# Keyboard Support

This article demonstrates the usage and the advantages that the **RadTrewView** provides through its keyboard support. 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, keyboard navigation and key commands.

**RadTreeView** provides two aspects of keyboard support:

## Focus the control

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 **RadTreeView** and enables keyboard navigation.

**Example**: Setting the **KeyboardNavigationSettings** for **RadTreeView**

```ASPNET
<telerik:RadTreeView RenderMode="Lightweight" ID="RadTreeView1" runat="server" TabIndex="1">
    <KeyboardNavigationSettings CommandKey="Alt" FocusKey="W" />
</telerik:RadTreeView>
```

The **KeyboardNavigationSettings** exposes two properties to configure the keyboard combination that sets focus to the control:

* **FocusKey**: An upper-case letter or number.

* **CommandKey**: \[Ctrl] , \[Alt] or \[Shift].

Pressing the keys set to these two properties at the same time places the focus on the TreeView. The user can then use the arrow keys for navigation.

![RadTreeView ArrowKey Navigation](https://www.telerik.com/products/aspnet-ajax/documentation/assets/7db5dc629160ba09134d973e0618d518/treeview_keyboardsupport01g.gif)

> note Note that in some browsers certain keyboard combinations are already occupied and used by the browser itself.

## Arrow Key Navigation and Key Commands

Allows end-users to navigate around the TreeView structure using the arrow keys, as well as to use the **Plus**, **Minus**, **Space**, **Enter**, and **F2** keys for additional control:

* The **Left Arrow** will collapse the current node or navigate to the parent node if the current node is already collapsed.

* The **Right Arrow** will expand the current node or navigate to the first child node if the current node is already expanded.

* The **Plus/Minus** keys will expand/collapse the current node.

* The **Up/Down** arrows will move the node selection one node up/down respectively.

* The **Enter** key will select the node and fire its event.

* Typing a letter key moves focus to the next instance of a visible node whose title begins with that letter.

* The **Space** key will check/uncheck the current node (in case it has a checkbox).

* **Home** key moves to the top node in the TreeView.

* **End** key moves to the last visible node in the TreeView.

* **Ctrl + Arrow** to an item with the keyboard focuses the item (but does not select it). Previous selections are maintained, provided that the **Ctrl** key is not released or that some other keyboard function is not performed.

* **Shift + Up Arrow** extends selection up one node.

* **Shift + Down Arrow** extends selection down one node.

* **Shift + Home** extends selection up to the top-most node.

* **Shift + PageDown** extends selection down to the last node.

* **Ctrl + Space** with focus on an item toggles the selection of the item.

* **F2** key will make the node text editable (in case the **AllowNodeEditing** property is set to **true**). Click **Enter** to confirm, **Esc** to cancel.

* **(asterisk)** on keypad expands all nodes.

**Example 2**: Demonstration of some of the key Navigations of the **RadTrewView**.
![RadTreeView ArrowKey Navigation](https://www.telerik.com/products/aspnet-ajax/documentation/assets/e6af2582d69a9b410b235d15ae9b8e57/treeview_keyboardsupport02.gif)

> note The **RadTreeView** keyboard support is implemented according to the [W3C Specification. ](https://www.w3.org/TR/2010/WD-wai-aria-practices-20100916/#TreeView)