Creating the PostDetail View & ViewModel

I will not post all the codes here and you can get the codes from the GitHub repo: https://github.com/yanxiaodi/MvvmCrossDemo. I also created a new Comment model, a service interface and the implementation for comments. Now look at the codes in the PostDetailViewModel:

namespace MvvmCrossDemo.Core.ViewModels
{
public class PostDetailViewModel : MvxViewModel
{
private readonly IPostService _postService;
public PostDetailViewModel(IPostService postService)
{
_postService = postService;
}
public override void Prepare()
{
// This is the first method to be called after construction
CommentList = new MvxObservableCollection<Comment>();
}
public override async Task Initialize()
{
// Async initialization, YEY!
await base.Initialize();
}
#region Post;
private Post _post;
public Post Post
{
get => _post;
set => SetProperty(ref _post, value);
}
#endregion
#region CommentList;
private MvxObservableCollection<Comment> _commentList;
public MvxObservableCollection<Comment> CommentList
{
get => _commentList;
set => SetProperty(ref _commentList, value);
}
#endregion
private async Task GetPost(int postId)
{
var response = await _postService.GetPost(postId);
if (response.IsSuccess)
{
Post = response.Result;
}
}
private async Task TaskGetComments(int postId)
{
var response = await _postService.GetComments(postId);
if (response.IsSuccess)
{
CommentList.AddRange(response.Result);
}
}
}
}

In this ViewModel, we have to get the postId from the previous view for the data initialization. But how to pass the param to the PostDetailViewModel?