Move line numbers in arabic pane to right of screen

[sgrieve]

This may require modifying the TextLineNumber Java class.

[giordano]

I have looked into this, but it doesn't appear to be straightforward.

In the line-numbers-arabic branch you can find my attempt at addressing this issue. I made some minor adjustments to the Java class in order to be able to customise appearance of the line numbers panel depending on whether it's for a left-to-right or right-to-left text component.

The main problem is that the TextLineNumber class heavily relies on being attached to the text component with setRowHeader. In standard Java Swing there is no setRowFooter (note: there is in Jide: http://www.jidesoft.com/javadoc/com/jidesoft/swing/JideScrollPane.html). With @raquel-ucl, we tried attaching the line numbers to the panel in AtfAreaView.__init__ with:

        pref_size = Dimension(1, 500)
        self.edit_area.setPreferredSize(pref_size)
        self.container = JScrollPane(self.edit_area)
        outer_container = JPanel()
        outer_container.setLayout(BorderLayout())
        outer_container.add(self.container, BorderLayout.CENTER)
        outer_container.add(self.line_numbers_area, BorderLayout.EAST)
        outer_container.setPreferredSize(pref_size)
        self.add(outer_container, BorderLayout.CENTER)

In this way, TextLineNumber.paintComponent miscomputes clip = g.getClipBounds(), because g never changes. I tried setting clip = component.getVisibleRect(), but doesn't fully work and scrolling the text doesn't update the line numbers (probably because repainting is not triggered, as the text scrollbar now is somewhat separated from the line numbers).

I'll leave the branch here for reference in case anyone will want to have a look in the future.

[ageorgou]

According to this answer, switching the orientation of the JScrollPane that contains the numbers and the edit area should work. At the moment we're setting the orientation of the whole text pane (arabic_area), but not the scroll pane (secondary_editor), so maybe it's not "inherited" (or it's set after we create the scroll pane)?

Looking at it more, the JScrollPane's setComponentOrientation method does something beyond the default, so we probably need to invoke it, whereas for the JTextPane it's related to the text direction. Changing the orientiation of the scroll pane will also move the scroll bar to the left, but I guess that may be reasonable?

[giordano]

Changing the orientiation of the scroll pane will also move the scroll bar to the left, but I guess that may be reasonable?

I'm not familiar, but googling for Arabic text editors it seems that some of them do have scroll bar to the left, but not all.

[ageorgou]

Another (untested!) possible solution, with a variant of the TextLineNumber: https://stackoverflow.com/a/52326451/11658609

[giordano]

Well, it turned out that simply setting the orientation of the container of the Arabic line numbers to right-to-left was sufficient. I'm going to open a pull request