Method commitHistorySnapshotIfNeeded

QKeyMapper/qmappingsequenceedit.cpp:409–439

}

void QMappingSequenceEdit::commitHistorySnapshotIfNeeded()
{
    if (m_IsRestoringHistory) {
        return;
    }

    const MappingSequenceHistorySnapshot snapshot = captureHistorySnapshot();

    // Skip empty steps: only record when the list content actually changes.
    if (m_HistoryIndex >= 0 && m_HistoryIndex < m_HistorySnapshots.size()) {
        if (m_HistorySnapshots.at(m_HistoryIndex).mappingSequenceList == snapshot.mappingSequenceList) {
            return;
        }
    }

    // If we have undone some steps, discard redo branch when a new change is committed.
    if (m_HistoryIndex >= 0 && m_HistoryIndex < m_HistorySnapshots.size() - 1) {
        m_HistorySnapshots.resize(m_HistoryIndex + 1);
    }

    m_HistorySnapshots.append(snapshot);
    m_HistoryIndex = m_HistorySnapshots.size() - 1;

    const int maxSnapshots = qMax(2, MAPPINGSEQUENCEEDIT_HISTORY_MAX + 1);
    while (m_HistorySnapshots.size() > maxSnapshots) {
        m_HistorySnapshots.remove(0);
        m_HistoryIndex = qMax(0, m_HistoryIndex - 1);
    }

    updateUndoRedoButtonsEnabled();
}

void QMappingSequenceEdit::undo()
{