Foundation.ModelNotImplementedException for Local Notification in Xamarin Forms - xamarin

I have PCL project and I need to show simple notification (when a task has finished show simple string). In iOS project, when I try to show notification in ReceivedLocalNotification with:
Window.RootViewController.PresentViewController(okayAlertController, true, null);
exception is thrown: Foundation.ModelNotImplementedException: Exception of type 'Foundation.ModelNotImplementedException' was thrown. Here is a code:
public partial class AppDelegate : global::Xamarin.Forms.Platform.iOS.FormsApplicationDelegate
{
public override bool FinishedLaunching(UIApplication app, NSDictionary options)
{
ZXing.Net.Mobile.Forms.iOS.Platform.Init();
global::Xamarin.Forms.Forms.Init();
LoadApplication(new App());
if (UIDevice.CurrentDevice.CheckSystemVersion(8, 0))
{
var notificationSettings = UIUserNotificationSettings.GetSettingsForTypes(
UIUserNotificationType.Alert | UIUserNotificationType.Badge | UIUserNotificationType.Sound, null
);
app.RegisterUserNotificationSettings(notificationSettings);
// check for a notification
if (options != null)
{
// check for a local notification
if (options.ContainsKey(UIApplication.LaunchOptionsLocalNotificationKey))
{
var localNotification = options[UIApplication.LaunchOptionsLocalNotificationKey] as UILocalNotification;
if (localNotification != null)
{
UIAlertController okayAlertController = UIAlertController.Create(localNotification.AlertAction, localNotification.AlertBody, UIAlertControllerStyle.Alert);
okayAlertController.AddAction(UIAlertAction.Create("OK", UIAlertActionStyle.Default, null));
Window.RootViewController.PresentViewController(okayAlertController, true, null);
UIApplication.SharedApplication.ApplicationIconBadgeNumber = 0;
}
}
}
}
base.FinishedLaunching(app, options);
}
public override void ReceivedLocalNotification(UIApplication application, UILocalNotification notification)
{
// show an alert
UIAlertController okayAlertController = UIAlertController.Create(notification.AlertAction, notification.AlertBody, UIAlertControllerStyle.Alert);
okayAlertController.AddAction(UIAlertAction.Create("OK", UIAlertActionStyle.Default, null));
Window.RootViewController.PresentViewController(okayAlertController, true, null);
UIApplication.SharedApplication.ApplicationIconBadgeNumber = 0;
}
}
And NotificationService_iOS.cs:
public class NotificationService_iOS : INotificationService
{
public void Notify(string title, string text)
{
var notification = new UILocalNotification();
notification.FireDate = NSDate.FromTimeIntervalSinceNow(0); // Fire now
notification.AlertAction = title;
notification.AlertBody = text;
notification.ApplicationIconBadgeNumber = 1;
notification.SoundName = UILocalNotification.DefaultSoundName;
UIApplication.SharedApplication.ScheduleLocalNotification(notification);
}
}

The window object is not available, you need to use
var window = UIApplication.SharedApplication.KeyWindow;
see the answer here problem with Window object

Related

what is the best way to find out the reason that Application crashed on startup?

