I'm developing an app using Xamarin's HCE feature.
The project structure is as follows.
hceSample
hceSample.Android
hceSample.iOS
I am implementing hce simulation code called hceService in hceSample, not hceSample.Android.
A function called Enable_Card exists in the hce service, and you want to use the NfcFCardEmulation.EnableService function in that function.
Activity and ComponentName are requested as parameters of the function.
The ComponentName area was handled easily, but I don't know how to get the Activity. Please advise.
This is the contents of enable_Card function of hceService.
private Activity activity = null;
private bool enable_Card(cardModel card)
{
try
{
sid = card.cardSN;
tag = "Felica";
emulation.EnableService(, componentName); //<- How to get Activity??
emulation.SetNfcid2ForService(componentName, sid);
return true;
}
catch
{
return false;
}
}
This is my first time asking a question on Stackoverflow.
I would appreciate it if you could point out any missing or incorrect parts.
I trying this
activity = Xamarin.Essentials.Platform.CurrentActivity; //<- this function is not found!
Added missing information!
The namespace of the Enable_Card function is located in hceSample.Service.
Are you using the NfcFCardEmulation.EnableService(Activity, ComponentName) Method, right?
The method is an android api from android sdk,you cannot use it directly in xamarin.form(yours is hceSample) project.
If you want to call the function in xamarin form project(hceSample) from native platform(hceSample.Android, or hceSample.iOS),you can use Xamarin.Forms DependencyService to achieve this.
The DependencyService class is a service locator that enables Xamarin.Forms applications to invoke native platform functionality from shared code.
For more information about DependencyService, you can check document Xamarin.Forms DependencyService. And there is a sample included in above document,which is helpful for you to understand DependencyService.
Note:
We recognize that hardware service is the right and ideal way to
implement in each OS project. However, I'm curious if there is a way
to code Android and iOS at the same time
Since the api you used is from android sdk, you can call it in native android or use DependencyService to call it on xamarin.form(yours is hceSample) project.
If you call it on xamarin.form(yours is hceSample) project, you also need to find the the corresponding function or interface in iOS.
Related
The application I am working with uses AppCenter with code like this:
public App()
{
InitializeComponent();
VersionTracking.Track();
VersionChecks();
VersionChecks();
DB.CreateTables();
DB.GetSettings();
DB.PopulateTables();
SetDeviceInfo();
SetResourceColors();
SetResourceDimensions();
MainPage = new AppShell();
}
protected override void OnStart()
{
AppCenter.Start("xx", typeof(Crashes), typeof(Push));
Analytics.TrackEvent(VersionTracking.CurrentVersion);
}
Although I don't see any error messages when it starts up I am concerned about the way this is coded as from what I can see the App constructor fires first followed by the OnStart().
So if this happens, how can VersionTracking work. Should that code not be in the OnStart and how about the additional code that I have which sets up the application?
Would appreciate any advice that people can offer about the use of AppCenter with Xamarin forms.
Answer
Yes, you can use Xamarin.Essentials.VersionTracking in the constructor of App.
Explanation
You are confusing three different SDKs: Xamarin.Essentials, Xamarin.Forms and AppCenter.
VersionTracking is an API in Xamarin.Essentials.
App is a subclass of the Xamarin.Forms.Application API.
AppCenter.Start is an API in the AppCenter
These are three independent SDKs and each can be used independently of the others.
Xamarin.Forms app startup flow is like : Native App Startup -> Xamarin.Forms.Application Startup
Your App class is instantiated only after Native app has finished loading.
As versioning is managed by native app, there is no problem in initialising VersionTracking in constructor, as Native app has fully loaded by this time.
I'm actually working on a Xamarin Forms application that need push notifications. I use the Plugin.PushNotification plugin.
When the app is running in the foreground or is sleeping (OnSleep), I have no problem to open a specific page when I click on a notification that I receive. But I was wondering how can I do that when the app is closed. Thanks!
I finally found the answer by myself and I want to share it in case someone needs it.
Nota bene: according to the official documentation of the plugin, it's Xam.Plugin.PushNotification that is deprecated. I use the new version of this plugin, Plugin.PushNotification which uses FCM for Android and APS for iOS.
There is no significant differences to open a notif when the app is running, is sleeping or is closed. Just add the next callback method in the OnCreate method (MyProject.Droid > MainApplication > OnCreate) and FinishedLaunching method (MyProject.iOS > AppDelegate > FinishedLaunching):
CrossPushNotification.Current.OnNotificationOpened += (s, p) =>
{
// manage your notification here with p.Data
App.NotifManager.ManageNotif(p.Data);
};
Common part
App.xaml.cs
// Static fields
// *************************************
public static NotifManager NotifManager;
// Constructor
// *************************************
public App()
{
...
NotifManager = new NotifManager();
...
