Resolves: tdf#153059 after ChangeHeaderOrFooter the control can be disposed

If the cursor is still on page one then when a header, via a control on
another page, is added it jumps back to that page, so the widget on the
now hidden page is removed, but the click handler hasn't completed so
the follow up action to change it from a "plus" button to a dropdown
menubutton was on a disposed widget.

Change-Id: I981126412a0ee6a667d77fb97a3db2f2b0a0363c
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/145586
Reviewed-by: Xisco Fauli <xiscofauli@libreoffice.org>
Reviewed-by: Michael Stahl <michael.stahl@allotropia.de>
Tested-by: Caolán McNamara <caolanm@redhat.com>
Reviewed-by: Caolán McNamara <caolanm@redhat.com>

1 files changed, 7 insertions, 2 deletions

diff --git a/sw/source/uibase/docvw/HeaderFooterWin.cxx b/sw/source/uibase/docvw/HeaderFooterWin.cxx
index 0e79e1481012..539a310b08aa 100644
--- a/sw/source/uibase/docvw/HeaderFooterWin.cxx
+++ b/sw/source/uibase/docvw/HeaderFooterWin.cxx
@@ -549,8 +549,13 @@ IMPL_LINK_NOARG(SwHeaderFooterWin, ClickHdl, weld::Button&, void)
 
     const SwPageFrame* pPageFrame = SwFrameMenuButtonBase::GetPageFrame(m_pFrame);
     const OUString& rStyleName = pPageFrame->GetPageDesc()->GetName();
-    rSh.ChangeHeaderOrFooter( rStyleName, m_bIsHeader, true, false );
-
+    {
+        VclPtr<SwHeaderFooterWin> xThis(this);
+        rSh.ChangeHeaderOrFooter( rStyleName, m_bIsHeader, true, false );
+        //tdf#153059 after ChangeHeaderOrFooter is it possible that "this" is disposed
+        if (xThis->isDisposed())
+            return;
+    }
     m_xPushButton->hide();
     m_xMenuButton->show();
     PaintButton();