Catch attempts to create a window with itself as parent.

This doesn't happen often but when it does, the results are catastrophic and
not always easy to debug, so try catch this as soon as possible.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@73139 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

diff --git a/include/wx/window.h b/include/wx/window.h
index af1b4886eab7ab9a7c7befb5626fffb3d95a73cd..443f0366e72cce01d2a0c6554a9eaec3639f2c4a 100644 (file)
--- a/include/wx/window.h
+++ b/include/wx/window.h
@@ -752,7 +752,7 @@ public:
     bool IsDescendant(wxWindowBase* win) const;
 
         // it doesn't really change parent, use Reparent() instead
     bool IsDescendant(wxWindowBase* win) const;
 
         // it doesn't really change parent, use Reparent() instead

-    void SetParent( wxWindowBase *parent ) { m_parent = (wxWindow *)parent; }
+    void SetParent( wxWindowBase *parent );

         // change the real parent of this window, return true if the parent
         // was changed, false otherwise (error or newParent == oldParent)
     virtual bool Reparent( wxWindowBase *newParent );
         // change the real parent of this window, return true if the parent
         // was changed, false otherwise (error or newParent == oldParent)
     virtual bool Reparent( wxWindowBase *newParent );

diff --git a/src/common/wincmn.cpp b/src/common/wincmn.cpp
index 13370f51c630f8e449b635438ae1240d04c2449a..cd24e50ed0f476bc1b9deee00c865ef76b89ea3b 100644 (file)
--- a/src/common/wincmn.cpp
+++ b/src/common/wincmn.cpp
@@ -1317,6 +1317,20 @@ void wxWindowBase::RemoveChild(wxWindowBase *child)
     child->SetParent(NULL);
 }
 
     child->SetParent(NULL);
 }
 

+void wxWindowBase::SetParent(wxWindowBase *parent)
+{
+    // This assert catches typos which may result in using "this" instead of
+    // "parent" when creating the window. This doesn't happen often but when it
+    // does the results are unpleasant because the program typically just
+    // crashes when due to a stack overflow or something similar and this
+    // assert doesn't cost much (OTOH doing a more general check that the
+    // parent is not one of our children would be more expensive and probably
+    // not worth it).
+    wxASSERT_MSG( parent != this, wxS("Can't use window as its own parent") );
+
+    m_parent = (wxWindow *)parent;
+}
+

 bool wxWindowBase::Reparent(wxWindowBase *newParent)
 {
     wxWindow *oldParent = GetParent();
 bool wxWindowBase::Reparent(wxWindowBase *newParent)
 {
     wxWindow *oldParent = GetParent();