Fix setting default file name in wxGenericFileDirButton in wxGTK.

Set the default directory first, if it's specified, and the file name later to
ensure that it's interpreted relatively to this directory. Otherwise we could
have a mismatch between the directory shown in the dialog and its initial
path.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@70732 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/generic/filepickerg.cpp

@@ -139,14 +139,19 @@ wxDialog *wxGenericFileButton::CreateDialog()
                                         GetDialogStyle()
                                      );
 
-    // this sets both the default folder and the default file of the dialog
-    dialog->SetPath(m_path);
-
     // If there is no default file or if it doesn't have any path, use the
     // explicitly set initial directory.
+    //
+    // Notice that it is important to call this before SetPath() below as if we
+    // do have m_initialDir and no directory in m_path, we need to interpret
+    // the path as being relative with respect to m_initialDir.
     if ( !m_initialDir.empty() )
         DoSetInitialDirectory(dialog, m_initialDir);
 
+    // This sets both the default file name and the default directory of the
+    // dialog if m_path contains directory part.
+    dialog->SetPath(m_path);
+
     return dialog;
 }