From: Vadim Zeitlin <vadim@wxwidgets.org>
Date: Tue, 27 Aug 2002 17:03:56 +0000 (+0000)
Subject: fixed crashes in Push/PopEventHandler() if the current handler is NULL
X-Git-Url: https://git.saurik.com/wxWidgets.git/commitdiff_plain/3a074ba8f6df3a80e0d6a89d138b1a9caa7c8366

fixed crashes in Push/PopEventHandler() if the current handler is NULL


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@16813 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
---

diff --git a/src/common/wincmn.cpp b/src/common/wincmn.cpp
index 6f94732748..dd19223457 100644
--- a/src/common/wincmn.cpp
+++ b/src/common/wincmn.cpp
@@ -722,8 +722,13 @@ bool wxWindowBase::Reparent(wxWindowBase *newParent)
 
 void wxWindowBase::PushEventHandler(wxEvtHandler *handler)
 {
-    handler->SetNextHandler(GetEventHandler());
-    GetEventHandler()->SetPreviousHandler(handler);
+    wxEvtHandler *handlerOld = GetEventHandler();
+
+    handler->SetNextHandler(handlerOld);
+
+    if ( handlerOld )
+        GetEventHandler()->SetPreviousHandler(handler);
+
     SetEventHandler(handler);
 }
 
@@ -734,8 +739,11 @@ wxEvtHandler *wxWindowBase::PopEventHandler(bool deleteHandler)
     {
         wxEvtHandler *handlerB = handlerA->GetNextHandler();
         handlerA->SetNextHandler((wxEvtHandler *)NULL);
-        handlerB->SetPreviousHandler((wxEvtHandler *)NULL);
+
+        if ( handlerB )
+            handlerB->SetPreviousHandler((wxEvtHandler *)NULL);
         SetEventHandler(handlerB);
+
         if ( deleteHandler )
         {
             delete handlerA;