How to bind node data as CommandParameter for TreeView ItemTemplate content in Xamarin.Forms (SfTreeView)

You can bind the node item to CommandParameter in Xamarin.Forms SfTreeview by binding with dot.

You can also refer the following article.

https://www.syncfusion.com/kb/11406/how-to-bind-node-data-as-commandparameter-for-treeview-itemtemplate-content-in-xamarin

C#

ItemInfoCommand defined to get the node data in the ViewModel.

public class FileManagerViewModel
{
    public Command<object> NodeCommand { get; set; }
    public FileManagerViewModel()
    { 
        NodeCommand = new Command<object>(OnNodeExecuted);
    }
    public void OnNodeExecuted(object data)
    {
        App.Current.MainPage.DisplayAlert("Alert", (data as FileManager).ItemName.ToString() , "OK");
    }
}

XAML

Binding (.) dot to CommandParameter of ViewModel command and will get the node data in the handler.

<Grid Grid.Column=”1”
        RowSpacing="1"
        Padding="1,0,0,0"
        VerticalOptions="Center">
    <Label LineBreakMode="NoWrap" TextColor="Black"
            Text="{Binding ItemName}"
            VerticalTextAlignment="Center">
    </Label>
    <Button Grid.Column="1" HorizontalOptions="End" Text="Node Data" CommandParameter="{Binding . }" 
    Command="{Binding Path=BindingContext.NodeCommand, Source={x:Reference treeView}}"/>
</Grid>