How to highlight lines with color one by one?

Heart Strong

like zebra?

Alan Kilborn

So really what you are asking is how to make every other line stand out in some way, I would guess so that when your eyes are tracking far away from the line number area, that you can tell which line is which?

You can’t do this with Notepad++ as it ships, but you can do it with a scripting plugin. Here’s an example using the LuaScript plugin: https://dail8859.github.io/LuaScript/examples/stylecsv.lua.html

Alan Kilborn

As an alternative method, here’s how to do it with the PythonScript plugin. I call this script BackgroundColorEveryOtherLine.py.

# -*- coding: utf-8 -*-
from __future__ import print_function

from Npp import *

class BCEOL(object):

    def __init__(self):
        self.indicator_nbr = 20
        editor.indicSetStyle(self.indicator_nbr, INDICATORSTYLE.FULLBOX)
        editor.indicSetFore(self.indicator_nbr, (0xB5, 0xB5, 0xB5))
        editor.indicSetAlpha(self.indicator_nbr, 100)
        editor.indicSetOutlineAlpha(self.indicator_nbr, editor.indicGetAlpha(self.indicator_nbr))
        editor.indicSetUnder(self.indicator_nbr, True)
        editor.callbackSync(self.updateui_callback, [SCINTILLANOTIFICATION.UPDATEUI])
        self.updateui_callback(None)

    def getLastVisibleLine(self):  # companion to editor.getFirstVisibleLine()
        first_line = editor.getFirstVisibleLine()
        last_visible_line = first_line + editor.linesOnScreen()
        if 1: # deal with the case where (e.g.) viewport is 40 lines but file has only 10 lines of content
            last_real_line = editor.lineFromPosition(editor.getTextLength())
            if last_real_line < last_visible_line: last_visible_line = last_real_line
        return last_visible_line

    def clear_ind_from_start_to_end(self, start_pos, end_pos):
        editor.setIndicatorCurrent(self.indicator_nbr)
        editor.indicatorClearRange(start_pos, end_pos - start_pos)

    def fill_ind_from_start_to_end(self, start_pos, end_pos):
        editor.setIndicatorCurrent(self.indicator_nbr)
        editor.indicatorFillRange(start_pos, end_pos - start_pos)

    def updateui_callback(self, args):
        for line_nbr in range(editor.getFirstVisibleLine(), self.getLastVisibleLine() + 1):
            line_start_pos = editor.positionFromLine(line_nbr)
            line_end_pos = editor.getLineEndPosition(line_nbr)
            self.clear_ind_from_start_to_end(line_start_pos, line_end_pos)
            if line_nbr % 2:  # color every other line
                self.fill_ind_from_start_to_end(line_start_pos, line_end_pos)

if __name__ == '__main__': BCEOL()

Here’s a bit of the effect:

dail

@alan-kilborn That’s pretty neat. Another option might be to look at markers. SC_MARK_BACKGROUND would give a nice affect since it colors the entire line, not just the text. Though maybe it is easier to manage indicators on each UI update rather than markers.

Alan Kilborn

So I took @dail’s suggestion to heart and made a new version of the script that uses markers. I must say that with the coloring extending past the ends of the lines, it is a better effect. Here’s BackgroundColorEveryOtherLine2.py:

# -*- coding: utf-8 -*-
from __future__ import print_function

from Npp import *

#-------------------------------------------------------------------------------

def editor_getLastVisibleLine():  # companion to editor.getFirstVisibleLine()
    first_line = editor.getFirstVisibleLine()
    last_visible_line = first_line + editor.linesOnScreen()
    if 1: # deal with the case where (e.g.) viewport is 40 lines but file has only 10 lines of content
        last_real_line = editor.lineFromPosition(editor.getTextLength())
        if last_real_line < last_visible_line: last_visible_line = last_real_line
    return last_visible_line

def editor_indicClearFromPosToPos(indicator_nbr, start_pos, end_pos):
    # need to do these statements in as quick succession as possible, so that N++ itself doesn't interfere
    editor.setIndicatorCurrent(indicator_nbr)
    editor.indicatorClearRange(start_pos, end_pos - start_pos)

def editor_indicFillFromPosToPos(indicator_nbr, start_pos, end_pos):
    # need to do these statements in as quick succession as possible, so that N++ itself doesn't interfere
    editor.setIndicatorCurrent(indicator_nbr)
    editor.indicatorFillRange(start_pos, end_pos - start_pos)

#-------------------------------------------------------------------------------

class BCEOL_with_indicators(object):

    def __init__(self):
        self.indicator_nbr = 20
        editor.indicSetStyle(self.indicator_nbr, INDICATORSTYLE.FULLBOX)
        editor.indicSetFore(self.indicator_nbr, (0xB5, 0xB5, 0xB5))
        editor.indicSetAlpha(self.indicator_nbr, 100)
        editor.indicSetOutlineAlpha(self.indicator_nbr, editor.indicGetAlpha(self.indicator_nbr))
        editor.indicSetUnder(self.indicator_nbr, True)
        editor.callbackSync(self.updateui_callback, [SCINTILLANOTIFICATION.UPDATEUI])
        self.updateui_callback(None)

    def updateui_callback(self, args):
        for line_nbr in range(editor.getFirstVisibleLine(), editor_getLastVisibleLine() + 1):
            line_start_pos = editor.positionFromLine(line_nbr)
            line_end_pos = editor.getLineEndPosition(line_nbr)
            editor_indicClearFromPosToPos(self.indicator_nbr, line_start_pos, line_end_pos)
            if line_nbr % 2:  # color every other line
                editor_indicFillFromPosToPos(self.indicator_nbr, line_start_pos, line_end_pos)

