From ca7b02b76a430bb4b911d94f88c9136090f7690e Mon Sep 17 00:00:00 2001
From: Dirkster99 <Dirk.Bahle@gmx.de>
Date: Thu, 19 Jul 2018 21:42:01 +0200
Subject: [PATCH] Check before Close in InternalClose #/1310
 https://github.com/xceedsoftware/wpftoolkit/issues/1310

---
 .../Controls/LayoutFloatingWindowControl.cs                | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/source/Components/Xceed.Wpf.AvalonDock/Controls/LayoutFloatingWindowControl.cs b/source/Components/Xceed.Wpf.AvalonDock/Controls/LayoutFloatingWindowControl.cs
index badc94bd..1cf0da19 100644
--- a/source/Components/Xceed.Wpf.AvalonDock/Controls/LayoutFloatingWindowControl.cs
+++ b/source/Components/Xceed.Wpf.AvalonDock/Controls/LayoutFloatingWindowControl.cs
@@ -360,6 +360,13 @@ protected virtual IntPtr FilterMessage( IntPtr hwnd, int msg, IntPtr wParam, Int
 
     internal void InternalClose()
     {
+      // Check before Close in InternalClose
+      // https://github.com/xceedsoftware/wpftoolkit/issues/1310
+      if( _internalCloseFlag )
+      {
+        return;
+      }
+
       _internalCloseFlag = true;
       Close();
     }