i am now having the problem: when I start debuging, the app crashes directly and the debug process stops. I can not see any log or error message. I don't know what can I do in this situation?
I tried to add -v -v -v -v to adtional mtouch argument. but did not see anything print out while the app just stoped the debuging.
Is there a way to solve such problem?
best regards
Lin
You should try to catch unhandled exception like this
public override bool FinishedLaunching(UIApplication app, NSDictionary options)
{
AppDomain.CurrentDomain.UnhandledException += CurrentDomainOnUnhandledException;
TaskScheduler.UnobservedTaskException += TaskSchedulerOnUnobservedTaskException;
...
#region Error handling
private void TaskSchedulerOnUnobservedTaskException(object sender, UnobservedTaskExceptionEventArgs e)
{
var newExc = new Exception("TaskSchedulerOnUnobservedTaskException", e.Exception);
LogUnhandledException(newExc);
}
private void CurrentDomainOnUnhandledException(object sender, UnhandledExceptionEventArgs e)
{
var newExc = new Exception("CurrentDomainOnUnhandledException", e.ExceptionObject as Exception);
LogUnhandledException(newExc);
}
internal static void LogUnhandledException(Exception exception)
{
try
{
const string errorFileName = "Fatal.log";
var libraryPath = System.Environment.GetFolderPath(System.Environment.SpecialFolder.Resources); // iOS: Environment.SpecialFolder.Resources
var errorFilePath = Path.Combine(libraryPath, errorFileName);
var errorMessage = string.Format("Time: {0}\r\nError: Unhandled Exception\r\n{1}",
DateTime.Now, exception.ToString());
File.WriteAllText(errorFilePath, errorMessage);
}
catch
{
// just suppress any error logging exceptions
}
}
// If there is an unhandled exception, the exception information is diplayed
// on screen the next time the app is started (only in debug configuration)
[Conditional("DEBUG")]
private static void DisplayCrashReport()
{
const string errorFilename = "Fatal.log";
var libraryPath = Environment.GetFolderPath(Environment.SpecialFolder.Resources);
var errorFilePath = Path.Combine(libraryPath, errorFilename);
if (!File.Exists(errorFilePath))
{
return;
}
var errorText = File.ReadAllText(errorFilePath);
var alertView = new UIAlertView("Crash Report", errorText, null, "Close", "Clear") { UserInteractionEnabled = true };
alertView.Clicked += (sender, args) =>
{
if (args.ButtonIndex != 0)
{
File.Delete(errorFilePath);
}
};
alertView.Show();
}
#endregion
public override bool FinishedLaunching(UIApplication app, NSDictionary options)
{
AppDomain.CurrentDomain.UnhandledException += CurrentDomainOnUnhandledException;
TaskScheduler.UnobservedTaskException += TaskSchedulerOnUnobservedTaskException;
global::Xamarin.Forms.Forms.Init();
global::XamForms.Controls.iOS.Calendar.Init();
global::ZXing.Net.Mobile.Forms.iOS.Platform.Init();
Firebase.Core.App.Configure();
Messaging.SharedInstance.Delegate = this;
DependencyService.Register<IJumpinNotificationService, JumpinNotificationService>();
DependencyService.Register<IJumpinPublicKeyValidateService, JumpinPublicKeyValidateService>();
LoadApplication(new App());
InstanceId.Notifications.ObserveTokenRefresh(TokenRefreshNotification);
if (UIDevice.CurrentDevice.CheckSystemVersion(10, 0))
{
// iOS 10 or later
var authOptions = UNAuthorizationOptions.Alert | UNAuthorizationOptions.Badge | UNAuthorizationOptions.Sound;
UNUserNotificationCenter.Current.RequestAuthorization(authOptions, (granted, error) => {
Console.WriteLine(granted);
});
// For iOS 10 display notification (sent via APNS)
UNUserNotificationCenter.Current.Delegate = this;
// For iOS 10 data message (sent via FCM)
//Messaging.SharedInstance.RemoteMessageDelegate = this;
}
else
{
// iOS 9 or before
var allNotificationTypes = UIUserNotificationType.Alert | UIUserNotificationType.Badge | UIUserNotificationType.Sound;
var settings = UIUserNotificationSettings.GetSettingsForTypes(allNotificationTypes, null);
UIApplication.SharedApplication.RegisterUserNotificationSettings(settings);
}
UIApplication.SharedApplication.RegisterForRemoteNotifications();
UNUserNotificationCenter.Current.RequestAuthorization(UNAuthorizationOptions.Alert, (approved, err) => {
// Handle approval
});
UNUserNotificationCenter.Current.GetNotificationSettings((settings) => {
var alertsAllowed = (settings.AlertSetting == UNNotificationSetting.Enabled);
});
return base.FinishedLaunching(app, options);
}

