My Xamarin.iOS project keeps crashing with no explanation, and I reckon it's because of something I'm doing with SendBird, since I'm not seeing any explanation in the application output when my app crashes. How can I see logs of SendBird? This is what I am trying:
public override bool FinishedLaunching(UIApplication application, NSDictionary launchOptions)
{
// other code...
SendBird.SendBirdClient.Log = SendBirdLog;
return true;
}
private void SendBirdLog(string message)
{
// this never gets called
Console.WriteLine(message);
}
But my SendBirdLog function never gets called. I am using the latest SendBird.dll from here:
https://github.com/sendbird/Sendbird-SDK-dotNET#before-getting-started
Related
How to get notified when Xamarin Native Android app goes to sleep or is terminated?
When searching, I only found an answer for Xamarin.Forms where the Application object allows to override OnSleep.
The background of this question is that I want to save settings when the app either goes to background or is terminated.
Just like the OnSleep method of Xamarin Forms the OnPause method is called in Android Native when the app goes into the background.
You can override OnPause in both an Activity and a Fragment something like this:
protected override void OnPause()
{
base.OnPause();
// Add your code here
}
Update
You can do the same on application level by adding the Android Application class :
Add a new C# class file in your project called MainApplication.cs.
Then add the Application.IActivityLifecycleCallbacks interface where you can find the activity paused method with the activity context in which it was paused so you can add it and do the needful.
#if DEBUG
[Application(Debuggable = true)]
#else
[Application(Debuggable = false)]
#endif
public class MainApplication : Application , Application.IActivityLifecycleCallbacks
{
public MainApplication(IntPtr handle, JniHandleOwnership transer)
: base(handle, transer)
{
}
public void OnActivityPaused(Android.App.Activity activity)
{
base.OnCreate();
// Add some code
}
public override void OnTerminate()
{
base.OnTerminate();
UnregisterActivityLifecycleCallbacks(this);
}
public override void OnCreate()
{
base.OnCreate();
RegisterActivityLifecycleCallbacks(this);
}
}
I have created an application on Xamarin Forms in which I am scheduling local notifications in PCL through a Plugin named Plugin.Notifications. But I wanted to know whether the user enters into the app through notification or not.
I tried to check whether the UIApplication.LaunchOptionsLocalNotificationKey is present in the launch 'options' dictionary or not, but the launch options dictionary is always null.
Then I tried to handle it through the ReceivedLocalNotification delegate method, and I was able to get the tap event, it works fine when the app is in foreground or in the background, but when the app gets killed and opens through tapping on the notification, its getting crashed.
I am unable to find the issue for the crash.
here is what I am doing in the ReceivedLocalNotification method.
I am setting a bool value through a DependencyService.
public override void ReceivedLocalNotification(UIApplication application, UILocalNotification notification)
{
NSUserDefaults.StandardUserDefaults.Init();
DependencyService.Get<INotificationTap>().SetNoitificationTap(true);
}
The handling of the Dependency Service
[assembly: Xamarin.Forms.Dependency(typeof(NotificationTapIOS))]
namespace abc.iOS
{
public class NotificationTapIOS:NSObject,INotificationTap
{
public bool GetNotificationTap()
{
return NSUserDefaults.StandardUserDefaults.BoolForKey("notificationTapKey");
}
public void SetNoitificationTap(bool isNotificationTapped)
{
NSUserDefaults.StandardUserDefaults.SetBool(isNotificationTapped,"notificationTapKey");
NSUserDefaults.StandardUserDefaults.Synchronize();
}
}
public override bool FinishedLaunching(UIApplication app, NSDictionary options)
{
if (options != null)
{
// check for a local notification
if (options.ContainsKey(UIApplication.LaunchOptionsLocalNotificationKey))
{
var localNotification = options[UIApplication.LaunchOptionsLocalNotificationKey] as UILocalNotification;
if (localNotification != null)
{
LoadApplication(new App());
UIApplication.SharedApplication.ApplicationIconBadgeNumber = 0;// reset our badge
}
}
}
else
{
LoadApplication(new App());
}
}
I found a workaround for this issue, I don't know whether this is a correct approach, but it worked for me.
In Xamarin.iOS , when the app launched , the base class methods are called first(i.e applicationDidFinishLaunching) and then the Xamarin part(i.e FinishedLaunching) is called.
