X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/9766efc33f1dc1d9a9e03ea6eb37985f20b1dd06..0cdd04ad993f86710bc5c9d9c8c12ec25a34ac71:/src/common/treebase.cpp

diff --git a/src/common/treebase.cpp b/src/common/treebase.cpp
index 38d242bf06..08220fa503 100644
--- a/src/common/treebase.cpp
+++ b/src/common/treebase.cpp
@@ -162,7 +162,9 @@ wxSize wxTreeCtrlBase::DoGetBestSize() const
     else // use precise, if potentially slow, size computation method
     {
         // iterate over all items recursively
-        wxGetBestTreeSize(this, GetRootItem(), size);
+        wxTreeItemId idRoot = GetRootItem();
+        if ( idRoot.IsOk() )
+            wxGetBestTreeSize(this, idRoot, size);
     }
 
     // need some minimal size even for empty tree