Using UIDocumentPickerViewController in Xamarin forms as a dependency service

I'm using Xamarin forms and writing a dependency service for the following objectives :
Open iOS files app. (UIDocumentPickerViewController )
Select any kind of a document.
Copy that document into my application Documents directory. (For app access)
Show that document into my application by storing its path into my SQLite DB.
What I am trying to do here is call the Files app from my application on an Entry click and the click event seems to be working well my dependency service calls perfectly but now when I try to use the UIDocumentPickerViewController I am unable to get View controller context in my dependency service to call the PresentViewController method. Now I know about the xamarin forms context but I don't know if it will work here and I don't even know if it would be a smart idea to use it as it has already been marked as obsolete and since I am not from the iOS background, I don't know what would be the right solution for it.
My code is as follows :
public class DocumentPickerRenderer : IDocumentPicker
{
public object PickFile()
{
var docPicker = new UIDocumentPickerViewController(new string[] { UTType.Data, UTType.Content }, UIDocumentPickerMode.Import);
docPicker.WasCancelled += (sender, wasCancelledArgs) =>
{
};
docPicker.DidPickDocumentAtUrls += (object sender, UIDocumentPickedAtUrlsEventArgs e) =>
{
Console.WriteLine("url = {0}", e.Urls[0].AbsoluteString);
//bool success = await MoveFileToApp(didPickDocArgs.Url);
var success = true;
string filename = e.Urls[0].LastPathComponent;
string msg = success ? string.Format("Successfully imported file '{0}'", filename) : string.Format("Failed to import file '{0}'", filename);
var alertController = UIAlertController.Create("import", msg, UIAlertControllerStyle.Alert);
var okButton = UIAlertAction.Create("OK", UIAlertActionStyle.Default, (obj) =>
{
alertController.DismissViewController(true, null);
});
alertController.AddAction(okButton);
PresentViewController(alertController, true, null);
};
PresentViewController(docPicker, true, null);
}
}
My questions:
Is my methodology correct for picking files?
what will be the object that I will be getting as a callback from a file selection and how will I get the callback?
Is there any other way or something available for xamarin forms, some guide or something that allows me to pick documents from my native file systems and gives a brief on how to handle it in both ios and android?
Hello Guys, You can use following code for picking any type of documents to mention in code using iOS Devices-
use follwing interface:
public interface IMedia
{
Task<string> OpenDocument();
}
public Task<string> OpenDocument()
{
var task = new TaskCompletionSource<string>();
try
{
OpenDoc(GetController(), (obj) =>
{
if (obj == null)
{
task.SetResult(null);
return;
}
var aa = obj.AbsoluteUrl;
task.SetResult(aa.Path);
});
}
catch (Exception ex)
{
task.SetException(ex);
}
return task.Task;
}
static Action<NSUrl> _callbackDoc;
public static void OpenDoc(UIViewController parent, Action<NSUrl> callback)
{
_callbackDoc = callback;
var version = UIDevice.CurrentDevice.SystemVersion;
int verNum = 0;
Int32.TryParse(version.Substring(0, 2), out verNum);
var allowedUTIs = new string[]
{
UTType.UTF8PlainText,
UTType.PlainText,
UTType.RTF,
UTType.PNG,
UTType.Text,
UTType.PDF,
UTType.Image,
UTType.Spreadsheet,
"com.microsoft.word.doc",
"org.openxmlformats.wordprocessingml.document",
"com.microsoft.powerpoint.ppt",
"org.openxmlformats.spreadsheetml.sheet",
"org.openxmlformats.presentationml.presentation",
"com.microsoft.excel.xls",
};
// Display the picker
var pickerMenu = new UIDocumentMenuViewController(allowedUTIs, UIDocumentPickerMode.Import);
pickerMenu.DidPickDocumentPicker += (sender, args) =>
{
if (verNum < 11)
{
args.DocumentPicker.DidPickDocument += (sndr, pArgs) =>
{
UIApplication.SharedApplication.OpenUrl(pArgs.Url);
pArgs.Url.StopAccessingSecurityScopedResource();
var cb = _callbackDoc;
_callbackDoc = null;
pickerMenu.DismissModalViewController(true);
cb(pArgs.Url.AbsoluteUrl);
};
}
else
{
args.DocumentPicker.DidPickDocumentAtUrls += (sndr, pArgs) =>
{
UIApplication.SharedApplication.OpenUrl(pArgs.Urls[0]);
pArgs.Urls[0].StopAccessingSecurityScopedResource();
var cb = _callbackDoc;
_callbackDoc = null;
pickerMenu.DismissModalViewController(true);
cb(pArgs.Urls[0].AbsoluteUrl);
};
}
// Display the document picker
parent.PresentViewController(args.DocumentPicker, true, null);
