tab not recognised in JList

[Ramu Eedupalli]

Hi,

I'm using a JList to display a string, but the string is separated by tabs into different fields. The JList doesnt recognise the tabs, and shows all the fields without spaces between them. To address this issue I used below code.

public class ComboBoxMultiColumn extends JFrame
{
	public ComboBoxMultiColumn()
	{
		String[] tabs = { "1\to\tn\te", "2\ttwo", "3\tth\tree", "4\tfour" };
		JList list = new JList( tabs );
		list.setCellRenderer( new TextPaneRenderer() );
		getContentPane().add( list );
	}

	public static void main(String[] args)
	{
		JFrame frame = new ComboBoxMultiColumn();
		frame.setDefaultCloseOperation( EXIT_ON_CLOSE );
		frame.pack();
		frame.setVisible( true );
	}

   	class TextPaneRenderer extends JTextPane implements ListCellRenderer
	{
		private final int TAB_COLUMN = 10;

		public TextPaneRenderer()
		{
			setMargin( new Insets(0, 0, 0, 0) );
                        
			FontMetrics fm = getFontMetrics( getFont() );
			int width = fm.charWidth( 'w' ) * TAB_COLUMN;

			TabStop[] tabs = new TabStop[1];
			tabs[0] = new TabStop( width, TabStop.ALIGN_LEFT, TabStop.LEAD_NONE );
       			TabSet tabSet = new TabSet(tabs);

			SimpleAttributeSet attributes = new SimpleAttributeSet();
			StyleConstants.setTabSet(attributes, tabSet);

			getStyledDocument().setParagraphAttributes(0, 0, attributes, false);
		}

		public Component getListCellRendererComponent(JList list, Object value,
			int index, boolean isSelected, boolean cellHasFocus)
		{
			setText( value.toString() );
			setBackground(isSelected ? list.getSelectionBackground() : null);
			setForeground(isSelected ? list.getSelectionForeground() : null);
			return this;
		}
	}
}

This code is working but the problem is if we have 3 tab characters in a single string only first tab character is getting replaced with the given width of tab stop other tab charecters are not getting replaced with the given width of tab stop.

[Michael Dunn]

> but the string is separated by tabs into different fields.

sounds like a JTable would suit better

[Ramu Eedupalli]

I want to have tab stop whereever there is a tab charecter in a string of JList

[Rob Camick]

if we have 3 tab characters in a single string only first tab character is getting replaced with the given width of tab stop other tab charecters are not getting replaced with the given width of tab stop.

Because you only set 1 tab stop. If you have 3 tabs then you need 3 tab stops.

[Ramu Eedupalli]

Can't we repeat single tab stop for multiple tabs?

[Rob Camick]

Ramu Eedupalli wrote:Can't we repeat single tab stop for multiple tabs?

Yes.

[Ramu Eedupalli]

How can we achieve this?

I tried like having multiple tabs of same width

TabStop[] tabs = new TabStop[2];   
tabs[0] = new TabStop( width, TabStop.ALIGN_LEFT, TabStop.LEAD_NONE );   
tabs[1] = new TabStop( width, TabStop.ALIGN_LEFT, TabStop.LEAD_NONE );   
TabSet tabSet = new TabSet(tabs); 

But still I am getting one tab stop only. I want to have only one tab stop and it should get repeated for multiple tabs.

If my string is "t\th\tr\te\te"
and if I define tab stop like this

TabStop[] tabs = new TabStop[1];   
tabs[0] = new TabStop( 10, TabStop.ALIGN_LEFT, TabStop.LEAD_NONE );   
TabSet tabSet = new TabSet(tabs); 

All \ts in the above string should get replaced with a blank space of width of 10 pixels.

[Rob Camick]

tabs[0] = new TabStop( width, TabStop.ALIGN_LEFT, TabStop.LEAD_NONE );      
tabs[1] = new TabStop( width * 2, TabStop.ALIGN_LEFT, TabStop.LEAD_NONE );