fix: use a MutationObserver for heightByRows

[javier-godoy]

Close #163

Summary by CodeRabbit

• Bug Fixes

  • Enhanced the grid component's height adjustment mechanism to more reliably respond to content changes, ensuring proper layout rendering when data is dynamically added or removed.

• Chores

  • Updated copyright year to 2026.

_{✏️ Tip: You can customize this high-level summary in your review settings.}

[coderabbitai]

Walkthrough

The pull request updates the copyright year from 2024 to 2026 and refactors the height update mechanism in the grid helper connector from an event-based approach (listening to loading-changed events) to a MutationObserver-based approach that detects DOM mutations in the tbody element.

Changes

Cohort / File(s)	Summary
Grid Height Update Mechanism src/main/resources/META-INF/frontend/fcGridHelper/connector.js	Replaced loading-changed event listener with MutationObserver observing tbody#items for childList mutations; updated copyright year to 2026; refactored initialization to call _updateHeightByRows when DOM mutations occur rather than on grid-level events

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Possibly related PRs

• fix: compute heightByRows while loading #123: Modifies the same height-by-rows logic in connector.js, introducing or using _updateHeightByRows with different height update trigger mechanisms.

Suggested reviewers

• mlopezFC
• paodb

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and concisely describes the main change: replacing an event-based approach with a MutationObserver for the heightByRows feature.
Linked Issues check	✅ Passed	The PR addresses issue #163 by implementing a MutationObserver-based approach for heightByRows, which should resolve the integration test failure where expected value was 10 but observed was 9.
Out of Scope Changes check	✅ Passed	All changes are scoped to fixing the heightByRows behavior. Only copyright year bump and MutationObserver implementation in connector.js are present, both directly related to issue #163.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing touches

• 📝 Generate docstrings

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[coderabbitai]

Actionable comments posted: 1

Caution

Some comments are outside the diff and can’t be posted inline due to platform limitations.

⚠️ Outside diff range comments (1)

src/main/resources/META-INF/frontend/fcGridHelper/connector.js (1)

56-83: Consider adding explicit cleanup for observers.

Both the ResizeObserver and MutationObserver are created but never explicitly cleaned up when the grid is destroyed. If grids are dynamically added and removed in your application, these observers will prevent garbage collection, leading to memory leaks.

Consider adding a cleanup/destroy method to properly disconnect observers when the grid is no longer needed:

destroyHeightByRows: function() {
  if (grid.fcGridHelper._heightByRowsObserver) {
    grid.fcGridHelper._heightByRowsObserver.unobserve(grid);
    grid.fcGridHelper._heightByRowsObserver = null;
  }
  if (grid.fcGridHelper._heightByRowsMutationObserver) {
    grid.fcGridHelper._heightByRowsMutationObserver.disconnect();
    grid.fcGridHelper._heightByRowsMutationObserver = null;
  }
}

This method should be called when the grid is detached or destroyed.

🤖 Fix all issues with AI agents

In @src/main/resources/META-INF/frontend/fcGridHelper/connector.js:
- Around line 81-82: The code calls
grid.fcGridHelper._heightByRowsMutationObserver.observe(tbody, ...) without
ensuring tbody exists, which can throw if tbody is null; update the block around
the query selector for "tbody#items" to check that tbody is non-null before
calling grid.fcGridHelper._heightByRowsMutationObserver.observe, and if null
either skip observing (or log a warning) so observe is only called when tbody is
present.

🧹 Nitpick comments (1)

src/main/resources/META-INF/frontend/fcGridHelper/connector.js (1)

72-79: LGTM: Efficient mutation handling.

The MutationObserver correctly watches for childList mutations and efficiently breaks after processing the first one. The approach of updating height on DOM mutations should be more reliable than event-based detection.

If rapid mutations cause performance issues in the future, consider debouncing the _updateHeightByRows calls.

📜 Review details

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 961dbb1 and bbdb901.

📒 Files selected for processing (1)

• src/main/resources/META-INF/frontend/fcGridHelper/connector.js

🔇 Additional comments (1)

src/main/resources/META-INF/frontend/fcGridHelper/connector.js (1)

68-70: LGTM: Proper observer cleanup.

The code correctly disconnects any existing MutationObserver before creating a new one, preventing multiple observers from accumulating.