Semantic-Org/Semantic-UI-React

Dropdown: when options contain custom elements, setState in onChange leads to mismatch of 'active' and 'selected' option

Open

#2296 opened on Nov 6, 2017

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bughelp wantedstale

Description

Steps

I want to setState() within onChange of the Dropdown and have custom elements within the options like so:

const options = [ { value: "1",
                    content: <span>a</span> 
                              }, ... ];

Expected Result

  1. The selected option should be active and selected

  2. The state should be set and the dropdown should change its value. The content of the option <span>a</span> should appear in the dropdown.

Actual Result

  1. The state is set as expected. The selected option is set to active, the previously selected option is kept as selected. => Selected and active do not match the same option anymore

  2. The content does not appear in the dropdown

If text is used instead of content

  1. The selected option is set to active, the previously selected option is kept as selected. => Selected and active do not match the same option anymore

  2. The content does appear in the dropdown

Questions: What should I use, text or content for this case? How to solve the mismatch?

Version

0.76.0

Showcase https://codesandbox.io/s/pp0w7wrn7q

Partially solved here: https://github.com/Semantic-Org/Semantic-UI-React/pull/2252

Contributor guide

Tech stack
javascriptreact
Domain
frontend
Issue type
bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
stale
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
needs investigation
Prerequisites
basic React knowledgeunderstanding of Semantic UI React Dropdown
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
30
Research direction
Investigate the Dropdown component's handling of 'active' and 'selected' states when options contain custom React elements. The issue and referenced PR #2252 suggest a mismatch occurs when setState is called in onChange. Examine the source code in the Dropdown component, particularly the onChange handler and how selectedIndex and activeIndex are updated. Also review the sandbox provided in the issue to reproduce the bug. Consider whether using 'text' vs 'content' is recommended and ensure that custom elements are properly rendered in the dropdown trigger.