如何使用JTable的行分类器恢复原始行顺序？

Question

I've enabled sorting in JTable with setAutoCreateRowSorter method. Mouse clicks on the column headers will switch between ascending and descending order, but I would like to switch it between ascending, descending and the original (unsorted) row order. Any hints how to achieve this?

Answer 1

The mapping of a mouse click to changing the sort state is implemented in BasicTableHeaderUI and happens exclusively via the RowSorter's toggleSortOrder(columnIndex). It's default behaviour is to switch

UNSORTED --> ASCENDING --> DESCENDING --> ASCENDING --

that is, no way back into the UNSORTED. If the requirement is to simply widen the circle into:

UNSORTED --> ASCENDING --> DESCENDING -- UNSORTED --> ASCENDING --

the way to go is to subclass TableRowSorter and override its toggleSortOrder accordingly

    /** 
     * @inherited <p>
     */
    @Override
    public void toggleSortOrder(int column) {
        List<? extends SortKey> sortKeys = getSortKeys();
        if (sortKeys.size() > 0) {
            if (sortKeys.get(0).getSortOrder() == SortOrder.DESCENDING) {
                setSortKeys(null);
                return;
            }
        }
        super.toggleSortOrder(column);
    }

Note: this is a bit simplified as it doesn't account for n-ary sorted columns, see SwingX DefaultSortController for a full version. Or use SwingX to start with, its JXTable has api to configure the sorting cycle like

 table.setSortOrderCycle(ASCENDING, DESCENDING, UNSORTED);

Cheers Jeanette

Answer 2

This code implements cycle ASCENDING->DESCENDING->UNSORTED->... without overriding TableRowSorter:

TableRowSorter sorter = new TableRowSorter(getModel());
setRowSorter(sorter);
// Remove default sort MouseListener
for (MouseListener mouseListener : getTableHeader().getMouseListeners()) {
    if (mouseListener instanceof javax.swing.plaf.basic.BasicTableHeaderUI.MouseInputHandler) {
        getTableHeader().removeMouseListener(mouseListener);
    }
}
// Add MouseListener for onClick event
getTableHeader().addMouseListener(new MouseAdapter() {
    private SortOrder currentOrder = SortOrder.UNSORTED;

    @Override
    public void mouseClicked(MouseEvent e) {
        int column = getTableHeader().columnAtPoint(e.getPoint());
        RowSorter sorter = getRowSorter();
        List sortKeys = new ArrayList();
        switch (currentOrder) {
            case UNSORTED:
                sortKeys.add(new RowSorter.SortKey(column, currentOrder = SortOrder.ASCENDING));
                break;
            case ASCENDING:
                sortKeys.add(new RowSorter.SortKey(column, currentOrder = SortOrder.DESCENDING));
                break;
            case DESCENDING:
                sortKeys.add(new RowSorter.SortKey(column, currentOrder = SortOrder.UNSORTED));
                break;
        }
        sorter.setSortKeys(sortKeys);
    }
});

Answer 3

If you're using the DefaultRowSorter : "An empty sortKeys list indicates that the view should [be] unsorted, the same as the model."

RowSorter rs = table.getRowSorter();
rs.setSortKeys(null);

Addendum: Note that " null is a shorthand for specifying an empty list" in setSortKeys() .

Answer 4

Kornell's answer is working great for me (thanks!)

I made these changes which others may find helpful:

1. Convert column from view to model coordinates. This is a bug in the original.
2. Omit removing the other mouse listeners, because doing this disables column dragging and resizing.
3. Filter out anything but left clicks

4. Whenever column changes, reinitialize sort order. User experience is significantly more intuitive this way, as you can successively click different columns and get ascending order each time.

    TableRowSorter sorter = new TableRowSorter(getModel()); setRowSorter(sorter); getTableHeader().addMouseListener(new MouseAdapter() { private SortOrder currentOrder = SortOrder.UNSORTED; private int lastCol = -1; @Override public void mouseClicked(MouseEvent e) { int column = getTableHeader().columnAtPoint(e.getPoint()); column = convertColumnIndexToModel(column); if (column != lastCol) { currentOrder = SortOrder.UNSORTED; lastCol = column; } RowSorter<?> sorter = getRowSorter(); List<SortKey> sortKeys = new ArrayList<SortKey>(); if (e.getButton() == MouseEvent.BUTTON1) { switch (currentOrder) { case UNSORTED: sortKeys.add(new RowSorter.SortKey(column, currentOrder = SortOrder.ASCENDING)); break; case ASCENDING: sortKeys.add(new RowSorter.SortKey(column, currentOrder = SortOrder.DESCENDING)); break; case DESCENDING: sortKeys.add(new RowSorter.SortKey(column, currentOrder = SortOrder.UNSORTED)); break; } sorter.setSortKeys(sortKeys); } } }); 

Answer 5

由于内置排序机制仅为您提供升序或降序，如果您在JTable附近提供外部重载JButton，您可以返回到原始状态，只需将相同的模型设置回您显示的模型在任何排序活动发生之前，表格是第一次。

Answer 6

If you looking for UI way of doing it - shift-click on column header will do it. This is built-in JTable functionality