So I changed the FinishedLaunching parameters names , similar to the base class parameters (i.e 'app' to 'uiApplication' and 'options' to 'launchOptions' ) and I got the key in the launchOptions Dictionary.
public override bool FinishedLaunching(UIApplication uiApplication, NSDictionary launchOptions)
{
global::Xamarin.Forms.Forms.Init();
isNotificationTapped = false;
if (launchOptions != null) {
if (launchOptions.ContainsKey(UIApplication.LaunchOptionsLocalNotificationKey))
isNotificationTapped = true;
}
LoadApplication(new App());
return base.FinishedLaunching(uiApplication, launchOptions);
}
When the user starts the app through notification tap, then FinishedLaunching method of AppDelegate is executed and we can validate the launchOptions dictionary to find the tap event, and if the app is in background or running stage , and user taps on the notification then the RecieveLocalNotification method of the AppDelegate is called.
public override void ReceivedLocalNotification(UIApplication application, UILocalNotification notification)
{
isNotificationTapped = true;
}
After initializing the value , I saved it in the UserDefaults using the DependencyService
My project is built with master-detail navigation.
There are totally three pages in the list named as Resources, Contacts, and Login.
Everything works fine in iOS, but when the user presses the Droid/WinPhone devices hardware back button, the app should exit.
Is there any app-exit mechanism for Xamarin Forms which will work on all the devices.? (I mean native code not platform dependent)
Thanks in advance.
I did that on this way
In xamarin forms I added interface
public interface INativeHelper
{
void CloseApp();
}
In android project I made implementation of INativeHelper
public class NativeHelper : INativeHelper
{
public void CloseApp()
{
Android.OS.Process.KillProcess(Android.OS.Process.MyPid());
}
}
Implementation of INativeHelper in IOS
public class NativeHelper : INativeHelper
{
public void CloseApp()
{
Process.GetCurrentProcess().CloseMainWindow();
Process.GetCurrentProcess().Close();
}
}
And then just override method OnBackButtonPressed in page in Xamarin.Forms project
protected override bool OnBackButtonPressed()
{
INativeHelper nativeHelper = null;
nativeHelper = DependencyService.Get<INativeHelper>();
if (nativeHelper != null)
{
nativeHelper.CloseApp();
}
return base.OnBackButtonPressed();
}
I didn't made implementation for WinPhone, but it should be similar.
You can use a DepedencyService for closing an app when your physical back button is pressed:
In your UI (PCL), do the following:
protected override bool OnBackButtonPressed()
{
if (Device.OS == TargetPlatform.Android)
DependencyService.Get<IAndroidMethods>().CloseApp();
return base.OnBackButtonPressed();
}
Now implement the Android-specific logic in your Android project:
[assembly: Xamarin.Forms.Dependency(typeof(AndroidMethods))]
namespace Your.Namespace
{
public class AndroidMethods : IAndroidMethods
{
public void CloseApp()
{
Android.OS.Process.KillProcess(Android.OS.Process.MyPid());
}
}
}
Also create an Interface (in your UI PCL):
public interface IAndroidMethods
{
void CloseApp();
}
As far as I know there is no native way to exit the app in Xamarin application.
The only way is to use dependency service. Override OnBackButtonPressed function in your ContentPage and check it is the last page:
protected override bool OnBackButtonPressed()
{
if(navigation.NavigationStack.Count == 1)//navigation is MainPage.Navigation
DependencyService.Get<YourDependencyInterface>().CloseApp();
}
For Android in YourAndroidDependency class:
public void CloseApp()
{
(Xamarin.Forms.Forms.Context as Activity).Finish();
}
As for WinPhone I'm not sure but I believe it can be done in same way - dependency service.
Having experimented with all the above, I found that none of the above worked on a Google Pixel 3a, with latest version of Android
The command that came closest was
Android.OS.Process.KillProcess(Android.OS.Process.MyPid());
However it left the remains of the app still visible in the background.
The following worked for me when called from the Android Main Activity
public void ExitApp()
{
this.FinishAndRemoveTask();
Android.OS.Process.KillProcess(Android.OS.Process.MyPid());
}
The first line FinishAndRemoveTask removes the app from both the foreground and the background, however the Application process is still active, hence the need for the second command.
This is the more easy way found:
public void QuitApp(object sender, EventArgs args)
{
Process.GetCurrentProcess().CloseMainWindow();
Process.GetCurrentProcess().Close();
}
PS: Tested in android
You can use Environment.Exit(0);
My app connects to Facebook and Parse and it works well on simulator and android but it doesn't work on iOS.