#-------------------------------------------------------------------------------

class BCEOL_with_markers(object):

    def __init__(self):

        self.marker_id = 0
        marker_symbol = MARKERSYMBOL.BACKGROUND
        editor.markerDefine(self.marker_id, marker_symbol)
        editor.markerSetBack(self.marker_id, (0xB5, 0xB5, 0xB5))
        editor.callbackSync(self.updateui_callback, [SCINTILLANOTIFICATION.UPDATEUI])
        self.updateui_callback(None)

    def updateui_callback(self, args):
        for line_nbr in range(editor.getFirstVisibleLine(), editor_getLastVisibleLine() + 1):
            marker_mask = editor.markerGet(line_nbr)
            has_marker_already = True if (marker_mask & (1 << self.marker_id)) else False
            if line_nbr % 2:
                if not has_marker_already: editor.markerAdd(line_nbr, self.marker_id)
            else:
                if has_marker_already: editor.markerDelete(line_nbr, self.marker_id)

#-------------------------------------------------------------------------------

if __name__ == '__main__':
    #BCEOL_with_indicators()
    BCEOL_with_markers()

Here’s a sample of its appearance:

Alan Kilborn

So the above is really just a “demo”, but, as sometimes happens here, after writing a demo, I find a real use for it.

When that happened this time, I noticed that if the script is run while a “view 0” tab is active, it won’t cause the every-other-line shading to happen for a tab in “view 1”.

This can be avoided by changing the script code to influence both editor1 and editor2.

For the marker-based coloring, the marker init code could be changed to:

for e in (editor1, editor2):
    e.markerDefine(self.marker_id, marker_symbol)
    e.markerSetBack(self.marker_id, (0xB5, 0xB5, 0xB5))

For the indicator-based coloring, the indicator init code could be changed to:

for e in (editor1, editor2):
    e.indicSetStyle(self.indicator_nbr, INDICATORSTYLE.FULLBOX)
    e.indicSetFore(self.indicator_nbr, (0xB5, 0xB5, 0xB5))
    e.indicSetAlpha(self.indicator_nbr, 100)
    e.indicSetOutlineAlpha(self.indicator_nbr, e.indicGetAlpha(self.indicator_nbr))
    e.indicSetUnder(self.indicator_nbr, True)

–
edit: fixed indicator vs marker to make descriptions match code snippets

Alan Kilborn

So I noticed some weirdness with this script, specifically, when using it with the ChangedLines plugin, and I do a column insert of data, I expect ChangedLines to color each changed line orange (my set color for unsaved modifications), but I see this instead:

The orange is there but only on lines not having a marker set by the code above. I thought maybe the plugin’s code and my code were using the same marker id, but I changed from using 0 to using 7 and the problem persisted. My thinking here was that even if the plugin uses a few marker ids, and 0 is seemingly used, it wouldn’t use eight marker ids and 7 would be available.

Notepad++ source says that 0 - 15 are available for plugins.

I think I’ve coded my script to use markers in the right way.

I was wondering if @dail or @michael-vincent could shed some light here?

Michael Vincent

@alan-kilborn said in How to highlight lines with color one by one?:

I was wondering if @dail or @michael-vincent could shed some light here?

Changed Lines uses markers 10 (changes) and 11 (saves). I don’t think I leave that customizable - you can change the marker “type”, but not the ID. Markers I think are cumulative, that is the marker is basically a 32-bit binary number where I’m flipping bits 10 and 11 for ChangedLines and you’re flipping bit 0 or 7 (if I read your post correctly). The markers aren’t supposed to interfere with each other - seems you’re using SC_MARK_FULLRECT for ChangedLines and SC_MARK_BACKGROUND for your script.

Cheers.

Alan Kilborn

@michael-vincent said in How to highlight lines with color one by one?:

if I read your post correctly

I believe you did.

So what you’ve said and what I know indicates there should be no interference. Hmmm…

Maybe @dail will have some insight. Thanks for yours.

Free marker (and indicator) allocation could be handled better by N++. It seems like there should be a “pool” and N++ could hand them out when a plugin (or script) says “gimme a free one”. Maybe that’s asking too much.

seems you’re using SC_MARK_FULLRECT for ChangedLines and SC_MARK_BACKGROUND for your script.

And this wouldn’t be a point of possible interference anyway. The interference would be in reusing a marker id number, not how that marker manifests visually on screen.

Michael Vincent

@alan-kilborn said in How to highlight lines with color one by one?:

And this wouldn’t be a point of possible interference anyway. The interference would be in reusing a marker id number, not how that marker manifests visually on screen.

Agree, but I allow changing a marker type in Changed Lines and if both were trying to use line background coloring, I’m not sure what would happen - a combination of both colors? Last one to execute wins? In any case, you’re right - different visuals so visual interference is not the answer in this case.

Cheers.

dail

@Alan-Kilborn My only suggestion would be maybe look at SCI_SETMARGINMASKN to see if changing what margins the markers are applied to can make a difference.

Alan Kilborn

@dail

I tried some experimentation with that but I didn’t get a change in effect. My original use of marker 0 showed that it wasn’t assigned to any margin. I tried assigning it to some of the margins using the command you cited, but again it didn’t make a difference. Of course when the effect is seen visually NOT in any true margin, it is kind of hard to understand how it works.

Regardless, the slight downside of not being able to see change indications for lines that will be background-colored by my script is acceptable.