From c2fecf7c70bcae9028126787e5b82e390f683966 Mon Sep 17 00:00:00 2001
From: Alessandro Ranellucci <aar@cpan.org>
Date: Tue, 21 Mar 2017 20:29:36 +0100
Subject: [PATCH] Minor fix to prevent the Cancel button from showing when
 there are no objects

---
 lib/Slic3r/GUI/Plater.pm | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/lib/Slic3r/GUI/Plater.pm b/lib/Slic3r/GUI/Plater.pm
index 59fa49659..797e7c01f 100644
--- a/lib/Slic3r/GUI/Plater.pm
+++ b/lib/Slic3r/GUI/Plater.pm
@@ -1343,9 +1343,13 @@ sub start_background_process {
     my ($self) = @_;
     
     return if !$Slic3r::have_threads;
-    return if !@{$self->{objects}};
     return if $self->{process_thread};
     
+    if (!@{$self->{objects}}) {
+        $self->on_process_completed;
+        return;
+    }
+    
     # It looks like declaring a local $SIG{__WARN__} prevents the ugly
     # "Attempt to free unreferenced scalar" warning...
     local $SIG{__WARN__} = Slic3r::GUI::warning_catcher($self);