Pass ReactiveObject ViewModel between Android Activity in Xamarin

I am using ReactiveObject

both ViewModel

in Xamarin.PCL

:

public class PlanViewerViewModel : ReactiveObject

      

        
        
        
      

    

There ViewModel

is a lot of logic inside ReactiveUI

, for example:

FilterIssueTypeCommand = ReactiveCommand.Create<string, List<IGrouping<int, StandardIssueTypeTable>>>(
                searchTerm => 
                {
                    Func<StandardIssueTypeTable, bool> filterIssueType = d =>
                        string.IsNullOrEmpty(this.IssueTypeSearchQuery) ? true :
                        Contains(d.Title, this.IssueTypeSearchQuery) ||
                        Contains(d.Category.Title, this.IssueTypeSearchQuery) ||
                        Contains(d.Issues.Count().ToString(), this.IssueTypeSearchQuery);

                    return RealmConnection.All<StandardIssueTypeTable>().Where(filterIssueType)
                                          .GroupBy(g => g.CategoryId)
                                          .ToList();
                }
            );

this.WhenAnyValue(x => x.IssueTypeSearchQuery)
    .Throttle(TimeSpan.FromMilliseconds(500), RxApp.MainThreadScheduler)
    .Select(x => x?.Trim())
    .DistinctUntilChanged()
    .InvokeCommand(FilterIssueTypeCommand);

_groupedStandardIssueType = FilterIssueTypeCommand.ToProperty(this, x => x.GroupedStandardIssueType, new List<IGrouping<int, StandardIssueTypeTable>>());

      

        
        
        
      

    

In development, Xamarin.iOS

I could easily pass ViewModel

between each controller with this code:

var finderController = segue.DestinationViewController as PVFinderTabBarController;
finderController.ViewModel = this.ViewModel;

      

        
        
        
      

    

I am wondering how could I do this in Xamarin.Android

?

I know there are several ways to transfer data between Activity

:

• Give it as string
  
  , int
  
  , bool
  
  : This is what I'm using now
• Serialize object to JSON
  
  : slow
• Embed Parcelable
  
  or Serializable
  
  : I don't want to use it because that means I need to copy the project ViewModel
  
  to Xamarin.Android
  
  .

If I do that, there is no point in using ReactiveUI

.

I am thinking to use the class Application

in Android

and create one instance of mine ViewModel

in it so that everyone Activity

can reference this. Something like that:

[Application]
public class GlobalState: Application
{
    public PlanViewerViewModel viewModel { get; set; }
}

      

        
        
        
      

    

Is there any other solution?