Add stacked flag for MultiLineProgress, so that the bars stack instead of overwriting

[Archer6621]

My use case for the MultiLineProgress bar is one where I keep track of different results for the same process, e.g. succeeded versus failed, or perhaps even more. In this case, I always expect the same total amount of items, but each item might get a different label depending on the result. Currently, the progress lines all get written to index 0 on the main bar (useful for e.g. pipeline steps where each bar represents a step that all items have to go through), causing them to overwrite one another for this particular use case.

I'm proposing a flag stacked=True/False where when it is True, the control progress lines get stacked; each one writes where the previous line had ended. This way, when all items are processed and have received a label, the lines will fill the bar fully in the correct proportions.

Decided to go ahead and implement/PR it, since it is a very minor modification.

[Exahilosys]

To stack lines, simply nest the context managers!

import survey
import time

total = 1600

controls = [
    survey.graphics.MultiLineProgressControl(1600, color = survey.colors.basic('blue' ), epilogue = 'done!'),
    survey.graphics.MultiLineProgressControl(1600, color = survey.colors.basic('red'  )),
    survey.graphics.MultiLineProgressControl(1600, color = survey.colors.basic('green'), epilogue = lambda context: 'dynamic done!')
]

with survey.graphics.MultiLineProgress(controls) as l1:
    with survey.graphics.LineProgress(total = total) as l2:
        with survey.graphics.LineProgress(total = total, color = survey.colors.basic('magenta')) as l3:
            for _ in range(total):
                for index, control in enumerate(controls, start = 1):
                    if control.value >= total:
                        continue
                    for _ in range(index):
                        control.move(1)
                        time.sleep(0.01)
                if l2.controls[0].value >= total:
                    continue
                l2.move(1)
                l3.move(3)
                time.sleep(0.05)

I suppose the MultiLine part of the progress graphic's name might incline some to think these are indeed multiple lines, but they are actually one line with multiple controls - there is nothing to "stack" here alone🙂, you need multiple lines to have multiple... lines stacked on top of each other.

If this solves your issue feel free to close!

[Archer6621]

Ah, I meant stacking in the sense that each progress instance represents a portion of the total! So that they do not overlap, much like a bar in a stacked bar chart. But this approach that you showed also works for communicating the same thing.

I have switched to a slightly more elaborate way of showing progress using a different library, so this can be closed if nobody will use it.

[Exahilosys]

Oooh gocha, I'll consider adding it but yes for now this can be closed then :)

[Exahilosys]

Reopening because I didn't realize code was submitted to actually fix this issue (woops). I'll review and possibly merge!