}
NotifManager.cs
public class NotifManager
{
// Methods
// *************************************
public void ManageNotif(IDictionary<string, object> data)
{
// 1) switch between the different data[key] you have in your project and parse the data you need
// 2) pass data to the view with a MessagingCenter or an event
}
}
Unfortunately there is no succinct answer for either platform. Generally speaking, you need to tell the OS what to do when it starts the app as a result of the push notification. On both platforms, you should also consider what API level you are targeting, otherwise it won't work or even crash the app.
On iOS, you will need to implement this method in AppDelegate appropriately: FinishedLaunching(UIApplication application, NSDictionary launchOptions). The launchOptions will have the payload from the push notification for you to determine what to do with it (e.g. what page to open). For more information on iOS, Xamarin's documentation is a good place to start.
Android has a more complicated topology in terms of more drastic differences between API levels, whether you are using GCM/FCM, as well as requiring more code components. However, to answer the question directly, you will need to handle this in OnCreate(Bundle savedInstanceState) of your main Activity. If you are using Firebase, the push notification payload is available in Intent.Extras. Again, Xamarin's documentation has a good walkthrough.
Finally, note that the Plugin.PushNotification library you are using has been deprecated. I suggest you either change your library and/or your implementation soon. Part of the reason that library has been deprecated is because Google has deprecated the underlying Google Cloud Messaging (GCM) service, which will be decommissioned on April 11, 2019.
I created a Cross Platform Xamarin Forms app. In the Portable Class I have a WebView that loads a web page from a URL.
From my Android project, I would like to be able to change the WebView URL.
What is the best way to do this ? I am kind of new to this, so any help to point me in the right direction would be great.
Thank you
I had a similar scenario in which I wanted to read the received SMS in Android project and send the message to PCL project.
For that I used Xamarin's MessagingCenter:
In Android's activity, upon receiving the SMS, I used the following code to send the SMS message body back to PCL:
MessagingCenter.Send<RegisterSecondPage, string>
(new RegisterSecondPage(), "OtpReceived", code);
And in one of my PCL pages I received it back like this:
MessagingCenter.Subscribe<RegisterSecondPage, string>
(new RegisterSecondPage(), "OtpReceived", async (s, code) =>
{
ActivationCode = code;
});
I believe you can use similar scenario as well.
I'm programming in Xamarin.Forms (PCL), and I have seen many post but none one works for me. I'm using the plugin PhoneCall.Forms.Plugin
I made a method to call with a button that contains the next code
try
{
var PhoneCallTask = CrossMessaging.Current.PhoneDialer;
if (PhoneCallTask.CanMakePhoneCall)
{
PhoneCallTask.MakePhoneCall("+528331607211", "Laura");
}
else
{
DisplayAlert("Llamada", "No se puede hacer llamada", "Ok");
}
}
It throws an error:
System.NotlmplementedException: This functionality is not implemented in the portable version of this assembly. You should reference the NuGet package from your main application project in order to reference the platform-specific implementation.
Have you tried the Messaging plugin?
Like said by Jason here.
Try:
Device.OpenUri(new Uri("tel:528331607211"));
If you are using this plugin (I'm not sure if this is the specific one you're using or not), then you need to make the phone call using a Dependency service (This is explained in the plugin readme).
Make a method in your PCL project to call the dependancy service:
private void QCall(string number)
{
var notificator = DependencyService.Get<IPhoneCall>();
notificator.MakeQuickCall (number);
}
In each platform specific project, initialize the plugin. For Android, this will be done in the OnCreate method of your MainActivity, and for iOS in AppDelegate in the FinishedLaunching method. Add the following line to each after the initialization of Xamarin.Forms:
PhoneCallImplementation.Init();
Then when you call QCall() in your PCL project it will run the code necessary for the specific platform the user is on.
I am developing an Xamarin.forms application, I need to catch the imei number of mobile that is using the application. I am aware of how it is done in Android. But how can I do the same in Xamarin.forms. Please educate me.
There is no 'Forms-way' of doing this. If you know how on Android you can make use of the DependencyService. Which means in your shared project create an interface like:
public interface IImeiService
{
string GetImei();
}
Now in your Android project implement this interface, so it would be something like:
public class ImeiService : IImeiService
{
public string GetImei()
{
// ... Implement your Android code here
}
}
Register your Android code with an attribute on the class above the namespace
[assembly: Xamarin.Forms.Dependency (typeof (ImeiService))]
namespace ImeiApp.Droid {
You can now access it, back in your shared code, with:
var imei = DependencyService.Get<IImeiService>().GetImei();
If you would have an iOS implementation you could repeat the same steps, although you can, of course, use the same interface and call in shared code, so you will only need a iOS specific implementation.
However, since iOS 7 Apple disallows access to this kind of information programmatically, so you cannot get the IMEI number. And if you can, you will use code that will not be allowed through the App Store review process.