the relationship to our Post Nova resource like so:

use Laravel\Nova\Fields\MorphOne;

MorphOne::make('Image')

# MorphMany

The MorphMany field corresponds to a morphMany Eloquent relationship. For example, let's assume a Post has a one-to-many polymorphic relationship with the Comment model. We may add the relationship to our Post Nova resource like so:

use Laravel\Nova\Fields\MorphMany;

MorphMany::make('Comments')

# MorphTo

The MorphTo field corresponds to a morphTo Eloquent relationship. For example, let's assume a Comment model has a polymorphic relationship with both the Post and Video models. We may add the relationship to our Comment Nova resource like so:

use App\Nova\Post;
use App\Nova\Video;
use Laravel\Nova\Fields\MorphTo;

MorphTo::make('Commentable')->types([
    Post::class,
    Video::class,
])

As you can see in the example above, the types method is used to instruct the MorphTo field what types of resources it may be associated with. Nova will use this information to populate the MorphTo field's type selection menu on the creation and update pages:

Morph To Type

MorphTo Title Attributes

When a MorphTo field is shown on a resource creation / update page, the title attributes of the available resources will automatically be displayed.

# Nullable Relationships

If you would like your MorphTo relationship to be nullable, chain the nullable method onto the field's definition:

use App\Nova\Post;
use App\Nova\Video;
use Laravel\Nova\Fields\MorphTo;

MorphTo::make('Commentable')->types([
    Post::class,
    Video::class,
])->nullable()

# MorphToMany

The MorphToMany field corresponds to a morphToMany Eloquent relationship. For example, let's assume a Post has a many-to-many polymorphic relationship with the Tag model. We may add the relationship to our Post Nova resource like so:

use Laravel\Nova\Fields\MorphToMany;

MorphToMany::make('Tags')

# Pivot Fields

If your morphToMany relationship interacts with additional "pivot" fields that are stored on the intermediate table of the many-to-many relationship, you may also attach those to your MorphToMany Nova relationship. Once these fields are attached to the relationship field, they will be displayed on the related resource index.

For example, on our taggables intermediate table, let's imagine we have a notes field that contains some simple text notes about the relationship. We can attach this pivot field to the MorphToMany field using the fields method:

MorphToMany::make('Tags')
    ->fields(function () {
        return [
            Text::make('Notes'),
        ];
    })

It is likely we would also define this field on the inverse of the relationship. So, if we define the MorphToMany field on the Post resource, we would define it's inverse on the Tag resource:

MorphToMany::make('Posts')
    ->fields(function () {
        return [
            Text::make('Notes'),
        ];
    })

Since defining the field on both ends of the relationship can cause some code duplication, Nova allows you to pass an invokable object to the fields method:

MorphToMany::make('Users')->fields(new TaggableFields)

In this example, the TaggableFields class would be a simple, invokable class that returns the array of pivot fields:

<?php

namespace App\Nova;

use Laravel\Nova\Fields\Text;

class TaggableFields
{
    /**
     * Get the pivot fields for the relationship.
     *
     * @return array
     */
    public function __invoke()
    {
        return [
            Text::make('Notes'),
        ];
    }
}

# Title Attributes

When a MorphToMany field is shown on a resource creation / update page, a drop-down selection menu or search menu will display the "title" of the resource. For example, a Tag resource may use the name attribute as its title. Then, when the resource is shown in a MorphToMany selection menu, that attribute will be displayed:

Morph To Many Title

To customize the "title" attribute of a resource, you may define a title property on the resource class:

public static $title = 'name';

Alternatively, you may override the resource's title method:

/**
 * Get the value that should be displayed to represent the resource.
 *
 * @return string
 */
public function title()
{
    return $this->name;
}

# Searchable Relations

By default, when the BelongsTo, MorphTo, and MorphToMany relationship fields are shown on a resource creation / update page, a simple drop-down selection menu will be displayed. However, this can quickly become cumbersome if a resource model has many records. For example, imagine a drop-down selection menu populated with over 10,000 users!

Instead of displaying a drop-down selection menu, you may mark your relationships as searchable. When a relationship is marked as searchable, a beautiful search input control will be displayed instead:

Belongs To Search

To mark as relationship as searchable, chain the searchable method onto the field's definition:

BelongsTo::make('User')->searchable()