Keyboard Support

The DataForm allows you to navigate through the items without using the mouse.

The utilization of the keys can entirely replace the usage of the mouse by providing shortcuts for navigation and editing.

Shortcuts

The DataForm supports the following keyboard shortcuts:

SHORTCUT	DESCRIPTION
Right Arrow	Moves the focus one cell to the right.
Left Arrow	Moves the focus one cell to the left.
Ctrl & Home	Moves the current item to the first position.
Ctrl & Left Arrow	Moves the current item to the first position.
Ctrl & End	Moves the current item to the last position.
Ctrl & Right Arrow	Moves the current item to the last position.
F2	Starts the edit mode.
Insert	Adds a new item.
Enter	Commits the edit operation.
Escape	Cancels the edit operation.
Delete	Deletes the current item.

Custom Keyboard Command Provider

The DataForm provides an MVVM-friendly approach for customizing of the default logic of its commands.

The component also enables you to extend the way the component handles a particular key by creating your own custom command provider and predefining the behavior for that key.

The following example demonstrates the implementation of this approach—you have to create a separate class, inherit the DataFormCommandProvider, and then override the ProvideCommandsForKey(KeyEventArgs args) method. In this way you will adjust only the required undesired behavior.

Create Custom KeyboardCommandProvider

public class CustomKeyboardCommandProvider : DataFormCommandProvider 
{ 
    public CustomKeyboardCommandProvider() 
        : base(null) 
    { 
    } 
    public CustomKeyboardCommandProvider(RadDataForm dataForm) 
        : base(dataForm) 
    { 
        this.DataForm = dataForm; 
    } 
    public override List<DelegateCommandWrapper> ProvideCommandsForKey(KeyEventArgs args) 
    { 
        List<DelegateCommandWrapper> actionsToExecute = base.ProvideCommandsForKey(args); 
        if (args.Key == Key.Right) 
        { 
            actionsToExecute.Clear(); 
            actionsToExecute.Add(new DataFormDelegateCommandWrapper(RadDataFormCommands.MoveCurrentToNext, this.DataForm)); 
            actionsToExecute.Add(new DataFormDelegateCommandWrapper(RadDataFormCommands.BeginEdit, this.DataForm)); 
        } 
        if (args.Key == Key.Left) 
        { 
            actionsToExecute.Clear(); 
            actionsToExecute.Add(new DataFormDelegateCommandWrapper(RadDataFormCommands.MoveCurrentToPrevious, this.DataForm)); 
            actionsToExecute.Add(new DataFormDelegateCommandWrapper(RadDataFormCommands.BeginEdit, this.DataForm)); 
        } 
        if (actionsToExecute.Count > 0) 
        { 
            actionsToExecute.Add(new DataFormDelegateCommandWrapper(new Action(() => { this.DataForm.AcquireFocus(); }), 100, this.DataForm)); 
            args.Handled = true; 
        } 
        return actionsToExecute; 
    } 
} 

Now, if the user presses the Left Arrow or Right Arrow keys, the focus will move to the next or previous item respectively and edit it. Remember to remove the predefined commands for that particular key by calling the Clear() method.

The last thing to do is set the CommandProvider property of the DataForm to the newly-created CustomKeyboardCommandProvider class:

Set CommandProvider in XAML

<Grid.Resources> 
    <my:CustomKeyboardCommandProvider x:Key="CustomProvider"/> 
</Grid.Resources> 
<telerik:RadDataForm x:Name="RadDataForm1" 
                 ItemsSource="{Binding Employees}" 
                 CommandProvider="{StaticResource CustomProvider}"/> 

Set CommandProvider in Code

this.RadDataForm1.CommandProvider = new CustomKeyboardCommandProvider(this.RadDataForm1); 

Disabling the Built-in Navigation

The DataFormCommandProvider provides a way to disable the built-in navigation by setting the EnableBuiltInNavigation property to false. By default, the built-in navigation is enabled and EnableBuiltInNavigation is set to True.

Set EnableBuiltInNavigation to False

public class NoBuiltInNavigationKeyboardCommandProvider : DataFormCommandProvider 
{ 
    public NoBuiltInNavigationKeyboardCommandProvider() 
        : base(null) 
    { 
    } 
    public NoBuiltInNavigationKeyboardCommandProvider(RadDataForm dataForm) 
        : base(dataForm) 
    { 
        this.DataForm = dataForm; 
        this.EnableBuiltInNavigation = false; 
    } 
} 

Controlling Handled Events Processing

The DataFormCommandProvider class exposes a way to manually process the handled events by setting the ShouldProcessHandledEvents of the DataFormCommandProvider to false. By default, ShouldProcessHandledEvents is set to true.

Set ShouldProcessHandledEvents to False

public class ProcessHandledEventsKeyboardCommandProvider : DataFormCommandProvider 
{ 
    public ProcessHandledEventsKeyboardCommandProvider() 
        : base(null) 
    { 
    } 
    public ProcessHandledEventsKeyboardCommandProvider(RadDataForm dataForm) 
        : base(dataForm) 
    { 
        this.DataForm = dataForm; 
        this.ShouldProcessHandledEvents = false; 
    } 
} 

See Also

• Commands Support