Use key as main identity for st.slider and st.select_slider#12575
Merged
lukasmasuch merged 13 commits intodevelopfrom Oct 10, 2025
Merged
Use key as main identity for st.slider and st.select_slider#12575lukasmasuch merged 13 commits intodevelopfrom
key as main identity for st.slider and st.select_slider#12575lukasmasuch merged 13 commits intodevelopfrom
Conversation
Contributor
🎉 Snyk checks have passed. No issues have been found so far.✅ security/snyk check is complete. No issues have been found. (View Details) ✅ license/snyk check is complete. No issues have been found. (View Details) |
Contributor
✅ PR preview is ready!
|
Contributor
There was a problem hiding this comment.
Pull Request Overview
This PR modifies st.slider and st.select_slider widgets to use the provided key as the main identity when computing element IDs. This allows dynamic property changes without recreating widgets in the frontend, preserving state across reruns.
Key changes:
- Modified widget identity computation to use keys as main identity with whitelisted parameters
- Added comprehensive unit tests for stable ID behavior
- Added E2E tests demonstrating dynamic property updates while preserving widget state
Reviewed Changes
Copilot reviewed 8 out of 8 changed files in this pull request and generated 1 comment.
Show a summary per file
| File | Description |
|---|---|
| lib/streamlit/elements/widgets/slider.py | Updated element ID computation to use key as main identity with whitelisted parameters (min_value, max_value, step) |
| lib/streamlit/elements/widgets/select_slider.py | Updated element ID computation to use key as main identity with whitelisted parameters (options, format_func) |
| lib/tests/streamlit/elements/slider_test.py | Added unit tests for stable ID behavior with keys and whitelisted parameter changes |
| lib/tests/streamlit/elements/select_slider_test.py | Added unit tests for stable ID behavior with keys and whitelisted parameter changes |
| e2e_playwright/st_slider.py | Added test app for dynamic slider property updates |
| e2e_playwright/st_slider_test.py | Added E2E test verifying dynamic slider behavior |
| e2e_playwright/st_select_slider.py | Added test app for dynamic select slider property updates |
| e2e_playwright/st_select_slider_test.py | Added E2E test verifying dynamic select slider behavior |
sfc-gh-lmasuch
added
impact:internal
| dyn_val = st.select_slider( | ||
| "Initial dynamic select slider", | ||
| value="orange", | ||
| width="stretch", |
Collaborator
There was a problem hiding this comment.
[question] Why the change in width?
Collaborator
Author
There was a problem hiding this comment.
To test that you can dynamically change all (supported) parameters without resetting the component state. This was already working for width, but it doesn't hurt to ensure this in the tests.
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Describe your changes
If a custom
keyis passed to any of thest.sliderorst.select_sliderwidgets it will be used as the main identity. This allows for dynamically changing other parameters in between reruns without causing the widgets to be recreated in the frontend.GitHub Issue Link (if applicable)
Testing Plan
Contribution License Agreement
By submitting this pull request you agree that all contributions to this project are made under the Apache 2.0 license.