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How can I programmatically get keyboard focus in a WPF TreeViewItem?

I am trying to programmatically adjust the keyboard focus to a tree structure element (under certain conditions). I tried 2 methods for adjusting focus, both of which successfully focus on TreeViewItem, but lose keyboard focus.

The tree view is tied to the view model:

<TreeView Name="solutionsModel" TreeViewItem.Selected="solutionsModel_Selected"
          ItemsSource="{Binding Items, Mode=OneWay}" />

I am trying to set focus through a routed event TreeViewItem Selected:

private void solutionsModel_Selected(object sender, RoutedEventArgs e)
{
    if (solutionsModel.SelectedItem != null && solutionsModel.SelectedItem is SolutionViewModel)
    {
        if (e.OriginalSource != null && e.OriginalSource is TreeViewItem)
        {
            FocusManager.SetFocusedElement(solutionsModel, e.OriginalSource as TreeViewItem);
        }
    }
}

I am trying to set focus to TreeViewItemin ControlTemplate:

<Style d:IsControlPart="True" TargetType="{x:Type TreeViewItem}">
    <Setter Property="IsSelected" Value="{Binding IsSelected, Mode=TwoWay}" />
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type TreeViewItem}">
                <ControlTemplate.Triggers>
                    <Trigger Property="IsSelected" Value="true">
                        <Trigger.Setters>
                            <Setter Property="FocusManager.FocusedElement" Value="{Binding RelativeSource={RelativeSource Self}}"></Setter>
                        </Trigger.Setters>
                    </Trigger>
                    <MultiTrigger>
                        <MultiTrigger.Conditions>
                            <Condition Property="IsSelected" Value="true" />
                            <Condition Property="IsSelectionActive" Value="false" />
                        </MultiTrigger.Conditions>
                        <!--
                        <MultiTrigger.Setters>
                            <Setter Property="FocusManager.FocusedElement" Value="{Binding RelativeSource={RelativeSource Self}}"></Setter>
                        </MultiTrigger.Setters>
                        -->
                    </MultiTrigger>
                </ControlTemplate.Triggers>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

, (TreeViewItem.IsSelectionActive - false). , ( , ). , () MultiTrigger, IsSelectionActive , , , TreeViewItem.

, ?

+3
2

, , , , TreeView TreeViewItem, NeedsFocus, , .

:

    <local:ModelTreeView x:Name="solutionsModel" ItemsSource="{Binding Items, Mode=OneWay}">
    </local:ModelTreeView>

() :

<Style d:IsControlPart="True" TargetType="{x:Type local:ModelTreeViewItem}">
    <Setter Property="IsSelected" Value="{Binding IsSelected, Mode=TwoWay}" />
    <Setter Property="NeedsFocus" Value="{Binding NeedsFocus, Mode=TwoWay}" />
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type local:ModelTreeViewItem}">
                <ControlTemplate.Triggers>
                    <Trigger Property="NeedsFocus" Value="true">
                        <Trigger.Setters>
                            <Setter Property="FocusManager.FocusedElement" Value="{Binding RelativeSource={RelativeSource Self}}"></Setter>
                        </Trigger.Setters>
                    </Trigger>
                </ControlTemplate.Triggers>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

:

public class ModelTreeView : TreeView
{
    protected override DependencyObject GetContainerForItemOverride()
    {
        return new ModelTreeViewItem();
    }

    protected override bool IsItemItsOwnContainerOverride(object item)
    {
        return item is ModelTreeViewItem;
    }
}

public class ModelTreeViewItem : TreeViewItem
{
    ///--------------------------------------------------------------------------------
    /// <summary>This property gets or sets whether the item needs focus.</summary>
    ///--------------------------------------------------------------------------------
    public static readonly DependencyProperty NeedsFocusProperty = DependencyProperty.Register("NeedsFocus", typeof(bool), typeof(ModelTreeViewItem));
    public bool NeedsFocus
    {
        get
        {
            return (bool)GetValue(NeedsFocusProperty);
        }
        set
        {
            SetValue(NeedsFocusProperty, value);
        }
    }

    protected override DependencyObject GetContainerForItemOverride()
    {
        return new ModelTreeViewItem();
    }

    protected override bool IsItemItsOwnContainerOverride(object item)
    {
        return item is ModelTreeViewItem;
    }
}

NeedsFocus false IsSelected.

+2

, , TreeView TreeView.SelectedItem. , . , TreeView , .

+3

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