From bdeb0aab4f67f08bce0c8cffc2f833478dd65f26 Mon Sep 17 00:00:00 2001
From: Guy Marriott <guy@scopey.co.nz>
Date: Mon, 29 Jun 2020 12:09:10 -0700
Subject: [PATCH] Merge pull request #9565 from tom890180/check_items_exist

---
 .../GridField/GridFieldDetailForm_ItemRequest.php      | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/Forms/GridField/GridFieldDetailForm_ItemRequest.php b/src/Forms/GridField/GridFieldDetailForm_ItemRequest.php
index 3e35bcfeb..1f204fe90 100644
--- a/src/Forms/GridField/GridFieldDetailForm_ItemRequest.php
+++ b/src/Forms/GridField/GridFieldDetailForm_ItemRequest.php
@@ -452,8 +452,10 @@ class GridFieldDetailForm_ItemRequest extends RequestHandler
             if ($toplevelController->hasMethod('Backlink')) {
                 $backlink = $toplevelController->Backlink();
             } elseif ($this->popupController->hasMethod('Breadcrumbs')) {
-                $parents = $this->popupController->Breadcrumbs(false)->items;
-                $backlink = array_pop($parents)->Link;
+                $parents = $this->popupController->Breadcrumbs(false);
+                if ($parents && $parents = $parents->items) {
+                    $backlink = array_pop($parents)->Link;
+                }
             }
         }
         if (!$backlink) {
@@ -774,6 +776,10 @@ class GridFieldDetailForm_ItemRequest extends RequestHandler
         /** @var ArrayList $items */
         $items = $this->popupController->Breadcrumbs($unlinked);
 
+        if (!$items) {
+            $items = new ArrayList();
+        }
+
         if ($this->record && $this->record->ID) {
             $title = ($this->record->Title) ? $this->record->Title : "#{$this->record->ID}";
             $items->push(new ArrayData([