JTable cell alignment

[Mike Lipay]

Using the DefaultTableModel, is there a way to align the contents in a cell? I have the following data (dollar amount, column 6) that I would prefer be right-aligned in the cell.

// Service Table Model
private void PopulateTable()
{
	for ( int r = 0; r < serviceTable.length; r++ )
	{
		for ( int c = 0; c < serviceTable[r].length; c++ )
		{
			if (c == 0)	model.setValueAt(mf.format(serviceTable[r][c]), r, c);
			else if (c == 6) model.setValueAt(cf.format(serviceTable[r][c]), r, c);
			else model.setValueAt(serviceTable[r][c], r, c);
		}
	}
}


// Field formatting
	final DecimalFormat mf = new DecimalFormat ("000,000");
	final NumberFormat cf  = NumberFormat.getCurrencyInstance();


// Main panel fields
	private JPanel servicePanel	= new JPanel();


// Table values
	private Object[][] serviceTable = {
		{ 97300, "1/26/2009", "McElhinney's Service", 4798,
                       "Check alternator and oil pressure",
                       "Battery, Alternator, Serpentine Belt, Oil Pressure Sensor", 707.68},
		{ 0, "3/20/2008", "McElhinney's Service", 11112,
                       "Replace engine", "Motor, cables, fluids", 4534.61}
	};

	private JTable table;
	private DefaultTableModel model = new DefaultTableModel(columnNames, serviceTable.length);

[Mike Lipay]

Found my solution:

private DefaultTableModel model = new DefaultTableModel(columnNames, (serviceTable.length + 1))
{
	public Class<?> getColumnClass(int c)
	{
		if (c == 3)	return Integer.class;
		if (c == 6)	return Integer.class;
		return String.class;
	}
};

[Rob Camick]

I gave you an answer 3 weeks ago.

[Mike Lipay]

Rob, you did give me an answer when I was working with an AbstractTableModel, but when I switched to the DefaultTableModel it no longer worked. Maybe it was the way I implemented your suggestion, not sure. That is why I asked again for the DTM, sorry if it was inappropriate.

[Rob Spoor]

What do you mean, it no longer worked? It's exactly what you did to solve it! I quote from the other thread:

Rob Camick wrote:This is done by overriding the getColumnClass() method to return the proper class of data. So for dates, store a Date object in the model. For currency, store a Double object in the model. The table will choose the appropriate renderer and the renderer will choose the appropriate alignment.

[Mike Lipay]

I don't know, before the code was:

public Class<?> getColumnClass(int c)
	{
		if (c == clmnCost)	return Integer.class;
		return serviceTable[0][c].getClass();
	}

When I change it to DefaultTableModel from AbstractTableModel it didn't work. The second change was small, but (at the time of this post) I thought perhaps there was something different between Default and Abastract. The new code worked, maybe I made other changes that messed things up.

public Class<?> getColumnClass(int c)
{
	if (c == 3)	return Integer.class;
	if (c == 6)	return Integer.class;
	return String.class;
}

[Mike Lipay]

That's like another issue I'm having, and I've been real hesitant to post it. I searched for answers on how to capture a change in a cell, and all of the responses I've seen mention using setValueAt, no final code is posted and, in most cases, the thread just ends. Well, I tried that:

private DefaultTableModel model = new DefaultTableModel(columnNames, serviceTable.length)
{
	public void setValueAt(Object val, int row, int col)
	{
		System.out.println(val.toString());
	}
};

And, yes, I can capture the changes, but when the table initially displays all of its' contents are blank. Right number of rows and columns, but no data. Further searching showed suggesting adding

fireTableCellUpdated();

Well, that doesn't compile. Changing it to

fireTableCellUpdated(row, col);

compiles, but nothing is different. I figure others got it to work, but I'll be d--ned if I can figure out from the docs I've looked at on how it's done. Guess I'm just dumber than the others here, which makes me hesitant to even ask questions.

[Rob Camick]

maybe I made other changes that messed things up.

I'm sure I've asked you for a SSCCE before. This question is no different and this is one of the reasons why. We don't have time to guess what else you might have changed.

I searched for answers on how to capture a change in a cell,

Yes, well that question has nothing to do with this question. Keep a thread to one question otherwise it gets confusing with all the suggestions to multiple question in the same thread.

[Paul Clapham]

Mike Lipay wrote:That's like another issue I'm having, and I've been real hesitant to post it. I searched for answers on how to capture a change in a cell, and all of the responses I've seen mention using setValueAt, no final code is posted and, in most cases, the thread just ends. Well, I tried that:

private DefaultTableModel model = new DefaultTableModel(columnNames, serviceTable.length)
{
	public void setValueAt(Object val, int row, int col)
	{
		System.out.println(val.toString());
	}
};

And, yes, I can capture the changes, but when the table initially displays all of its' contents are blank. Right number of rows and columns, but no data.

What you did there was to override the setValueAt method to just throw away the parameters it was passed. What it should do is to update the model with that value in some way.

If I'm not mistaken, DefaultTableModel already has an implementation of setValueAt which updates the model data, so just removing that method entirely might be the best approach. But if you want to do something at the time that setValueAt is called, while still updating the model data, then just call super.setValueAt(val, row, col) inside your overridden method.

[Mike Lipay]

Paul, thanks, using the super. worked.