add navs fieldtype

src/Fieldtypes/Navs.php

@@ -0,0 +1,62 @@
+<?php
+
+namespace Statamic\Fieldtypes;
+
+use Statamic\CP\Column;
+use Statamic\Facades\GraphQL;
+use Statamic\Facades\Nav;
+use Statamic\GraphQL\Types\NavType;
+
+class Navs extends Relationship
+{
+    protected $categories = ['relationship'];
+    protected $canEdit = false;
+    protected $canCreate = false;
+    protected $canSearch = false;
+    protected $statusIcons = false;
+
+    protected function toItemArray($id, $site = null)
+    {
+        if ($nav = Nav::findByHandle($id)) {
+            return [
+                'title' => $nav->title(),
+                'id' => $nav->handle(),
+            ];
+        }
+
+        return $this->invalidItemArray($id);
+    }
+
+    public function getIndexItems($request)
+    {
+        return Nav::all()->sortBy('title')->map(function ($nav) {
+            return [
+                'id' => $nav->handle(),
+                'title' => $nav->title(),
+            ];
+        })->values();
+    }
+
+    protected function getColumns()
+    {
+        return [
+            Column::make('title'),
+        ];
+    }
+
+    protected function augmentValue($value)
+    {
+        return Nav::findByHandle($value);
+    }
+
+    public function toGqlType()
+    {
+        $type = GraphQL::type(NavType::NAME);
+
+        if ($this->config('max_items') !== 1) {
+            $type = GraphQL::listOf($type);
+        }
+
+        return $type;
+    }
+}

src/Providers/ExtensionServiceProvider.php

@@ -76,6 +76,7 @@ class ExtensionServiceProvider extends ServiceProvider
         Fieldtypes\Lists::class,
         Fieldtypes\Markdown::class,
         Fieldtypes\Markdown\Buttons::class,
+        Fieldtypes\Navs::class,
         Fieldtypes\NestedFields::class,
         Fieldtypes\Radio::class,
         Fieldtypes\Range::class,