private void panelTabela_MouseUp(object sender, MouseEventArgs e)
        {
            if (e.Button != MouseButtons.Right)
            {
                return;
            }

            clickedItem = tabela.getItem(clientToTable(new PointF(e.X, e.Y)), selectedSprava(), selectedGrupa());
            if (clickedItem == null)
            {
                return;
            }

            bool showDodajElement         = true;
            bool showPromeniElement       = true;
            bool showPromeniVelicinuSlike = true;
            bool showBrisiElement         = true;
            bool showCut              = true;
            bool showPaste            = true;
            bool showIzaberiElement   = true;
            bool showIzaberiVarijantu = true;
            bool showSeparator1       = true;
            bool showSeparator2       = true;

            if (rezimRada == TabelaElemenataFormRezimRada.Select)
            {
                showDodajElement         = false;
                showPromeniElement       = false;
                showPromeniVelicinuSlike = false;
                showBrisiElement         = false;
                showCut            = false;
                showPaste          = false;
                showIzaberiElement = clickedItem.Element != null;

                if (clickedItem.Element != null &&
                    !clickedItem.Element.isVarijanta() &&
                    clickedItem.Element.Varijante.Count > 0)
                {
                    showIzaberiVarijantu = true;
                    mnIzaberiVarijantu.DropDownItems.Clear();
                    foreach (Element elem in clickedItem.Element.Varijante)
                    {
                        ToolStripMenuItem item =
                            new ToolStripMenuItem(elem.VarijantaString);
                        item.Tag     = elem;
                        item.Checked = izabrani.ContainsKey(elem.Id);
                        item.Click  += mnIzaberiVarijantu_Click;
                        mnIzaberiVarijantu.DropDownItems.Add(item);
                    }
                }
                else
                {
                    showIzaberiVarijantu = false;
                }
            }
            else
            {
                showIzaberiElement   = false;
                showIzaberiVarijantu = false;
                if (clickedItem.Element != null)
                {
                    showDodajElement         = false;
                    showPromeniElement       = true;
                    showPromeniVelicinuSlike = clickedItem.Element.Slike.Count > 0;
                    showBrisiElement         = true;
                    showCut   = true;
                    showPaste = false;
                }
                else
                {
                    showDodajElement         = true;
                    showPromeniElement       = false;
                    showPromeniVelicinuSlike = false;
                    showBrisiElement         = false;
                    showCut   = false;
                    showPaste = clipboard != null &&
                                clipboard.Sprava == clickedItem.Sprava;
                }
            }

            bool sector1Visible = showDodajElement || showPromeniElement ||
                                  showPromeniVelicinuSlike || showBrisiElement;
            bool sector2Visible = showCut || showPaste;
            bool sector3Visible = showIzaberiElement || showIzaberiVarijantu;

            showSeparator1 = sector1Visible && (sector2Visible || sector3Visible);
            showSeparator2 = sector3Visible && (sector1Visible || sector2Visible);
            if (showSeparator1 && showSeparator2 && !sector3Visible)
            {
                showSeparator2 = false;
            }

            mnDodajElement.Visible         = showDodajElement;
            mnPromeniElement.Visible       = showPromeniElement;
            mnPromeniVelicinuSlike.Visible = showPromeniVelicinuSlike;
            mnBrisiElement.Visible         = showBrisiElement;
            mnCut.Visible              = showCut;
            mnPaste.Visible            = showPaste;
            mnIzaberiElement.Visible   = showIzaberiElement;
            mnIzaberiVarijantu.Visible = showIzaberiVarijantu;
            mnSeparator1.Visible       = showSeparator1;
            mnSeparator2.Visible       = showSeparator2;

            Element element = null;

            if (clickedItem != null)
            {
                element = clickedItem.Element;
            }
            mnIzaberiElement.Checked = element != null &&
                                       izabrani.ContainsKey(element.Id);

            contextMenuTabela.Show(panelTabela, e.Location);
        }