Xamarin.IOS go back from CNContactViewController.FromContact to Application - ios

Question

I have an application written with Xamarin for IOS and Android where I have a list of contacts and when I click on one of them I want to open the according contact in the addressbook of the phone. I have an interface for that implement the method on IOS that way:
private void ShowContactDialog(string addressbookId, bool isEdit = false)
{
var contact = new AddressBookService().GetCnContactById(addressbookId);
var view = CNContactViewController.FromContact(contact);
view.Editing = isEdit;
DisplayView(view);
}
private static void DisplayView(CNContactViewController view)
{
var window = UIApplication.SharedApplication.KeyWindow;
var vc = window.RootViewController;
while (vc.PresentedViewController != null)
{
vc = vc.PresentedViewController;
}
if (vc is UINavigationController navController)
{
vc = navController.ViewControllers.Last();
}
vc.PresentViewController(new UINavigationController(view), true, null);
}
That works so far as it opens the contact:
The issue now is, that there is just an edit button, but now Done, cancel or back button. Therefore I have to kill the whole application and start it again to come back.
Is there a way to add a extra button similar to the edit button to dismiss the dialog again?
EDIT: I adjusted the code as suggested in the comments by Kevin Li.
private void ShowContactDialog(string addressbookId, bool isEdit = false)
{
var contact = new AddressBookService().GetCnContactById(addressbookId);
var view = CNContactViewController.FromContact(contact);
view.Editing = isEdit;
GetCurrentViewController().NavigationController.PushViewController(view, true);
}
private static UIViewController GetCurrentViewController()
{
var window = UIApplication.SharedApplication.KeyWindow;
var vc = window.RootViewController;
while (vc.PresentedViewController != null)
{
vc = vc.PresentedViewController;
}
if (vc is UINavigationController navController)
{
vc = navController.ViewControllers.Last();
}
return vc;
}
Now it is shown within the Tabs:
Unfortunately is the back button not displayed as well.
I tried to make a new UINavigationController, but that didn't change anything.
EDIT2:
I adjusted the way the tabs are created another time. My MainViewController looks like that:
[MvxRootPresentation(WrapInNavigationController = true)]
public class MainViewController : MvxTabBarViewController<MainViewModel>
{
private bool constructed;
private bool firstTimePresented = true;
public MainViewController()
{
constructed = true;
// need this additional call to ViewDidLoad because UIkit creates the view before the C# hierarchy has been constructed
ViewDidLoad();
}
public override async void ViewWillAppear(bool animated)
{
base.ViewWillAppear(animated);
if (firstTimePresented)
{
// Initialize the tabs
firstTimePresented = false;
await ViewModel.GoToContactListCommand.ExecuteAsync();
await ViewModel.GoToBirthdayListCommand.ExecuteAsync();
await ViewModel.GoToProfileListCommand.ExecuteAsync();
await ViewModel.GoToSettingsCommand.ExecuteAsync();
}
}
public override void ViewDidLoad()
{
if (!constructed)
return;
base.ViewDidLoad();
Title = "Connect Update";
EdgesForExtendedLayout = UIRectEdge.None;
View.BackgroundColor = UIColor.White;
}
}
On each View who shall be a tab has to be this Attribute:
[MvxTabPresentation(TabIconName = "IconCake", TabName = "Birthdays")]
public partial class BirthdayView : MvxViewController<BirthdayViewModel>
The code for opening the contact is the same as above. Now it makes a new View without the tabs but with the back button, exactly as wished :)

Answer 1

The issue now is, that there is just an edit button, but now Done, cancel or back button.
It is because the value of isEdit at view.Editing = isEdit; is false. So, when you present the CNContactViewController, there's only an Edit button. When you click the Edit button, it will change to the editing mode and the Cancel and Done buttons will appear.
Or you can set the value of isEdit to true, then the Cancel and Done buttons will show when the CNContactViewController presents.
Therefore I have to kill the whole application and start it again to come back.
Is there a way to add a extra button similar to the edit button to dismiss the dialog again?
You don't have to kill and restart the app to dismiss the dialog. You can just implement the DidComplete in the delegate: CNContactViewControllerDelegate to dismiss the dialog when user finishes editing the contact and click the Done button or cancel it with clicking the Cancel button.
Here's the related code snippet:
var view = CNContactViewController.FromContact(contact);
view.Delegate = new MyCNConatactViewControllerDelegate();
public class MyCNConatactViewControllerDelegate : CNContactViewControllerDelegate
{
public override void DidComplete(CNContactViewController viewController, Contacts.CNContact contact)
{
viewController.NavigationController.DismissViewController(true, null);
}
}
Update:
To show the Back button in the CNContactViewController:
Make sure the UI hierarchy like this: Navigation->Viewcontroller(Page)->CNContactViewController. Then change the method from Present to Push to show the CNContactViewController, like this:
this.NavigationController.PushViewController(view, true);