};
pickerMenu.ModalPresentationStyle = UIModalPresentationStyle.Popover;
parent.PresentViewController(pickerMenu, true, null);
UIPopoverPresentationController presentationPopover = pickerMenu.PopoverPresentationController;
if (presentationPopover != null)
{
presentationPopover.SourceView = parent.View;
presentationPopover.PermittedArrowDirections = UIPopoverArrowDirection.Down;
}
}
Now you need to call using following code:
var filePath = await DependencyService.Get<IMedia>().OpenDocument();
For pick document in Android, you can use following code
public class IntentHelper
{
public const int DocPicker = 101;
static Action<string> _callback;
public static async void ActivityResult(int requestCode, Result resultCode, Intent data)
{ if (requestCode == RequestCodes.DocPicker)
{
if (data.Data == null)
{
_callback(null);
}
else
{
var destFilePath = FilePath.GetPath(CurrentActivity, data.Data);
_callback(destFilePath);
}
}
}
public static Activity CurrentActivity
{
get
{
return (Xamarin.Forms.Forms.Context as MainActivity);
}
}
public static void OpenDocPicker(Action<string> callback)
{
_callback = callback;
var intent = new Intent(Intent.ActionOpenDocument);
intent.AddCategory(Intent.CategoryOpenable);
intent.SetType("*/*");
CurrentActivity.StartActivityForResult(intent, RequestCodes.DocPicker);
}
}
For pick document in Android, you can use following code:
public class IntentHelper
{
public const int DocPicker = 101;
static Action<string> _callback;
public static async void ActivityResult(int requestCode, Result resultCode, Intent data)
{
if (requestCode == RequestCodes.DocPicker)
{
if (data.Data == null)
{
_callback(null);
}
else
{
var destFilePath = FilePath.GetPath(CurrentActivity, data.Data);
_callback(destFilePath);
}
}
}
public static Activity CurrentActivity
{
get
{
return (Xamarin.Forms.Forms.Context as MainActivity);
}
}
public static void OpenDocPicker(Action<string> callback)
{
_callback = callback;
var intent = new Intent(Intent.ActionOpenDocument);
intent.AddCategory(Intent.CategoryOpenable);
intent.SetType("*/*");
CurrentActivity.StartActivityForResult(intent, RequestCodes.DocPicker);
}
}
Use below code to access the helper class: public class Media:
IMedia {
public Task<string> OpenDocument() {
var task = new TaskCompletionSource<string>();
try {
IntentHelper.OpenDocPicker((path) => { task.SetResult(path); });
} catch (Exception ex) {
task.SetResult(null);
}
return task.Task;
}
}
Since I was looking for UIDocumentPickerViewController and not UIDocumentMenuViewController the other answer was not what I was looking for :
So this is how I ended up doing it:
Calling the document picker:
var docPicker = new UIDocumentPickerViewController(new string[]
{ UTType.Data, UTType.Content }, UIDocumentPickerMode.Import);
docPicker.WasCancelled += DocPicker_WasCancelled;
docPicker.DidPickDocumentAtUrls += DocPicker_DidPickDocumentAtUrls;
docPicker.DidPickDocument += DocPicker_DidPickDocument;
var _currentViewController = GetCurrentUIController();
if (_currentViewController != null)
_currentViewController.PresentViewController(docPicker, true, null);
Where GetCurrentUIController is the function to get the current UI controller something like this :
public UIViewController GetCurrentUIController()
{
UIViewController viewController;
var window = UIApplication.SharedApplication.KeyWindow;
if (window == null)
{
return null;
}
if (window.RootViewController.PresentedViewController == null)
{
window = UIApplication.SharedApplication.Windows
.First(i => i.RootViewController != null &&
i.RootViewController.GetType().FullName
.Contains(typeof(Xamarin.Forms.Platform.iOS.Platform).FullName));
}
viewController = window.RootViewController;
while (viewController.PresentedViewController != null)
{
viewController = viewController.PresentedViewController;
}
return viewController;
}
For below iOS 11 i added the DidPickDocument event:
private void DocPicker_DidPickDocument(object sender, UIDocumentPickedEventArgs e)
{
try
{
NSUrl filePath = e.Url.AbsoluteUrl;
//This is the url for your document and you can use it as you please.
}
catch (Exception ex)
{
}
}
For above iOS 11 you use the DidPickDocumentUrls since multipick is supported there :
private void DocPicker_DidPickDocumentAtUrls(object sender, UIDocumentPickedAtUrlsEventArgs e)
{
try
{
List<NSUrl> filePath = e.Urls.ToList().Select(y => y.AbsoluteUrl).ToList();
//returns the list of images selected
}
catch (Exception ex)
{
AppLogger.LogException(ex);
}
}

