JTable Scrolling to a Specified Row Index

I have a JTable that is within a JScrollPane. Rows are added to the table at runtime based on events that happen in my application. I want to have the scoll pane scroll to the bottom of the table when a new row is added to the table.

For JLists There is the [ensureIndexIsVisible][1]() that forces a particular index in the list to be visible. I'm looking for the same thing but for a JTable. It looks like I might have to manually move the scrolling view on the scroll pane but I figured there had to be an easier way.

It's very easy, JTable has scrollRectToVisible method too. If you want, you can try something like this to make scrollpane go to to the bottom if a new record is added :

jTable1.getSelectionModel().setSelectionInterval(i, i);
jTable1.scrollRectToVisible(new Rectangle(jTable1.getCellRect(i, 0, true)));

Where i is last added record.

See this example : http://www.exampledepot.com/egs/javax.swing.table/Vis.html

update: the link is now obsolete, here is the code (from http://smi-protege.stanford.edu/repos/protege/protege-core/trunk/src/edu/stanford/smi/protege/util/ComponentUtilities.java )

public static void scrollToVisible(JTable table, int rowIndex, int vColIndex) {
        if (!(table.getParent() instanceof JViewport)) {
            return;
        }
        JViewport viewport = (JViewport)table.getParent();

        // This rectangle is relative to the table where the
        // northwest corner of cell (0,0) is always (0,0).
        Rectangle rect = table.getCellRect(rowIndex, vColIndex, true);

        // The location of the viewport relative to the table
        Point pt = viewport.getViewPosition();

        // Translate the cell location so that it is relative
        // to the view, assuming the northwest corner of the
        // view is (0,0)
        rect.setLocation(rect.x-pt.x, rect.y-pt.y);

        table.scrollRectToVisible(rect);

        // Scroll the area into view
        //viewport.scrollRectToVisible(rect);
    }

JList internally use scrollRectToVisible and specify the coordinates to scroll to. I think you will have to recode a similar functionality for JTable.

The first answer works well, but the selected row gets positioned at the bottom of the table. So I created this modified version:

private void scrollToVisible(int rowIndex, int vColIndex ) {
        JTable table = getTablePanel().getTable();
        if (!(table.getParent() instanceof JViewport)) {
            return;
        }
        if (table.getRowCount()<1){
            return;
        }
        JViewport viewport = (JViewport)table.getParent();
        // view dimension
        Dimension dim = viewport.getExtentSize();
        // cell dimension
        Dimension dimOne = new Dimension(0,0);

        // This rectangle is relative to the table where the
        // northwest corner of cell (0,0) is always (0,0).
        Rectangle rect = table.getCellRect(rowIndex, vColIndex, true);
        Rectangle rectOne;
        if (rowIndex+1<table.getRowCount()) {
            if (vColIndex+1<table.getColumnCount())
                vColIndex++;
            rectOne = table.getCellRect(rowIndex+1, vColIndex, true);
            dimOne.width=rectOne.x-rect.x;
            dimOne.height=rectOne.y-rect.y;
        }

        // '+ veiw dimension - cell dimension' to set first selected row on the top

        rect.setLocation(rect.x+dim.width-dimOne.width, rect.y+dim.height-dimOne.height);

        table.scrollRectToVisible(rect);
    }

Now the selected row gets positioned at the top of the table.

It seems to me a lot easier to set the viewport position instead of scrolling the table. Following is my code.

public void scrollCellToView(int rowIndex, int vColIndex) {
    if (!(this.getParent() instanceof JViewport)) {
        return;
    }
    JViewport viewport = (JViewport) this.getParent();
    Rectangle rect = this.getCellRect(rowIndex, vColIndex, true);
    Rectangle viewRect = viewport.getViewRect();
    
    int x = viewRect.x;
    int y = viewRect.y;
    
    if (rect.x >= viewRect.x && rect.x <= (viewRect.x + viewRect.width - rect.width)){
        
    } else if (rect.x < viewRect.x){
        x = rect.x;
    } else if (rect.x > (viewRect.x + viewRect.width - rect.width)) {
        x = rect.x - viewRect.width + rect.width;
    }
    
    if (rect.y >= viewRect.y && rect.y <= (viewRect.y + viewRect.height - rect.height)){
        
    } else if (rect.y < viewRect.y){
        y = rect.y;
    } else if (rect.y > (viewRect.y + viewRect.height - rect.height)){
        y = rect.y - viewRect.height + rect.height;
    }
    
    viewport.setViewPosition(new Point(x,y));
}