Focus

Set the focus in the view

<StackPanel FocusManager.FocusedElement="{Binding ElementName=tb}"> <TextBox Name="tb" />

Set the focus in the code behind

this.tb.Focus();

Set Focus from ViewModel

MainWindow.xaml

<Window xmlns:local="clr-namespace:MyNamespace" <TextBox local:FocusBehavior.IsFocused="{Binding FilterIsFocused, Mode=OneWay}">

MainVM.cs

FilterIsFocused = true; private bool _filterIsFocused; public bool FilterIsFocused { get { return _filterIsFocused; } set { Set(() => FilterIsFocused, ref _filterIsFocused, value); } }

FocusBehavior.cs

public static class FocusBehavior { public static readonly DependencyProperty IsFocusedProperty = DependencyProperty.RegisterAttached( "IsFocused", //EXEMPT:GLOBALIZATION typeof(bool), typeof(FocusBehavior), new FrameworkPropertyMetadata( false, new PropertyChangedCallback(onIsFocusedPropertyChanged))); public static bool GetIsFocused(DependencyObject element) { //ArgumentCheck.IsNotNull(element, "element"); return (bool)element.GetValue(IsFocusedProperty); } public static void SetIsFocused(DependencyObject element, bool value) { //ArgumentCheck.IsNotNull(element, "element"); element.SetValue(IsFocusedProperty, value); } private static void onIsFocusedPropertyChanged(DependencyObject element, DependencyPropertyChangedEventArgs args) { UIElement target = element as UIElement; if (target == null) { return; } bool isFocused = (bool)args.NewValue; if (!isFocused) { return; } // Delay the call to allow the current batch of processing to finish before we shift focus. target.Dispatcher.BeginInvoke( (Action)(() => { if (target.Focusable) { target.Focus(); } }), DispatcherPriority.Input); } }