RSyntaxTextArea not showing line numbers

Question

I'm using RSyntaxTextArea for a minimized IDE I'm working on, Everything seems to be really working smoothly except for the line numbering, which I couldn't really make it show:

                RSyntaxTextArea textArea = new RSyntaxTextArea(20, 60);
                textArea.setSyntaxEditingStyle(SyntaxConstants.SYNTAX_STYLE_C);
                textArea.setCodeFoldingEnabled(true);
                textArea.setAntiAliasingEnabled(true);
                RTextScrollPane sp = new RTextScrollPane(textArea);

                  sp.setLineNumbersEnabled(true);

                  sp.setFoldIndicatorEnabled(true);
                  if ( sp.getLineNumbersEnabled() )
                  {
                      System.out.println("Enabled"); // it prints the line but it's not showing 
                  }

                  contentPane.add(/*textEditorScrollPane*/ textArea, BorderLayout.CENTER);

I can't figure out why it's not showing the line numbers..

Answer 1

It's not showing the scrollbars either, right? Assuming that contentPane is where you want your components, you need to add the RTextScrollPane instance to the contentPane, not the RSyntaxTextArea instance. The Gutter, which displays line numbers, is a part of the RTextScrollPane - an extended JScrollPane.

If you don't add a scroll pane to your GUI, it will not be shown, nor will you be able to scroll around. :P

So try the following:

contentPane.add(sp, BorderLayout.CENTER);