From ec09e18d3544bb333f367db7f7e8f410d81e5b14 Mon Sep 17 00:00:00 2001
From: Vadim Zeitlin <vadim@wxwidgets.org>
Date: Wed, 14 Jun 2006 18:37:48 +0000
Subject: [PATCH] more fixes to OnHelp() to avoid infinite recursion when
 handling help events

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@39729 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
---
 src/common/bookctrl.cpp | 66 +++++++++++++++++++++++++++--------------
 1 file changed, 43 insertions(+), 23 deletions(-)

diff --git a/src/common/bookctrl.cpp b/src/common/bookctrl.cpp
index a0c4781508..d1e7bcbe01 100644
--- a/src/common/bookctrl.cpp
+++ b/src/common/bookctrl.cpp
@@ -162,41 +162,61 @@ wxSize wxBookCtrlBase::DoGetBestSize() const
 }
 
 #if wxUSE_HELP
+
 void wxBookCtrlBase::OnHelp(wxHelpEvent& event)
 {
-    // ignore the events not coming from the book control itself, otherwise we
-    // could attempt to redirect a help event generated by one of our pages
-    // back to the same page resulting in an infinite loop
-    if ( event.GetEventObject() != this )
+    // determine where does this even originate from to avoid redirecting it
+    // back to the page which generated it (resulting in an infinite loop)
+
+    // notice that we have to check in the hard(er) way instead of just testing
+    // if the event object == this because the book control can have other
+    // subcontrols inside it (e.g. wxSpinButton in case of a notebook in wxUniv)
+    wxWindow *source = wxStaticCast(event.GetEventObject(), wxWindow);
+    while ( source && source->GetParent() != this )
     {
-        event.Skip();
-        return;
+        source = source->GetParent();
     }
 
-    // find the corresponding page
-    wxWindow *page = NULL;
-
-    if ( event.GetOrigin() == wxHelpEvent::Origin_HelpButton )
+    if ( source && m_pages.Index(source) == wxNOT_FOUND )
     {
-        // show help for the page under the mouse
-        const int pagePos = HitTest(ScreenToClient(event.GetPosition()));
+        // this event is for the book control itself, redirect it to the
+        // corresponding page
+        wxWindow *page = NULL;
 
-        if ( pagePos != wxNOT_FOUND)
+        if ( event.GetOrigin() == wxHelpEvent::Origin_HelpButton )
         {
-            page = GetPage((size_t)pagePos);
+            // show help for the page under the mouse
+            const int pagePos = HitTest(ScreenToClient(event.GetPosition()));
+
+            if ( pagePos != wxNOT_FOUND)
+            {
+                page = GetPage((size_t)pagePos);
+            }
+        }
+        else // event from keyboard or unknown source
+        {
+            // otherwise show the current page help
+            page = GetCurrentPage();
         }
-    }
-    else // event.GetOrigin() != wxHelpEvent::Origin_HelpButton
-    {
-        // if event came from keyboard then show the current page help
-        page = GetCurrentPage();
-    }
 
-    if ( !page || !page->GetEventHandler()->ProcessEvent(event) )
-    {
-        event.Skip();
+        if ( page )
+        {
+            // change event object to the page to avoid infinite recursion if
+            // we get this event ourselves if the page doesn't handle it
+            event.SetEventObject(page);
+
+            if ( page->GetEventHandler()->ProcessEvent(event) )
+            {
+                // don't call event.Skip()
+                return;
+            }
+        }
     }
+    //else: event coming from one of our pages already
+
+    event.Skip();
 }
+
 #endif // wxUSE_HELP
 
 // ----------------------------------------------------------------------------
-- 
2.45.2