MudDataGrid: Add default and customizable ARIA semantics to select column

[versile2]

Overview

This PR improves accessibility for row selection in MudDataGrid by:

• Providing built-in, localized ARIA labels for select-all and row selection checkboxes.
• Allowing per-row ARIA label customization via the new AriaLabelFunc parameter on SelectColumn.
• Exposing aria-selected only for rows that participate in SelectColumn-based selection, and omitting it for disabled rows.

Key Changes

• Default ARIA Labels:
  • Row selection checkboxes use a localized "Select row" label by default.
  • Header/footer select-all checkboxes use a localized "Select all rows" label.
• Customizable Labels:
  • SelectColumn accepts AriaLabelFunc for custom per-row accessible names.
  • If AriaLabelFunc returns null/empty, the default label is used.
• Selection Semantics:
  • aria-selected is rendered only for selectable rows when a SelectColumn is present.
  • Disabled rows do not expose selection state.
• Documentation:
  • Docs updated to describe the new ARIA behavior and demonstrate AriaLabelFunc.
• Testing:
  • Unit tests added for default/custom labels, fallback logic, and aria-selected behavior.

Motivation

Previously, DataGrid selection checkboxes lacked accessible names and did not expose selection state, making them difficult to use with assistive technology. This PR ensures all selection controls are accessible by default and easily customizable.

Example Usage

<MudDataGrid T="Element" Items="@Elements.Take(10)" MultiSelection="true" SelectedItemsChanged="@SelectedItemsChanged">
    <Columns>
        <SelectColumn DisabledFunc="@(item => item.Number % 5 == 0)" AriaLabelFunc="@(item => $\"Select {item.Name}\")" />
        <PropertyColumn Property="x => x.Number" Title="Nr" />
        <PropertyColumn Property="x => x.Sign" />
        <PropertyColumn Property="x => x.Name" />
        <PropertyColumn Property="x => x.Position" />
        <PropertyColumn Property="x => x.Molar" Title="Molar mass" />
    </Columns>
</MudDataGrid>

Checklist

• Accessible ARIA labels for all selection checkboxes
• Customizable per-row ARIA labels
• aria-selected only for selectable rows
• Docs and tests updated

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This PR brings MudDataGrid selection controls up to modern accessibility standards while remaining easy to use and extend.

[Copilot]

Pull request overview

Adds built-in and customizable ARIA semantics for SelectColumn-based row selection in MudDataGrid, improving accessible naming for selection checkboxes and exposing selection state via aria-selected only when checkbox selection controls are present.

Changes:

• Added localized default labels for row and select-all selection checkboxes, plus AriaLabelFunc for per-row customization.
• Derived default row checkbox labels from visible value-bearing columns and disambiguated duplicates.
• Rendered aria-selected on data rows only when a SelectColumn is present and the row is selectable; expanded unit tests and updated docs.

Reviewed changes

Copilot reviewed 11 out of 11 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
src/MudBlazor/Resources/LanguageResource.resx	Adds new localization keys for “Select row” / “Select all rows”.
src/MudBlazor/Components/DataGrid/SelectColumn.razor.cs	Adds AriaLabelFunc + localizer-backed label resolution helpers.
src/MudBlazor/Components/DataGrid/SelectColumn.razor	Wires default/custom ARIA labels into row and select-all checkboxes.
src/MudBlazor/Components/DataGrid/MudDataGrid.razor.cs	Adds row label derivation/disambiguation + selection-state helpers.
src/MudBlazor/Components/DataGrid/MudDataGrid.razor	Plumbs per-row label data into cell creation.
src/MudBlazor/Components/DataGrid/DataGridVirtualizeRow.razor	Adds aria-selected row attributes + computes/passes row checkbox labels.
src/MudBlazor/Components/DataGrid/CellContext.cs	Carries per-row checkbox label through CellContext.
src/MudBlazor/Components/DataGrid/Cell.cs	Creates CellContext with optional per-row checkbox label.
src/MudBlazor.UnitTests/Components/DataGridTests.cs	Adds coverage for default/custom labels, duplicates, and aria-selected behavior.
src/MudBlazor.Docs/Pages/Components/DataGrid/Examples/DataGridSelectionExample.razor	Updates example to demonstrate AriaLabelFunc.
src/MudBlazor.Docs/Pages/Components/DataGrid/DataGridPage.razor	Documents the new ARIA label behavior and customization hook.

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[Copilot]

Pull request overview

Copilot reviewed 11 out of 11 changed files in this pull request and generated no new comments.

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[danielchalmers]

I'll have to save this for the next release so I have more time to review it

[danielchalmers]

Simplifications suggested by GPT-5.4:

• Keep the semantics, drop the heuristics. Default row checkbox label is always localized "Select row", header/footer stay "Select all rows", and AriaLabelFunc remains the escape hatch. This deletes the row-label scan, duplicate tracking, and the Cell/CellContext plumbing entirely.
• Keep the behavior, but move ownership into SelectColumn. Let SelectColumn ask the grid for a single default label for context.Item, instead of precomputing a dictionary in the row renderer. Same feature set, much less cross-component plumbing.
• Replace implicit inference with an explicit API. A RowLabelFunc or SelectionTextFunc is much easier to explain, test, and maintain than “first visible PropertyColumn, skip templates, dedupe duplicates, fallback if blank”.
• Reuse visible cell content instead of rebuilding strings. Give the first label-bearing cell an id and point the checkbox at it with aria-labelledby or aria-describedby. That keeps the accessible text aligned with rendered content and avoids CellContent(item)?.ToString() drift.
• If you want the smallest possible PR, question whether aria-selected belongs here yet. I didn’t find grid roles on the DataGrid, so row-level aria-selected may be less valuable than just giving the checkboxes good names and checked state. That would cut the row-attribute logic down to almost nothing.
• If duplicate disambiguation is the main source of churn, consider dropping it. Repeated accessible names are usually tolerable; the checkbox is already inside a row with visible context. B-1 / B-2 feels more like over-specification than core accessibility value.
• If duplicate disambiguation must stay, use row index directly instead of a two-pass duplicate scan. "Select row B (row 2)" is cheaper than counting duplicate labels first.
• Pull label inference into a small pure helper and test that helper directly. Right now the bUnit tests are asserting a lot of implementation detail, which is making the PR feel larger than the feature.

[danielchalmers]

🤖💬 e48c593 keeps the key accessibility improvements but removes the parts that were doing too much guessing.

What stays:

• built-in labels for row and select-all checkboxes
• AriaLabelFunc for explicit per-row customization
• aria-selected only when selection semantics come from SelectColumn
• no aria-selected for disabled rows

What changed:

• the default row label is always the localized "Select row" instead of trying to infer text from visible row content

Why this is better:

• it preserves the accessibility win without adding a heuristic system
• it removes the extra plumbing through MudDataGrid, row rendering, Cell, and CellContext
• it avoids brittle behavior around TemplateColumn, hidden columns, duplicate values, formatting, and future column types
• it leaves richer labeling available through the explicit API instead of guesswork
• it makes the code, tests, and docs much smaller and easier to maintain

[versile2]

Verdict:

The ARIA implementation is valid and accessible.
For optimal user experience, row-specific labels are preferred, but "Select row" is an acceptable fallback and meets minimum accessibility requirements.

Final Verdict & Feedback:

The PR is focused, well-documented, and thoroughly tested.
Accessibility is improved and customizable.
No critical issues found; all review checklist items are satisfied.****