UI artefact at bottom right corner of scrollpane

[Chrriis]

Hi,

I noticed a visual glitch when a component in a scrollpane is focused: the bottom corner at the intersection of the 2 scroll bars has an additional edge. Note that it is more or less visible depending on the theme you are using.

Here is a screenshot:

[DevCharly]

Is this from a HiDPI screen?

[Chrriis]

I wish I had a HiDPI screen! 😄

[Chrriis]

The artefact is the inner focus that gets painted in the scroll pane (0.5 is the default in the above). It is only visible in the bottom right corner because the other sides get painted over by the view and the 2 scroll bars.

If you try with a bigger inner focus width:

	public static void main(String[] args) throws Exception {
		UIManager.setLookAndFeel(new FlatLightLaf());
		UIManager.getDefaults().put("Component.innerFocusWidth", 2);
		JFrame frame = new JFrame();
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		JPanel centerPane = new JPanel(new BorderLayout());
		centerPane.setBorder(BorderFactory.createEmptyBorder(10, 10, 10, 10));
		JScrollPane scrollPane = new JScrollPane(new JTextArea(50, 80) {
			@Override
			public boolean hasFocus() {
				return true;
			}
		});
		centerPane.add(scrollPane);
		frame.getContentPane().add(centerPane);
		frame.setSize(400, 300);
		frame.setVisible(true);
	}

... you then clearly see it:

I think scroll panes should not paint the inner focus.

[DevCharly]

Many thanks.

The fix is now in master branch.

[Chrriis]

Thanks a lot, it works as advertised! 🙂