nullability

dotnet/ios/ios11/FaceIDSample/LocalAuthentication/AuthenticationViewController.cs

@@ -1,7 +1,6 @@
 using LocalAuthentication;
 
 namespace StoryboardTable;
-
 /*
 	* https://developer.apple.com/ios/human-interface-guidelines/user-interaction/authentication/
 	*
@@ -19,9 +18,9 @@ namespace StoryboardTable;
 /// </remarks>
 partial class AuthenticationViewController : UIViewController
 {
-	LAContextReplyHandler replyHandler;
+	LAContextReplyHandler? replyHandler;
 	/// <summary>String to use for display</summary>
-	string BiometryType = "";
+	string BiometryType = string.Empty;
 
 	public AuthenticationViewController (IntPtr handle) : base (handle)
 	{
@@ -32,30 +31,22 @@ partial class AuthenticationViewController : UIViewController
 		base.ViewWillAppear (animated);
 
 		// bind every time, to reflect deletion in the Detail view
-		unAuthenticatedLabel.Text = "";
+		unAuthenticatedLabel.Text = string.Empty;
 
 		var context = new LAContext ();
-		var buttonText = "";
-		if (context.CanEvaluatePolicy(LAPolicy.DeviceOwnerAuthenticationWithBiometrics, out var authError1))
-		{ // has Biometrics (Touch or Face)
-			if (UIDevice.CurrentDevice.CheckSystemVersion(11, 0))
-			{
+		var buttonText = string.Empty;
+		if (context.CanEvaluatePolicy (LAPolicy.DeviceOwnerAuthenticationWithBiometrics, out var authError1)) { // has Biometrics (Touch or Face)
+			if (UIDevice.CurrentDevice.CheckSystemVersion (11, 0)) {
 				context.LocalizedReason = "Authorize for access to secrets"; // iOS 11
 				BiometryType = context.BiometryType == LABiometryType.TouchId ? "Touch ID" : "Face ID";
 				buttonText = $"Login with {BiometryType}";
-			}
-			else
-			{   // no FaceID before iOS 11
+			} else {   // no FaceID before iOS 11
 				buttonText = $"Login with Touch ID";
 			}
-		}
-		else if (context.CanEvaluatePolicy(LAPolicy.DeviceOwnerAuthentication, out var authError2))
-		{
+		} else if (context.CanEvaluatePolicy (LAPolicy.DeviceOwnerAuthentication, out var authError2)) {
 			buttonText = $"Login"; // with device PIN
 			BiometryType = "Device PIN";
-		}
-		else
-		{
+		} else {
 			// Application might choose to implement a custom username/password
 			buttonText = "Use unsecured";
 			BiometryType = "none";
@@ -72,76 +63,49 @@ partial class AuthenticationViewController : UIViewController
 		// because LocalAuthentication APIs have been extended over time, need to check iOS version before setting some properties
 		context.LocalizedFallbackTitle = "Fallback"; // iOS 8
 
-		if (UIDevice.CurrentDevice.CheckSystemVersion(10, 0))
-		{
+		if (UIDevice.CurrentDevice.CheckSystemVersion (10, 0)) {
 			context.LocalizedCancelTitle = "Cancel"; // iOS 10
 		}
-		if (UIDevice.CurrentDevice.CheckSystemVersion(11, 0))
-		{
+		if (UIDevice.CurrentDevice.CheckSystemVersion (11, 0)) {
 			context.LocalizedReason = "Authorize for access to secrets"; // iOS 11
 			BiometryType = context.BiometryType == LABiometryType.TouchId ? "TouchID" : "FaceID";
 		}
 
