Accessibility in Blazor AutoComplete Component

9 Dec 20226 minutes to read

The AutoComplete component has been designed, keeping in mind the WAI-ARIA specifications, and applies the WAI-ARIA roles, states, and properties along with keyboard support. This component is characterized by complete keyboard interaction support and ARIA accessibility support that makes it easy for people who use assistive technologies (AT) or those who completely rely on keyboard navigation.

ARIA attributes

The AutoComplete component uses the combobox role and each list item has an option role. The following ARIA Attributes denotes the AutoComplete state:

Property	Functionalities
aria-haspopup	Indicates whether the AutoComplete input element has a suggestion list or not.
aria-expanded	Indicates whether the suggestion list has expanded or not.
aria-selected	Indicates the selected option from the list.
aria-readonly	Indicates the readonly state of the AutoComplete element.
aria-disabled	Indicates whether the AutoComplete component is in disabled state or not.
aria-activedescendent	This attribute holds the ID of the active list item to focus its descendant child element.
aria-owns	This attribute contains the ID of the suggestion list to indicate popup as a child element.
aria-autocomplete	This attribute contains the ‘both’ to a list of options shows and the currently selected suggestion also shows inline.

Keyboard interaction

You can use the following key shortcuts to access the AutoComplete without interruptions:

Keyboard shortcuts	Actions
Arrow Down	In popup hidden state, opens the suggestion list. In popup open state, selects the first item when no item selected else selects the item next to the currently selected item.
Arrow Up	In popup hidden state, opens the suggestion list. In popup open state, selects the last item when no item selected else selects the item previous to the currently selected one.
Page Down	Scrolls down to the next page and selects the first item when popup list opens.
Page Up	Scrolls up to previous page and selects the first item when popup list opens.
Enter	Selects the focused item and set to AutoComplete component.
Tab	Focuses the next tab indexed element when the popup is closed. Otherwise, closes the popup list and remains the focus in component if it is in open state.
Shift + tab	Focuses the previous tab indexed element when the popup is closed. Otherwise, closes the popup list and remains the focus in component if it is in open state.
Alt + Down	Opens the popup list.
Alt + Up	In popup hidden state, opens the popup list. In popup open state, closes the popup list.
Esc(Escape)	Closes the popup list when it is in open state then removes the selection.
Home	Moves the cursor before the first character in input.
End	Moves the cursor next to the last character in input.

NOTE

In the following sample, disable the AutoComplete component using t keys.

@using Syncfusion.Blazor.DropDowns

<SfAutoComplete TValue="string" TItem="Country" @ref="AutoObj" Placeholder="Select a country" Enabled="@enable" @onkeypress="@(e => KeyPressed(e))" DataSource="@LocalData">
    <AutoCompleteFieldSettings Value="Name"></AutoCompleteFieldSettings>
</SfAutoComplete>

@code {

    public SfAutoComplete<string, Country> AutoObj;

    public bool enable { get; set; } = true ;
    public class Country
    {
        public string Name { get; set; }
        public string Code { get; set; }
    }

    List<Country> LocalData = new List<Country> {
        new Country() { Name = "Australia", Code = "AU" },
        new Country() { Name = "Bermuda", Code = "BM" },
        new Country() { Name = "Canada", Code = "CA" },
        new Country() { Name = "Cameroon", Code = "CM" },
        new Country() { Name = "Denmark", Code = "DK" },
        new Country() { Name = "France", Code = "FR" },
        new Country() { Name = "Finland", Code = "FI" },
        new Country() { Name = "Germany", Code = "DE" },
        new Country() { Name = "Greenland", Code = "GL" },
        new Country() { Name = "Hong Kong", Code = "HK" },
    };

    public void KeyPressed(KeyboardEventArgs args)
    {
        if (args.Key == "t")
        {
            enable = false;
        }
    }
}