How to use Xamarin.Auth in Xamarin.Forms (Shared Project for iOS and Android)?

I am trying to use Xamarin.Auth for a Facebook signin. It's all set up, but I am missing the last part. The Facebook signin is not my MainActivity, one has to click on a button in order to sign in. I don't know how to start the page for the signin. I have trying to follow this approach, but as my MainActivity isn't the Facebook signin page, it won't work. I have binded (I am following the MVVM pattern) the signin button and have implemented an interface in order to use DependencyService. My problem is when I have to implement the code of the platforms.
This is what I have tried on Android:
class LoginFBImpl : Activity, ILoginFB, IFacebookAuthenticationDelegate
{
public void LoginFB() //the method in the interface
{
var auth = new FacebookAuthenticator(FacebookAuthenticator.ClientId, FacebookAuthenticator.Scope, this);
var authenticator = auth.GetAuthenticator();
var intent = authenticator.GetUI(this);
StartActivity(intent); //Problem occurs here
}
public async void OnAuthenticationCompletedAsync(UserModel token)
{
var facebookService = new FacebookService();
var name = await facebookService.GetNameAsync(token.AccessToken);
var id = await facebookService.GetIdAsync(token.AccessToken);
var picture = await facebookService.GetPictureAsync(token.AccessToken);
}
public void OnAuthenticationCancelled()
{
}
public void OnAuthenticationFailed(string message, Exception exception)
{
}
}
iOS:
public class LoginFBImpl : UIViewController, ILoginFB, IFacebookAuthenticationDelegate
{
public void LoginFB()
{
var auth = new FacebookAuthenticator(FacebookAuthenticator.ClientId, FacebookAuthenticator.Scope, this);
var authenticator = auth.GetAuthenticator();
var viewController = authenticator.GetUI();
PresentViewController(viewController, true, null);
}
public async void OnAuthenticationCompletedAsync(UserModel token)
{
DismissViewController(true, null);
var facebookService = new FacebookService();
var name = await facebookService.GetNameAsync(token.AccessToken);
var id = await facebookService.GetIdAsync(token.AccessToken);
var picture = await facebookService.GetPictureAsync(token.AccessToken);
}
public void OnAuthenticationFailed(string message, Exception exception)
{
DismissViewController(true, null);
var alertController = new UIAlertController
{
Title = message,
Message = exception?.ToString()
};
PresentViewController(alertController, true, null);
}
public void OnAuthenticationCancelled()
{
DismissViewController(true, null);
var alertController = new UIAlertController
{
Title = "Authentication cancelled",
Message = "You didn't complete the authentication process"
};
PresentViewController(alertController, true, null);
}
}
I think it has something to do with the Activity/ViewController, but I don't know how to do it properly. When I run this I get: java.lang.NullPointerException: Attempt to invoke virtual method 'android.app.ActivityThread$ApplicationThread android.app.ActivityThread.getApplicationThread()' on a null object reference on Android, and I am expecting something similar on iOS - Haven't tested it yet as I am working on Windows.

