Failed to instantiate the default view controller for UIMainStoryboardFile

Question

I am writing a small sample app with Xamarin and MvvmCross 6.4.2. I completed the Xamarin.Android version and am now starting the Xamarin.iOS version. I created a view controller for the first screen:

public class SignInViewController : MvxViewController<SignInViewModel>
{
    public SignInViewController() : base(nameof(SignInViewController), null)
    {
        
    }

    public override void ViewDidLoad()
    {
        // never gets called...

        base.ViewDidLoad();
    }
}

When I run the app, I just get a blank screen and ViewDidLoad never gets called. In the application output it says:

Failed to instantiate the default view controller for UIMainStoryboardFile 'Main' - perhaps the designated entry point is not set?

My Main.storyboard is blank and I tried to modify it in Xcode Interface Builder to set my SignInViewController as the entry point, but I couldn't figure out how.

Answer 1

Failed to instantiate the default view controller for UIMainStoryboardFile 'Main' - perhaps the designated entry point is not set?

This error happens due to a simple mistake in your storyboard. When your app starts, iOS needs to know precisely which view controller needs to be shown first – known as your default view controller.

To fix it, add a ViewController to your Main.Storyboard and set it as Inital View Controller.

Refer: how-to-fix-the-error-failed-to-instantiate-the-default-view-controller-for-uimainstoryboardfile

And there are two SignInViewController in your project.

Use this one:

public partial class SignInViewController : UIViewController
{
    public SignInViewController (IntPtr handle) : base (handle)
    {
    }

    public override void ViewDidLoad()
    {
        // never gets called...

        base.ViewDidLoad();

        View.BackgroundColor = UIColor.Red;
    }
}

Update: