Accessibility in Blazor Chart Component

24 Aug 20223 minutes to read

Accessibility is achieved in the Chart component through WAI-ARIA standard and keyboard navigation. The chart features can be effectively accessed through assistive technologies such as screen readers.

WAI-ARIA

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.

The following ARIA attributes are used in the chart:

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.

Keyboard navigation

Chart functionalities can be interactive with keyboard shortcuts.

The following keyboard shortcuts are supported by Chart.

Interaction Keys Description
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.
ESC Cancel the tooltip for the data point.
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.