在wpf mvvm中单击按钮时将集合绑定到xamdatagrid

如何在wpf mvvm中单击按钮将集合绑定到xamdatagrid？

XAML

   <Button Command="{Binding ButtonCommand}">Button</Button>
   <DataGrid ItemsSource="{Binding MyCollection}">
   ...
   configure columns to MyRowViewModel
   ...
   </DataGrid>

当命令被调用时，更改集合或创建并wpf自动更新网格

   public class MyViewModel
   {
     public ICommand ButtonCommand {get;set;}
     public ObservableCollection<MyRowViewModel> MyCollection {get;set;}
   }

   View.DataContext = viewModel;