Added ability to use a specific PayPal API.

src/PayPalFacadeAccessor.php

@@ -1,11 +1,46 @@
 <?php namespace Srmklive\PayPal;
 
+use Srmklive\PayPal\Services\AdaptivePayments;
 use Srmklive\PayPal\Services\ExpressCheckout;
 
 class PayPalFacadeAccessor
 {
+    /**
+     * PayPal API provider object
+     *
+     * @var $provider
+     */
+    public static $provider;
+
+    /**
+     * Get specific PayPal API provider object to use
+     *
+     * @return ExpressCheckout|AdaptivePayments
+     */
     public static function getProvider()
     {
-        return new ExpressCheckout;
+        if (empty(self::$provider))
+            return new ExpressCheckout;
+        else
+            return self::$provider;
+    }
+
+    /**
+     * Set specific PayPal API to use
+     *
+     * @param string $option
+     * @return ExpressCheckout|AdaptivePayments
+     */
+    public static function setProvider($option = '')
+    {
+        if (!in_array($option, ['express_checkout', 'adaptive_payments']))
+            $option = 'express_checkout';
+
+        if ($option == 'express_checkout')
+            self::$provider = new ExpressCheckout;
+        elseif ($option == 'adaptive_payments')
+            self::$provider = new AdaptivePayments;
+
+        return self::getProvider();
     }
 }