 		//Use canEvaluatePolicy method to test if device is TouchID or FaceID enabled
 		//Use the LocalAuthentication Policy DeviceOwnerAuthenticationWithBiometrics
-		if (context.CanEvaluatePolicy(LAPolicy.DeviceOwnerAuthenticationWithBiometrics, out AuthError))
-		{
-			Console.WriteLine("TouchID/FaceID available/enrolled");
-			replyHandler = new LAContextReplyHandler((success, error) =>
-			{
+		if (context.CanEvaluatePolicy (LAPolicy.DeviceOwnerAuthenticationWithBiometrics, out AuthError)) {
+			replyHandler = new LAContextReplyHandler ( (success, error) => {
 				//Make sure it runs on MainThread, not in Background
-				this.InvokeOnMainThread(() =>
-				{
-					if (success)
-					{
-						Console.WriteLine($"You logged in with {BiometryType}!");
-
+				this.InvokeOnMainThread ( () => {
+					if (success) {
 						PerformSegue ("AuthenticationSegue", this);
-					}
-					else
-					{
-						Console.WriteLine(error.LocalizedDescription);
+					} else {
 						//Show fallback mechanism here
 						unAuthenticatedLabel.Text = $"{BiometryType} Authentication Failed";
-						//AuthenticateButton.Hidden = true;
 					}
 				});
-
 			});
 			//Use evaluatePolicy to start authentication operation and show the UI as an Alert view
 			//Use the LocalAuthentication Policy DeviceOwnerAuthenticationWithBiometrics
 			context.EvaluatePolicy (LAPolicy.DeviceOwnerAuthenticationWithBiometrics, localizedReason, replyHandler);
 		}
-		else if (context.CanEvaluatePolicy(LAPolicy.DeviceOwnerAuthentication, out AuthError))
-		{
-			Console.WriteLine("When TouchID/FaceID aren't available or enrolled, use the device PIN");
-			replyHandler = new LAContextReplyHandler((success, error) =>
-			{
+		else if (context.CanEvaluatePolicy (LAPolicy.DeviceOwnerAuthentication, out AuthError)) {
+			replyHandler = new LAContextReplyHandler ( (success, error) => {
 				//Make sure it runs on MainThread, not in Background
-				this.InvokeOnMainThread(() =>
-				{
-					if (success)
-					{
-						Console.WriteLine($"You logged in with {BiometryType}!");
-
+				this.InvokeOnMainThread ( () => {
+					if (success) {
 						PerformSegue ("AuthenticationSegue", this);
-					}
-					else
-					{
-						Console.WriteLine(error.LocalizedDescription);
+					} else {
 						//Show fallback mechanism here
 						unAuthenticatedLabel.Text = "Device PIN Authentication Failed";
 						AuthenticateButton.Hidden = true;
 					}
 				});
-
 			});
 			//Use evaluatePolicy to start authentication operation and show the UI as an Alert view
 			//Use the LocalAuthentication Policy DeviceOwnerAuthenticationWithBiometrics
 			context.EvaluatePolicy (LAPolicy.DeviceOwnerAuthentication, localizedReason, replyHandler);
-		}
-		else
-		{
+		} else {
 			// User hasn't configured a PIN or any biometric auth.
 			// App may implement its own login, or choose to allow open access
 			unAuthenticatedLabel.Text = "No device auth configured";

dotnet/ios/ios11/FaceIDSample/LocalAuthentication/DetailViewController.cs

@@ -2,7 +2,7 @@
 
 public partial class DetailViewController : UIViewController
 {
-	object detailItem;
+	object? detailItem;
 
 	public DetailViewController (IntPtr handle) : base (handle)
 	{
@@ -21,7 +21,7 @@ public partial class DetailViewController : UIViewController
 	void ConfigureView ()
 	{
 		// Update the user interface for the detail item
-		if (IsViewLoaded && detailItem != null)
+		if (IsViewLoaded && detailItem is not null)
 			detailDescriptionLabel.Text = detailItem.ToString ();
 	}
 

dotnet/ios/ios11/FaceIDSample/LocalAuthentication/GlobalSuppressions.cs

@@ -0,0 +1,8 @@
+// This file is used by Code Analysis to maintain SuppressMessage
+// attributes that are applied to this project.
+// Project-level suppressions either have no target or are given
+// a specific target and scoped to a namespace, type, member, etc.
+
+using System.Diagnostics.CodeAnalysis;
+
+[assembly: SuppressMessage("Interoperability", "CA1416:Validate platform compatibility", Justification = "<Pending>", Scope = "member", Target = "~M:StoryboardTable.SecretTableSource.GetCell(UIKit.UITableView,Foundation.NSIndexPath)~UIKit.UITableViewCell")]

dotnet/ios/ios11/FaceIDSample/LocalAuthentication/SecretItem.cs

@@ -11,7 +11,7 @@ public class SecretItem {
 	}
 
 	public int Id { get; set; }
-	public string Name { get; set; }
-	public string Notes { get; set; }
+	public string Name { get; set; } = string.Empty;
+	public string Notes { get; set; } = string.Empty;
 	public bool Done { get; set; }
 }

dotnet/ios/ios11/FaceIDSample/LocalAuthentication/SecretTableSource.cs

@@ -14,16 +14,26 @@ public class SecretTableSource : UITableViewSource {
 		}.ToArray ();
 	}
 	public override nint RowsInSection (UITableView tableview, nint section)
-	{
-		return tableItems.Length;
-	}
+		=> tableItems.Length;
+
 	public override UITableViewCell GetCell (UITableView tableView, Foundation.NSIndexPath indexPath)
 	{
 		// in a Storyboard, Dequeue will ALWAYS return a cell,
 		UITableViewCell cell = tableView.DequeueReusableCell (cellIdentifier);
 		// now set the properties as normal
+
+		// Beginning in iOS 14, UITableViewCell has to use cell.ContentConfiguration
+		// to add text
+		if (UIDevice.CurrentDevice.CheckSystemVersion(14, 0)) {
+			var content = cell.DefaultContentConfiguration;
+			content.Text = tableItems[indexPath.Row].Name;
+			content.SecondaryText = tableItems[indexPath.Row].Notes;
+			cell.ContentConfiguration = content;
+		} else {
 			cell.TextLabel.Text = tableItems[indexPath.Row].Name;
 			cell.DetailTextLabel.Text = tableItems[indexPath.Row].Notes;
+		}
+
 		return cell;
 	}
 	public override void RowSelected (UITableView tableView, Foundation.NSIndexPath indexPath)