add nova

nova/src/ManagesPresets.php

@@ -0,0 +1,41 @@
+<?php
+
+namespace Laravel\Nova;
+
+trait ManagesPresets
+{
+    /**
+     * Indicates the preset the field should use.
+     *
+     * @var string
+     */
+    public $preset = 'default';
+
+    /**
+     * Define the preset the field should use, optionally providing a new preset class to add.
+     *
+     * @param  string  $preset
+     * @param  string|null  $presetClass
+     * @return $this
+     */
+    public function preset($preset, $presetClass = null)
+    {
+        if (! is_null($presetClass)) {
+            $this->presets[$preset] = $presetClass;
+        }
+
+        $this->preset = $preset;
+
+        return $this;
+    }
+
+    /**
+     * Create a new instance of the configured preset.
+     *
+     * @return object
+     */
+    public function newPreset()
+    {
+        return new $this->presets[$this->preset];
+    }
+}