Scanner is null and not accessible

I am attempting to read a QRCode in Xamarin.Forms. I have a shared project in XF. I have added the nuget packages for ZXing.Net. Everything works in the iOS project. I am getting an error in the Android project. The errors that I get via Android SDK Monitor, it indicates that there is a problem with the scanner being null and not being accessible. I am guessing that there is something that I have not set up correct on the Android side. Does anyone see anything improper in my code? Thanks for your time.
ScanPage class:
public class ScanPage : ContentPage
{
ZXing.Net.Mobile.Forms.ZXingScannerView zxing;
ZXingDefaultOverlay overlay;
bool isConnected = false;
string basicUrl = "golfeventscores.azurewebsites.net";
public ScanPage ()
{
zxing = new ZXing.Net.Mobile.Forms.ZXingScannerView
{
HorizontalOptions = LayoutOptions.FillAndExpand,
VerticalOptions = LayoutOptions.FillAndExpand,
AutomationId = "zxingScannerView",
};
zxing.OnScanResult += async (ZXing.Result result) => {
zxing.IsAnalyzing = false;
zxing.IsScanning = false;
var teamToken = result.Text;
//MessagingCenter.Send<string>(teamToken, "SelectTeamMembers");
isConnected = await Plugin.Connectivity.CrossConnectivity.Current.IsRemoteReachable(basicUrl);
if (isConnected)
{
await GetTeamData(teamToken);
}
else
{
await DisplayAlert("Connectivity", "There is a problem with internet connectivity. Please try and reload this screen.", "Ok");
}
};
overlay = new ZXingDefaultOverlay
{
TopText = "Hold your phone up to the barcode",
BottomText = "Scanning will happen automatically",
ShowFlashButton = zxing.HasTorch,
AutomationId = "zxingDefaultOverlay",
};
overlay.FlashButtonClicked += (sender, e) => {
zxing.IsTorchOn = !zxing.IsTorchOn;
};
var grid = new Grid
{
VerticalOptions = LayoutOptions.FillAndExpand,
HorizontalOptions = LayoutOptions.FillAndExpand,
};
grid.Children.Add(zxing);
grid.Children.Add(overlay);
// The root page of your application
Content = grid;
}
protected override void OnAppearing()
{
base.OnAppearing();
zxing.IsScanning = true;
}
protected override void OnDisappearing()
{
zxing.IsScanning = false;
base.OnDisappearing();
}
async System.Threading.Tasks.Task GetTeamData(string Token)
{
try
{
var scanResult = await WebServices.ws.TokenLookup(Token);
if (scanResult.Result == true)
{
if (scanResult.IsScoreBoard == true)
{
var uri = new System.Uri(scanResult.ScoreboardUrl);
Device.BeginInvokeOnMainThread(() =>
{
Device.OpenUri(uri);
Navigation.PopToRootAsync();
});
}
if (scanResult.IsCharity == true)
{
if (scanResult.TeamPlayers.Count > 0)
{
var player = scanResult.TeamPlayers.First();
var playerId = player.PlayerTeamId;
var urlResult = await WebServices.ws.ServerUrl(Token, playerId);
if (urlResult.ValidRequest && (!String.IsNullOrEmpty(urlResult.Url)))
{
var uri = new System.Uri(urlResult.Url);
Device.OpenUri(uri);
await Navigation.PopToRootAsync();
}
}
else{
await DisplayAlert("Scanning", "There was a problem downloading the Charity Team Info.", "OK");
}
}
else
{
if (scanResult.IsLargeGame != true)
{
var select = new Pages.SelectTeamMembers(Token);
await Navigation.PushAsync(select);
}
else
{
await DisplayAlert("Large Game", "Don't have the large team game setup with scanning.", "Ok");
}
}
}
else
{
await DisplayAlert("Server Problem", "There was some type of server error. Please try again or call Wally.", "Ok");
}
}
catch(System.Exception sysExc)
{
//nothing seems to be caught
}
}
}
MainActivity.cs contents:
[Activity (Label = "TD Scan", Icon = "#drawable/icon", Theme="#style/MainTheme", MainLauncher = true, ConfigurationChanges = ConfigChanges.ScreenSize | ConfigChanges.Orientation)]
public class MainActivity : global::Xamarin.Forms.Platform.Android.FormsAppCompatActivity
{
protected override void OnCreate (Bundle bundle)
{
TabLayoutResource = Resource.Layout.Tabbar;
ToolbarResource = Resource.Layout.Toolbar;
base.OnCreate (bundle);
global::Xamarin.Forms.Forms.Init (this, bundle);
ZXing.Net.Mobile.Forms.Android.Platform.Init();
LoadApplication (new GolfGameScanApp.App ());
}
public override void OnRequestPermissionsResult(int requestCode, string[] permissions, Permission[] grantResults)
{
ZXing.Net.Mobile.Android.PermissionsHandler.OnRequestPermissionsResult(requestCode, permissions, grantResults);
}
}
Have you defined all in Android Project?
Xamarin Forms
For Xamarin Forms there is a bit more setup needed. You will need to initialize the library on each platform in your platform specific app project.
Android
On Android, in your main Activity's OnCreate (..) implementation, call:
ZXing.Net.Mobile.Forms.Android.Platform.Init();
ZXing.Net.Mobile for Xamarin.Forms also handles the new Android permission request model for you, but you will need to add the following override implementation to your main Activity as well:
public override void OnRequestPermissionsResult(int requestCode, string[] permissions, Permission[] grantResults)
{
global::ZXing.Net.Mobile.Forms.Android.PermissionsHandler.OnRequestPermissionsResult (requestCode, permissions, grantResults);
}
The Camera permission should be automatically included for you in the AndroidManifest.xml however if you would like to use the Torch API's you will still need to add the Flashlight permission yourself. You can do this by using the following assembly level attribute:
[assembly: UsesPermission (Android.Manifest.Permission.Flashlight)]

