Accessibility in Blazor Chart Component

28 Mar 20245 minutes to read

The Blazor Chart component followed the accessibility guidelines and standards, including ADA, Section 508, WCAG 2.2 standards, and WCAG roles that are commonly used to evaluate accessibility.

The accessibility compliance for the Blazor Chart component is outlined below.

Accessibility Criteria Compatibility
WCAG 2.2 Support Yes
Section 508 Support Yes
Screen Reader Support Yes
Right-To-Left Support Yes
Color Contrast Yes
Mobile Device Support Yes
Keyboard Navigation Support Yes
Axe-core Accessibility Validation Yes
Yes - All features of the component meet the requirement.
Intermediate - Some features of the component do not meet the requirement.
No - The component does not meet the requirement.

WAI-ARIA attributes

WAI-ARIA(Accessibility Initiative - Accessible Rich Internet Applications) defines a way to increase the accessibility of web pages, dynamic content, and user interface components developed with AJAX, HTML, JavaScript, and related technologies. ARIA provides additional semantics to describe the role, state, and functionality of web components.

Element Default description
Datalabel Reads the Point y value.
Legend Click to show or hide the series.
Axis Title Reads the axis title.
Chart Title Reads the chart title.
Series Points Reads the Point x: Point y value.

The Blazor Chart component followed the WAI-ARIA patterns to meet the accessibility. The following ARIA attributes are used in the Blazor Chart component:

  • img (role)
  • button (role)
  • region (role)
  • aria-label (attribute)
  • aria-hidden (attribute)
  • aria-pressed (attribute)

Keyboard navigation

The Blazor Chart component followed the keyboard interaction guideline, making it easy for people who use assistive technologies (AT) and those who completely rely on keyboard navigation. The following keyboard shortcuts are supported by the Blazor Chart component.

Interaction Keys Description
Alt + J Moves the focus to the chart element.
Tab Moves the focus to the next element in the chart.
Shift + Tab Moves the focus to the previous element in the chart.
DownArrow Moves the focus to the data point right side from the selected point.
UpArrow Moves the focus to the data point right side from the selected point.
Left Arrow Moves the focus to the next series in our Chart component.
Right Arrow Moves the focus to the previous series in our Chart component.
Enter/Space Selects the data point in the series
Down/Left Arrow Moves the focus to the legend left side from the selected legend.
Up/Right Arrow Moves the focus to the legend right side from the selected legend.
Enter/Space Toggles the visibility of the corresponding series.
Ctrl + + Zoom in the chart.
Ctrl + - Zoom out the chart.
Down/Up Arrow Pans the chart vertically.
Left/Right Arrow Pans the chart horizontally.
R Reset the zoomed chart.
Ctrl + P Prints the Chart.

Ensuring accessibility

The Blazor Chart component’s accessibility levels are ensured through an axe-core with playwright tests.

The accessibility compliance of the Blazor Chart component is shown in the following sample. Open the sample in a new window to evaluate the accessibility of the Blazor Chart component with accessibility tools.

See also