[🐛 BUG] Multi-value slider with lov binds value to the post-adapter lov elements

[arcanaxion]

What went wrong? 🤔

Example code:

from taipy.gui import Gui
import taipy.gui.builder as tgb

aggregation_list = ["minute", "hour", "day", "week"]
selected_aggregation = [aggregation_list[0], aggregation_list[1]]

def aggregation_adapter(aggregation):
    return aggregation.title()

with tgb.Page() as page:
    tgb.text("# Adapter modifying bound value for multi-value slider", mode="md")
    tgb.slider("{selected_aggregation}", lov="{aggregation_list}", label="Aggregation", adapter=aggregation_adapter)
    tgb.text("{selected_aggregation}")

def on_change(state, var_name, var_value):
    print(var_name, type(var_value), var_value)

if __name__ == "__main__":
    gui = Gui(page=page)
    gui.run()

In develop, modifying the slider displays:

Seems to be a regression -- was working as expected in 4.0.1.

Expected Behavior

Values should be lowercase

Browsers

Chrome, Firefox

OS

Windows, Linux

Version of Taipy

develop

Acceptance Criteria

• A unit test reproducing the bug is added.
• Any new code is covered by a unit tested.
• Check code coverage is at least 90%.
• The bug reporter validated the fix.
• Related issue(s) in taipy-doc are created for documentation and Release Notes are updated.

Code of Conduct

• I have checked the existing issues.
• I am willing to work on this issue (optional)

[FredLL-Avaiga]

Does it work for single value selection ?

[FredLL-Avaiga]

If you want an id different from your label, you need to specify it in your adapter:

def aggregation_adapter(aggregation):
    return (aggregation, aggregation.title())

Does that work for you @arcanaxion ?

import taipy.gui.builder as tgb
from taipy.gui import Gui

aggregation_list = ["minute", "hour", "day", "week"]
selected_aggregation = [aggregation_list[0], aggregation_list[1]]

def aggregation_adapter(aggregation):
    return (aggregation, aggregation.title())

with tgb.Page() as page:
    tgb.text("# Adapter modifying bound value for multi-value slider", mode="md")
    tgb.slider("{selected_aggregation}", lov="{aggregation_list}", label="Aggregation", adapter=aggregation_adapter)
    tgb.text("{selected_aggregation}")

def on_change(state, var_name, var_value):
    print(var_name, type(var_value), var_value)

if __name__ == "__main__":
    gui = Gui(page=page)
    gui.run(title="2290 [🐛 BUG] Multi-value slider with lov binds value to the post-adapter lov elements")

[arcanaxion]

@FredLL-Avaiga Yes, your correction works for me and it makes sense. Indeed the docs state that adapter should return a tuple.

But the inconsistency using my (wrong) method only seems to be affecting multi-value sliders:

from taipy.gui import Gui
import taipy.gui.builder as tgb

aggregation_list = ["minute", "hour", "day", "week"]
selected_aggregation_multiple = [aggregation_list[0], aggregation_list[1]]
selected_aggregation = aggregation_list[0]
selected_aggregation_selector = aggregation_list[0]

def aggregation_adapter(aggregation):
    return aggregation.title()

with tgb.Page() as page:
    tgb.text("# Adapter modifying bound value for multi-value slider", mode="md")
    tgb.slider("{selected_aggregation_multiple}", lov="{aggregation_list}", adapter=aggregation_adapter)
    tgb.text("{selected_aggregation_multiple}")

    tgb.slider("{selected_aggregation}", lov="{aggregation_list}", adapter=aggregation_adapter)
    tgb.text("{selected_aggregation}")

    tgb.selector("{selected_aggregation_selector}", lov="{aggregation_list}", adapter=aggregation_adapter)
    tgb.text("{selected_aggregation_selector}")

def on_change(state, var_name, var_value):
    print(var_name, type(var_value), var_value)

if __name__ == "__main__":
    gui = Gui(page=page)
    gui.run()

Probably this should either work consistently, or perhaps raise an error if the adapter is not returning a 2-element tuple.

[FredLL-Avaiga]

@FabienLelaquais Doc ?

[arcanaxion]

@FredLL-Avaiga I think the issue I'm having is unrelated to adapters.

I'm comparing 3 versions:

1. 3.0.1 (I'm updating an old application using this version)
2. 4.0.1 (latest stable release)
3. develop (because I want the fix in add current scope variables when evaluating an expression #2250)

Problem with tree

First I noticed that the "tree" element was returning ids instead of lov elements. Example copied from the docs:

from taipy.gui import Gui, State, Markdown
from typing import Any

users = [
    {"id": "231", "label": "Johanna", "year": 1987, "children": [{"id": "231.1", "label": "Johanna's son", "year": 2006}]},
    {"id": "125", "label": "John",    "year": 1979, "children": []},
    {"id": "4",   "label": "Peter",   "year": 1968, "children": []},
    {"id": "31",  "label": "Mary",    "year": 1974, "children": []}
    ]

user_sel = users[2]

page = Markdown(
"""
# Trees

<|{user_sel}|tree|lov={users}|>

""")

def on_change(state: State, var_name: str, var_value: Any):
    print(var_name, type(var_value), var_value)

if __name__ == "__main__":
    gui = Gui(page=page)
    gui.run(run_browser=False)

When I click on John:
- 3.0.1 and 4.0.1 would have var_value: [{'id': '125', 'label': 'John', 'year': 1979, 'children': []}]
- develop would have var_value: ['125']

Setting not value_by_id did not change anything, and that is already the default according to the docs.

This made me look at the example in this github issue again.

Slider, without adapter

See the following. I'm not using tgb because the tgb.selector didn't seem to work for me in 3.0.1:

from taipy.gui import Gui
import taipy.gui.builder as tgb


aggregation_list = [("minute", "Minute"), ("hour", "Hour"), ("day", "Day"), ("week", "Week")]
selected_aggregation_slider_multiple = [aggregation_list[0], aggregation_list[1]]
selected_aggregation_slider_single = None
selected_aggregation_selector_single = aggregation_list[0]

page = Markdown(
"""
# No adapter

<|{selected_aggregation_slider_multiple}|slider|lov={aggregation_list}|>

<|{repr(selected_aggregation_slider_multiple)}|>

<|{selected_aggregation_slider_single}|slider|lov={aggregation_list}|>

<|{repr(selected_aggregation_slider_single)}|>

<|{selected_aggregation_selector_single}|selector|lov={aggregation_list}|>

<|{repr(selected_aggregation_selector_single)}|>

""")

def on_change(state, var_name, var_value):
    print(var_name, type(var_value), var_value)


if __name__ == "__main__":
    gui = Gui(page=page)
    gui.run(run_browser=False, use_reloader=True)

3.0.1

This has the most expected behaviour to me:

3.0.1.slider.mp4

All 3 visual elements are giving the selected lov element (a tuple) as its value.

4.0.1

Here, a possibly unrelated issue, the single value slider becomes strange:

4.0.1.slider.mp4

I'm expecting a single value slider but it's becoming a multi-value slider.

develop

Here we start seeing what I think this github issue is related to:

develop.slider.mp4

The multi-value has renders the expected initial state. After interaction, the multi-value slider starts giving ids instead of lov elements, even though value_by_id is not set.

The unexpected behaviour for single value slider is also still present.

For all 3 versions, the selector has the same expected behaviour.

If this is actually just yet-to-be-documented behaviour for a future release, please let me know and I will go back to stable 😅

[FredLL-Avaiga]

I'll look into it
thanks for the detailed report @arcanaxion

[FredLL-Avaiga]

There was indeed a bug in the way we handle multiple selection in lov based components