Last line is not displayed when scrolling using Display

[Arsou33]

Hi,

I'm using the artifact jline-terminal to build a user interface. ​In some conditions, the last line is not displayed

1 : ​ Display lines on every lines of the terminal :

 ----------- 
| Line 2    |
| Line 3    |
| Line 4    |
| Line 5    |
 ----------- 

2 : Display the same lines but all shift down with a first new lines

 ----------- 
| Line 1    |
| Line 2    |
| Line 3    |
|           | <-- Missing line not displayed
 ----------- 

Below a fonction to reproduce it. I tested it on iTerm2 and in a 'standard' terminal on MacOS.

    public static void main(String[] args) throws InterruptedException, IOException {

        try (Terminal terminal = TerminalBuilder.builder().build()) {
            Attributes savedAttributes = terminal.enterRawMode();
            terminal.puts(enter_ca_mode);
            int height = terminal.getHeight();

            Display display = new Display(terminal, true);
            display.resize(height, terminal.getWidth());

            // Build Strings to displayed
            List<AttributedString> lines1 = new ArrayList<>();
            for (int i = 1; i < height + 1; i++) {
                lines1.add( new AttributedString(String.format("%03d: %s", i, "Chaine de test...")));
            }

            List<AttributedString> lines2 = new ArrayList<>();
            for (int i = 0; i < height; i++) {
                lines2.add(new AttributedString(String.format("%03d: %s", i, "Chaine de test...")));
            }

             // Display with tempo 
            display.update(lines1, 0);
            Thread.sleep(3000);

            display.update(lines2, 0);
            Thread.sleep(3000);

            terminal.setAttributes(savedAttributes);
            terminal.puts(exit_ca_mode);
        }
    }

echo $TERM
xterm-256color

BR

[mattirn]

You can either clear the display (display.clear()) before displaying lines2 or add a common footer to your lines to be displayed:

            List<AttributedString> lines1 = new ArrayList<>();
            for (int i = 1; i < height; i++) {
                lines1.add( new AttributedString(String.format("%03d: %s", i, "Chaine de test...")));
            }
            lines1.add(new AttributedString(">>>"));

            List<AttributedString> lines2 = new ArrayList<>();
            for (int i = 0; i < height - 1; i++) {
                lines2.add(new AttributedString(String.format("%03d: %s", i, "Chaine de test...")));
            }
            lines2.add(new AttributedString(">>>"));

[Arsou33]

Thanks, i already added 'clear' as a workaround, and it's working.