Integrating third party controller with MVVMCross on MonoTouch - xamarin.ios

Question

I want to use a third party view controller that already inherits from UIViewController (https://bitbucket.org/thedillonb/monotouch.slideoutnavigation/src/f4e51488598b/MonoTouch.SlideoutNavigation?at=master), how would I integrate that with MVVMCross?
I could just take the source and change it to inherit from MvxViewController, but guessing I will run into this with other libraries.
Do I need to implement all the interfaces MvxViewController does? IMvxTouchView? IMvxEventSourceViewController?

Answer 1

For this particular case, where you don't actually want to do any data-binding so you can just use a custom presenter - e.g. see #Blounty's answer, or see this project demo - https://github.com/fcaico/MvxSlidingPanels.Touch
If you ever do need to convert third party ViewController base classes so that they support data-binding, then the easiest way is exactly what you guessed:
inherit from them to provide an EventSource-ViewController
inherit from the EventSource-ViewController to add the Mvx BindingContext
This technique is exactly how MvvmCross itself extends each of UIViewController, UITableViewController, UITabBarController, etc in order to provide data-binding.
For example, see:
extending UIViewController to provide an eventsource - MvxEventSourceViewController.cs
extending the event source ViewController to provide a binding context - MvxViewController.cs
Note that because C# doesn't have any Multiple-Inhertiance or any true Mixin support, this adaption of ViewControllers does involve a little cut-and-paste, but we have tried to minimise this through the use of event hooks and extension methods.
If it helps, this iOS technique for a previous MvvmCross version was discussed in Integrating Google Mobile Analytics with MVVMCross (obviously this is out of date now - but the general principles kind of remain the same - we adapt an existing viewcontroller via inheritance)
In Android, a similar process is also followed for Activity base classes - see ActionBarSherlock with latest MVVMCross

Answer 2

You can use a custom view presenter like below, This is pretty much straight out of my app using the SlideOutNavigation.
public class Presenter
: IMvxTouchViewPresenter
{
private readonly MvxApplicationDelegate applicationDelegate;
private readonly UIWindow window;
private SlideoutNavigationController slideNavigationController;
private IMvxTouchViewCreator viewCreator;
public Presenter(MvxApplicationDelegate applicationDelegate, UIWindow window)
{
this.applicationDelegate = applicationDelegate;
this.window = window;
this.slideNavigationController = new SlideoutNavigationController();
this.slideNavigationController.SlideWidth = 200f;
this.window.RootViewController = this.slideNavigationController;
}
public async void Show(MvxViewModelRequest request)
{
var creator = Mvx.Resolve<IMvxTouchViewCreator>();
if (this.slideNavigationController.MenuView == null)
{
// TODO: MAke this not be sucky
this.slideNavigationController.MenuView = (MenuView)creator.CreateView(new MenuViewModel());
((MenuView) this.slideNavigationController.MenuView).MenuItemSelectedAction = this.MenuItemSelected;
}
var view = creator.CreateView(request);
this.slideNavigationController.TopView = (UIViewController)view;
}
public void ChangePresentation(MvxPresentationHint hint)
{
Console.WriteLine("Change Presentation Requested");
}
public bool PresentModalViewController(UIViewController controller, bool animated)
{
Console.WriteLine("Present View Controller Requested");
return true;
}
public void NativeModalViewControllerDisappearedOnItsOwn()
{
Console.WriteLine("NativeModalViewControllerDisappearedOnItsOwn");
}
private void MenuItemSelected(string targetType, string objectId)
{
var type = Type.GetType(string.Format("App.Core.ViewModels.{0}ViewModel, AppCore", targetType));
var parameters = new Dictionary<string, string>();
parameters.Add("objectId", objectId);
this.Show(new MvxViewModelRequest { ViewModelType = type, ParameterValues = parameters });
}
}