From f0d5e9541254f5e0ae81dc55fb667d101cf55a6a Mon Sep 17 00:00:00 2001
From: John Roberts <johnr@iinet.net.au>
Date: Wed, 24 Jan 2018 16:40:26 +0100
Subject: [PATCH] Fix crash when clearing read-only wxOwnerDrawnComboBox

Check that we have an associated text entry before clearing it.

Fixes a crash introduced by 72fe57ec182ba0bc9a51ad27adc883a945d39b81
without reverting it as it still seems reasonable to use Clear() here.

Closes #18013.
---
 src/generic/odcombo.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/generic/odcombo.cpp b/src/generic/odcombo.cpp
index 89ec54016b..d77833bb16 100644
--- a/src/generic/odcombo.cpp
+++ b/src/generic/odcombo.cpp
@@ -991,7 +991,9 @@ void wxOwnerDrawnComboBox::DoClear()
 
     GetVListBoxComboPopup()->Clear();
 
-    wxTextEntry::Clear();
+    // There is no text entry when using wxCB_READONLY style, so test for it.
+    if ( GetTextCtrl() )
+        wxTextEntry::Clear();
 }
 
 void wxOwnerDrawnComboBox::Clear()