I also faced the same problem. I had three text boxes inside canvas container and wanted the first text box to be focused when the user control opens. WPF code followed MVVM pattern. I created a separate behavior class for focusing the element and binded it to my view like this.
Canvas behavior code
public class CanvasLoadedBehavior : Behavior<Canvas>{ private Canvas _canvas; protected override void OnAttached() { base.OnAttached(); _canvas = AssociatedObject as Canvas; if (_canvas.Name == "ReturnRefundCanvas") { _canvas.Loaded += _canvas_Loaded; } } void _canvas_Loaded(object sender, RoutedEventArgs e) { FocusNavigationDirection focusDirection = FocusNavigationDirection.Next; // MoveFocus takes a TraveralReqest as its argument. TraversalRequest request = new TraversalRequest(focusDirection); UIElement elementWithFocus = Keyboard.FocusedElement as UIElement; if (elementWithFocus != null) { elementWithFocus.MoveFocus(request); } }}Code for view
<Canvas Name="ReturnRefundCanvas" Height="200" Width="1466" DataContext="{Binding RefundSearchViewModel}"><i:Interaction.Behaviors><b:CanvasLoadedBehavior /></i:Interaction.Behaviors><uc:Keyboard Canvas.Left="973" Canvas.Top="111" ToolTip="Keyboard" RenderTransformOrigin="-2.795,9.787"></uc:Keyboard><Label Style="{StaticResource Devlbl}" Canvas.Left="28" Content="Return and Refund Search" Canvas.Top="10" /><Image Height="30" Width="28" Canvas.Top="6" Canvas.Left="5" Source="pack://application:,,,/HomaKiosk;component/images/searchF.png"><Image.OpacityMask><ImageBrush ImageSource="pack://application:,,,/HomaKiosk;component/images/searchF.png"/></Image.OpacityMask></Image><Separator Height="4" Canvas.Left="6" Margin="0" Canvas.Top="35" Width="1007"/><ContentControl Canvas.Top="45" Canvas.Left="21" ContentTemplate="{StaticResource ErrorMsg}" Visibility="{Binding Error, Converter={c:StringNullOrEmptyToVisibilityConverter}}" Content="{Binding Error}" Width="992"></ContentControl><Label Style="{StaticResource Devlbl}" Canvas.Left="29" Name="FirstName" Content="First Name" Canvas.Top="90" /><wpf:AutoCompleteTextBox Style="{StaticResource AutoComp}" Height="32" Canvas.Left="33" ToolTip="First Name" Canvas.Top="120" Width="205" Padding="10,5" TabIndex="1001" VerticalAlignment="Top" Watermark="" IconPlacement="Left" IconVisibility="Visible" Delay="100" Text="{Binding FirstName, Mode=TwoWay, TargetNullValue=''}" Provider="{Binding FirstNameSuggestions}"><wpf:AutoCompleteTextBox.ItemTemplate><DataTemplate><Border Padding="5"><StackPanel Orientation="Vertical"><TextBlock Text="{Binding}" FontWeight="Bold" /></StackPanel></Border></DataTemplate></wpf:AutoCompleteTextBox.ItemTemplate></wpf:AutoCompleteTextBox><Label Style="{StaticResource Devlbl}" Canvas.Left="250" Content="Last Name" Canvas.Top="90" /><wpf:AutoCompleteTextBox Style="{StaticResource AutoComp}" Height="32" ToolTip="Last Name" Canvas.Left="250" Canvas.Top="120" Width="205" Padding="10,5" TabIndex="1002" VerticalAlignment="Top" Watermark="" IconPlacement="Left" IconVisibility="Visible" Delay="100" Text="{Binding LastName, Mode=TwoWay, TargetNullValue=''}" Provider="{Binding LastNameSuggestions}"><wpf:AutoCompleteTextBox.ItemTemplate><DataTemplate><Border Padding="5"><StackPanel Orientation="Vertical"><TextBlock Text="{Binding}" FontWeight="Bold" /></StackPanel></Border></DataTemplate></wpf:AutoCompleteTextBox.ItemTemplate></wpf:AutoCompleteTextBox><Label Style="{StaticResource Devlbl}" Canvas.Left="480" Content="Receipt No" Canvas.Top="90" /><wpf:AutoCompleteTextBox Style="{StaticResource AutoComp}" Height="32" ToolTip="Receipt No" Canvas.Left="480" Canvas.Top="120" Width="205" Padding="10,5" TabIndex="1002" VerticalAlignment="Top" Watermark="" IconPlacement="Left" IconVisibility="Visible" Delay="100" Text="{Binding ReceiptNo, Mode=TwoWay, TargetNullValue=''}" Provider="{Binding ReceiptIdSuggestions}"><wpf:AutoCompleteTextBox.ItemTemplate><DataTemplate><Border Padding="5"><StackPanel Orientation="Vertical"><TextBlock Text="{Binding}" FontWeight="Bold"></TextBlock></StackPanel></Border></DataTemplate></wpf:AutoCompleteTextBox.ItemTemplate><i:Interaction.Behaviors><b:AllowableCharactersTextBoxBehavior RegularExpression="^[0-9]+$" MaxLength="15" /></i:Interaction.Behaviors></wpf:AutoCompleteTextBox><!--<Label Style="{StaticResource Devlbl}" Canvas.Left="710" Content="Duration" Canvas.Top="79" />--><!--<ComboBox AllowDrop="True" Canvas.Left="710" ToolTip="Duration" Canvas.Top="107" Width="205" TabIndex="1004" Style="{StaticResource CommonComboBox}" ItemsSource="{Binding Durations}" DisplayMemberPath="Description" SelectedValuePath="Id" SelectedValue="{Binding SelectedDate, Mode=TwoWay}"></ComboBox>--><Button Content="Search" Style="{StaticResource MyButton}" ToolTip="Search" Canvas.Top="116" Canvas.Left="710" Cursor="Hand" Command="{Binding SearchCommand}" TabIndex="2001"></Button><Button Content="Clear" Style="{StaticResource MyButton}" ToolTip="Clear" Canvas.Top="116" Canvas.Left="840" Cursor="Hand" Command="{Binding ClearCommand}" TabIndex="2002"></Button><Image Height="25" Width="25" Canvas.Top="175" Canvas.Left="25" Source="pack://application:,,,/HomaKiosk;component/images/chkpending.png"/><Label Style="{StaticResource LegendLbl}" Canvas.Left="50" Content="Check Returned and Payment Pending" Canvas.Top="178" /><Image Height="25" Width="25" Canvas.Top="175" Canvas.Left="300" Source="pack://application:,,,/HomaKiosk;component/images/chkrepaid.png"/><Label Style="{StaticResource LegendLbl}" Canvas.Left="325" Content="Repaid" Canvas.Top="178" /><Image Height="25" Width="25" Canvas.Top="175" Canvas.Left="395" Source="pack://application:,,,/HomaKiosk;component/images/refund.png"/><Label Style="{StaticResource LegendLbl}" Canvas.Left="415" Content="Refunded" Canvas.Top="178" /></Canvas>