[Libreoffice-commits] core.git: vcl/qt5

[Jan-Marek Glogowski (via logerrit)]

 vcl/qt5/Qt5Clipboard.cxx |    9 +++++++++
 1 file changed, 9 insertions(+)

New commits:
commit 71471a36b125f6bdc915d5dbcae92ebcaa7ff5a4
Author:     Jan-Marek Glogowski <glogow at fbihome.de>
AuthorDate: Tue Apr 6 01:41:08 2021 +0200
Commit:     Jan-Marek Glogowski <glogow at fbihome.de>
CommitDate: Tue Apr 6 13:18:26 2021 +0200

    tdf#140404 Qt ignore "unchanged" clipboard events
    
    LO gets a Qt signal on all clipboard changes. For X11 you get one
    signal when you set the clipboard. Anything else normally signals
    lost of clipboard ownership.
    
    But on Wayland LO somehow gets a second notification without any
    actual change. AFAIK it's not triggered by any LO actions and
    isOwner still indicates, that LO has the ownership. This breaks
    the single notification assumption, the code was relying on.
    
    Initially I found it quite tricky to find a rule to identify the
    ignorable change signals.
    
    Change-Id: I744cdd3c4254533b01d909309ecc3967d789361e
    Reviewed-on: https://gerrit.libreoffice.org/c/core/+/113617
    Reviewed-by: Michael Weghorn <m.weghorn at posteo.de>
    Reviewed-by: Ilmari Lauhakangas <ilmari.lauhakangas at libreoffice.org>
    Reviewed-by: Jan-Marek Glogowski <glogow at fbihome.de>
    Tested-by: Jenkins

diff --git a/vcl/qt5/Qt5Clipboard.cxx b/vcl/qt5/Qt5Clipboard.cxx
index 8720cfe44310..41881f0be4b6 100644
--- a/vcl/qt5/Qt5Clipboard.cxx
+++ b/vcl/qt5/Qt5Clipboard.cxx
@@ -150,6 +150,15 @@ void Qt5Clipboard::handleChanged(QClipboard::Mode aMode)
 
     osl::ClearableMutexGuard aGuard(m_aMutex);
 
+    // QtWayland will send a second change notification (seemingly without any
+    // trigger). And any C'n'P operation in the Qt file picker emits a signal,
+    // with LO still holding the clipboard ownership, but internally having lost
+    // it. So ignore any signal, which still delivers the internal Qt5MimeData
+    // as the clipboard content and is no "advertised" change.
+    if (!m_bOwnClipboardChange && isOwner(aMode)
+        && dynamic_cast<const Qt5MimeData*>(QApplication::clipboard()->mimeData(aMode)))
+        return;
+
     css::uno::Reference<css::datatransfer::clipboard::XClipboardOwner> xOldOwner(m_aOwner);
     css::uno::Reference<css::datatransfer::XTransferable> xOldContents(m_aContents);
     // ownership change from LO POV is handled in setContents