The stop() (the Display.getCurrent() returns my current form) and start() methods of the main class are always called automatically. This caused my app (current form) disappeared in unexpected way. I thought the application was crashed but not.
When I double tap on the Home button I can see my app and when I select, it starts again. Any idea can help?
Thanks, William
When iOS app crashes or get killed, it doesn't remove the app from the recent apps you see when you double tap home button. It will only restart the app when you open it (Apps usually get killed on iOS within 10 minutes, depending on if the app is using any resources or not).
Verify that your app is indeed not crashing on iOS. Uncomment the crash reporter from the class that contains start() and stop() methods. This will send you an email if the app crashes and if you are a pro or higher CN1 subscriber.
Just for clarification, the class should look similar to this:
private Form current;
public void init(Object context) {
Display.getInstance().addEdtErrorHandler((evt) -> {
evt.consume();
Log.p("Exception in MyApp version " + Display.getInstance().getProperty("AppVersion", "1.0"));
Log.p("OS " + Display.getInstance().getPlatformName());
Log.p("Error " + evt.getSource());
Log.p("Current Form " + Display.getInstance().getCurrent().getName());
Log.e((Throwable) evt.getSource());
Log.sendLog();
});
}
public void start() {
if (current != null) {
current.show();
return;
}
new StateMachine("/theme");
}
public void stop() {
current = Display.getInstance().getCurrent();
}
public void destroy() {
}
I would like to know if there is a working sample for monotouch that shows a working example for receiving remote control events such as those from the headphone buttons.
I have implemented a single view iphone app, implemented CanBecomeFirstResponder, called BecomeFirstResponder and also UIApplication.SharedApplication.BeginReceivingRemoteControlEvents() but I dont get any events.
Here is my code for my SingleViewController.
public partial class SingleViewViewController : UIViewController
{
public SingleViewViewController () : base ("SingleViewViewController", null)
{
}
public override void DidReceiveMemoryWarning ()
{
// Releases the view if it doesn't have a superview.
base.DidReceiveMemoryWarning ();
// Release any cached data, images, etc that aren't in use.
}
public override void ViewDidLoad ()
{
base.ViewDidLoad ();
// Perform any additional setup after loading the view, typically from a nib.
AVAudioSession audioSession = AVAudioSession.SharedInstance();
NSError error;
audioSession.SetCategory(AVAudioSession.CategoryPlayback, out error);
audioSession.SetActive(true,out error);
this.BecomeFirstResponder();
UIApplication.SharedApplication.BeginReceivingRemoteControlEvents();
}
public override void ViewDidUnload ()
{
base.ViewDidUnload ();
// Clear any references to subviews of the main view in order to
// allow the Garbage Collector to collect them sooner.
//
// e.g. myOutlet.Dispose (); myOutlet = null;
ReleaseDesignerOutlets ();
}
public override bool ShouldAutorotateToInterfaceOrientation (UIInterfaceOrientation toInterfaceOrientation)
{
// Return true for supported orientations
return (toInterfaceOrientation != UIInterfaceOrientation.PortraitUpsideDown);
}
public override bool CanBecomeFirstResponder {
get {
return true;
}
}
public override bool CanResignFirstResponder {
get {
return false;
}
}
public override void RemoteControlReceived (UIEvent theEvent)
{
base.RemoteControlReceived (theEvent);
}
}
I spent a little bit of time on this and I think I might have an answer for you. My first faulty assumption was that the volume up and down controls on the remote (headphones) would register but they don't.
I haven't managed to confirm the following except through trial and error, but it appears that you need to have an AVAudioPlayer playing something, or at least playing something when you start the AVAudioSession. Without playing something the play / stop event gets passed to the Music app which handles it.
In your code, in the ViewDidLoad method after the call to base, I added
AVAudioPlayer player = new AVAudioPlayer(new NSUrl("Music/test.m4a", false), null);
player.PrepareToPlay();
player.Play();
If you look at chapter 27 of these samples on GitHub, you'll see an example that plays audio and handles the remote control events.
https://github.com/mattneub/Programming-iOS-Book-Examples
I wasn't able to get remote control events working without the player playing, your example matched lots of Obj-C samples but I couldn't make it work in Xcode either.
Hope this helps.