Pass viewmodel (contain List<ModelClass>) data to controller

Question

In my application there is an edit page, which contains a list of data through a viewmodel. this viewmodel contains two list, i.e. List<ModelClass1> and List<ModelClass2>.

 

In the view, there are multiple row of data from the lists, and i want to edit the rows and send to the controller to save the data. For this, i am usuing - @using (Html.BeginForm("Submit", "ControllerName", FormMethod.Post)) {-----}

 

however, on submit button press, when the control moves to the action method, there i found, the data is retrieving as null. below is the action method - 

public ActionResult Submit(ViewModel _ViewModel)

{

// 

} 

with a debug point, i found the view model is null for both the list.

below is the view model class - 

public class ViewModel

{

public List<Model1> Model1List { get; set; }

public List<Model2> Model2List { get; set; }

} 

 

could anyone let me know the way to pass the data to controller?