ZXing(Zebra Xing) Unable to scan/ detect the barcode in Xamarin iOS

I posted couple other questions in regards to Zxing please DONT mark it duplicate just because they are about Zxing..
So, in my Xamarin iOS app, I am using Zxing to detect the barcode. I am using https://github.com/Redth/ZXing.Net.Mobile/tree/master/Samples/iOS as example.
I am using a subview to scan for barcodes. The custom overlay n everything works fine but it is unable to detect the barcode when I'm trying to scan.
Can anyone please help me out where I'm doing wrong or missing something.
CODE
public UIView camView;
AVCaptureScannerView scannerView;
UIActivityIndicatorView loadingView;
UIView loadingBg;
UIView topBg;
UIView bottomBg;
MobileBarcodeScanner scanner;
public event Action<ZXing.Result> OnScannedResult;
public MobileBarcodeScanningOptions ScanningOptions { get; set; }
public override void ViewDidLoad()
{
camView = new UIView(new CGRect(0, 0, this.View.Frame.Width, this.View.Frame.Height / 3)) { BackgroundColor = UIColor.Clear };
scanner = new MobileBarcodeScanner();
Root = new RootElement("ZXingDwatNet.Mobile") {
new Section {
camView
}
};
scannerView = new AVCaptureScannerView(camView.Frame);
camView = scannerView;
loadingBg = camView;// new UIView(this.View.Frame) { BackgroundColor = UIColor.Purple, AutoresizingMask = UIViewAutoresizing.FlexibleDimensions };
loadingView = new UIActivityIndicatorView(UIActivityIndicatorViewStyle.White)
{
AutoresizingMask = UIViewAutoresizing.FlexibleMargins
};
loadingView.Frame = new CGRect((this.View.Frame.Width - loadingView.Frame.Width) / 4,
(this.View.Frame.Height - loadingView.Frame.Height) / 4,
loadingView.Frame.Width / 4,
loadingView.Frame.Height / 4);
loadingBg.AddSubview(loadingView);
View.AddSubview(loadingBg);
loadingView.StartAnimating();
this.View.InsertSubviewBelow(scannerView, loadingView);
this.View.AutoresizingMask = UIViewAutoresizing.FlexibleWidth | UIViewAutoresizing.FlexibleHeight;
}
void HandleScanResult(ZXing.Result result)
{
string msg = "";
if (result != null && !string.IsNullOrEmpty(result.Text))
msg = "Found Barcode: " + result.Text;
else
msg = "Scanning Canceled!";
this.InvokeOnMainThread(() =>
{
var av = new UIAlertView("Barcode Result", msg, null, "OK", null);
av.Show();
});
}
public override void ViewDidAppear(bool animated)
{
//scannerView.OnScannerSetupComplete += HandleOnScannerSetupComplete;
//camView = scannerView;
var options = new MobileBarcodeScanningOptions
{
AutoRotate = false,
UseFrontCameraIfAvailable = false,
TryHarder = true
};
ScanningOptions = options;
if (UIDevice.CurrentDevice.CheckSystemVersion(7, 0))
{
UIApplication.SharedApplication.StatusBarStyle = UIStatusBarStyle.Default;
SetNeedsStatusBarAppearanceUpdate();
}
else
UIApplication.SharedApplication.SetStatusBarStyle(UIStatusBarStyle.BlackTranslucent, false);
Console.WriteLine("Starting to scan...");
Task.Factory.StartNew(() =>
{
BeginInvokeOnMainThread(() => scannerView.StartScanning(result =>
{
//if (!ContinuousScanning)
//{
// Console.WriteLine("Stopping scan...");
// scannerView.StopScanning();
//}
var evt = this.OnScannedResult;
if (evt != null)
evt(result);
}, this.ScanningOptions));
});
}
void HandleOnScannerSetupComplete()
{
BeginInvokeOnMainThread(() =>
{
if (loadingView != null && loadingBg != null && loadingView.IsAnimating)
{
loadingView.StopAnimating();
UIView.BeginAnimations("zoomout");
UIView.SetAnimationDuration(2.0f);
UIView.SetAnimationCurve(UIViewAnimationCurve.EaseOut);
loadingBg.Transform = CGAffineTransform.MakeScale(2.0f, 2.0f);
loadingBg.Alpha = 0.0f;
UIView.CommitAnimations();
loadingBg.RemoveFromSuperview();
}
});
}

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