Add item grid to backend order form

Creates a new form widget for that lists items, and uses this on
the backend to display order items. Read-only at the moment, but
it's better than nothing... Also set a blank label for the field

Plugin.php

@@ -80,6 +80,16 @@ public function registerNavigation()
         ];
     }
 
+    public function registerFormWidgets()
+    {
+        return [
+            'Dshoreman\Shop\FormWidgets\ItemGrid' => [
+                'label' => 'Order Item Grid',
+                'alias' => 'itemgrid',
+            ],
+        ];
+    }
+
     public function registerPermissions()
     {
         return [

formwidgets/ItemGrid.php

@@ -0,0 +1,28 @@
+<?php namespace Dshoreman\Shop\FormWidgets;
+
+use Backend\Classes\FormWidgetBase;
+use Backend\Widgets\Grid;
+
+class ItemGrid extends FormWidgetBase {
+
+    public function widgetDetails()
+    {
+        return [
+            'name' => 'Item Grid',
+            'description' => 'Renders a grid of items from an order',
+        ];
+    }
+
+    public function render()
+    {
+        $this->prepareVars();
+
+        return $this->makePartial('itemgrid');
+    }
+
+    public function prepareVars()
+    {
+        $this->vars['items'] = json_decode($this->formField->value);
+    }
+
+}

formwidgets/itemgrid/partials/_itemgrid.htm

@@ -0,0 +1,22 @@
+<table class="table table-condensed">
+    <thead>
+        <tr>
+            <th>Item #</th>
+            <th>Name</th>
+            <th>Price</th>
+            <th>Quantity</th>
+            <th>Subtotal</th>
+        </tr>
+    </thead>
+    <tbody>
+        <?php foreach ($items as $item): ?>
+        <tr>
+            <td><?= $item->id ?></td>
+            <td><?= $item->name ?></td>
+            <td><?= $item->price ?></td>
+            <td><?= $item->qty ?></td>
+            <td><?= $item->subtotal ?></td>
+        </tr>
+        <?php endforeach; ?>
+    </tbody>
+</table>

models/order/fields.yaml

@@ -82,8 +82,9 @@ tabs:
             tab: Addresses
 
         items:
-            label: Order Items
+            label:
             tab: Items
+            type: itemgrid
         total:
             label: Order Value
             span: right