Hi, I've configured my treeview as follows:-
<treeView:SfTreeView Grid.Row="1" ItemsSource="{Binding Expressions}"
ChildPropertyName="Children" ExpandActionTarget="Node" AutoExpandMode="AllNodesExpanded"
ItemHeight="30" TapCommand="{Binding TreeItemTappedCommand}"
SelectedItem="{Binding SelectedCondition, Mode=TwoWay}" SelectionMode="Single">
<treeView:SfTreeView.ItemTemplate>
<DataTemplate>
<Grid>
<Label Text="Parent" />
</Grid>
</DataTemplate>
</treeView:SfTreeView.ItemTemplate>
</treeView:SfTreeView>
And have applied the patch described
here to avoid the null reference exception. This renders and behaves correctly if placed outside of a SfTabView control, however if the tree view is placed in SfTabItem then it's no longer possible to interact with the Tree view and all taps are ignored, i.e. no expansion/contraction occurs on the nodes.