A critical requirement for software accessibility is keyboard support as a complete alternative to pointing devices (mouse, etc.). Keyboard support is comprised of command key, focus key, and keyboard navigation. RadListBox seamlessly switches between mouse and keyboard navigation, allowing items selection, deletion, moving and reordering.
Setting the control's KeyboardNavigationSettings (introduced in R2 2016 - ver.2016.2.504), allows you to associate an activation combination (CommandKey + FocusKey), which moves focus directly to the RadListBox and enables keyboard navigation. When there are multiple RadListBox controls on a given page, each of them may have a different activation combination.
The KeyboardNavigationSettings exposes two properties to configure the keyboard combination that sets focus to the control:
CommandKey: [Ctrl] , [Alt] or [Shift].
FocusKey: An upper-case letter or number.
Pressing CommandKey + FocusKey sets the focus on the RadListBox and enables keyboard navigation.
Certain keyboard combinations are reserved and used as shortcuts in the browsers.
Example: Setting the KeyboardNavigationSettings for RadListBox
<telerik:RadListBox ID="RadListBox1" runat="server" > <KeyboardNavigationSettings CommandKey="Alt" FocusKey="M" /> <Items> <telerik:RadListBoxItem Text="Amsterdam" > </telerik:RadListBoxItem> <telerik:RadListBoxItem Text="Barcelona" > </telerik:RadListBoxItem> </Items> </telerik:RadListBox>
Down Arrow / Up Arrow keys select next/previous item.
Shift + Arrow Keys selects multiple items.
Ctrl + Space adds or removes the currently active item to or from the selection.
Del deletes the currently selected item (if AllowDelete is set to "true").
Ctrl + Right Arrow transfers the selected item/s to the destination RadListBox.
Ctrl + Left Arrow transfers the selected item/s to the source RadListBox when the selection is in the destination listbox.
Ctrl + Shift + Up Arrow reorders upwards.
Ctrl + Shift + Down Arrow reorders downwards.
STARTS WITH (
Start typing to highlight the matching items.
Esc clears the mask.
Backspace removes a single character.
FIRST LETTER (
Any key navigates to a matching item.
Subsequent press on the same key iterates over the matches.
Marking matches works only for the built-in items, because it relies on their
Textand structure. This means that using the
ItemTemplatewill disable the Mark Matches functionality.
For the feature to work, the
TabIndexproperty of the control must be set, otherwise it cannot receive focus and the keyboard events.