I want to access the IoC Container from the FinishedLoading and the RegisteredForRemoteNotifications/OpenUrl functions in the App Delegate, is this possible?
I tried to access the container after the App was initialised in the Finishedloading function but it throws an error saying it's unable to resolve.
public override bool FinishedLaunching(UIApplication app, NSDictionary options)
{
global::Xamarin.Forms.Forms.Init();
var iosApp = new App(new iOSInitializer());
LoadApplication(iosApp);
var container = iosApp.Container;
_appModel = container.Resolve<IAppModel>();
_configuration = container.Resolve<IConfiguration>();
_notificationService = container.Resolve<INotificationService>();
return base.FinishedLaunching(app, options);
}
Adding DryIoc namespace worked for me.
using DryIoc;
Related
I am able to start my Windows MAUI app using an URI, and I can get the URI itself. But, it appears that a NEW instance of the app is being created. This is not ideal for me -- if my app is already running, I want to use that instance.
I have done something like this for a Xamarin.Forms app. I override OnActivated in Application class.
Re: my MAUI app, I'm not even clear on whether the issue is how I've done the "protocol" in package.appxmanifest, or if it is how I respond to lifecycle events.
The default behaviour is to run multiple instances of your app. You can make the app single-instanced by defining a customized class with a Main method as suggested in this blog post:
[STAThread]
static async Task Main(string[] args)
{
WinRT.ComWrappersSupport.InitializeComWrappers();
bool isRedirect = await DecideRedirection();
if (!isRedirect)
{
Microsoft.UI.Xaml.Application.Start((p) =>
{
var context = new DispatcherQueueSynchronizationContext(
DispatcherQueue.GetForCurrentThread());
SynchronizationContext.SetSynchronizationContext(context);
new App();
});
}
return 0;
}
private static async Task DecideRedirection()
{
bool isRedirect = false;
AppActivationArguments args = AppInstance.GetCurrent().GetActivatedEventArgs();
ExtendedActivationKind kind = args.Kind;
AppInstance keyInstance = AppInstance.FindOrRegisterForKey("randomKey");
if (keyInstance.IsCurrent)
{
keyInstance.Activated += OnActivated;
}
else
{
isRedirect = true;
await keyInstance.RedirectActivationToAsync(args);
}
return isRedirect;
}
There is an open suggestion to simplify this process available on GitHub.
I am busy writing an application where the user needs to capture a lot of images and then they get packaged together with some text data and then they get uploaded to a local server. I want to implement the uploading on the Android platform through an Intent Service but I cannot find a good Xamarin Forms PCL example to show me how.
This is the method where I initialize the Intent to pass to the IntentService:
public async Task<bool> UploadAsync(Uri serviceAddress,
CaptureEntity capture,
List<ImageEntity> images)
{
try
{
Intent uploadIntent = new Intent();
uploadIntent.PutExtra("serviceAddress", serviceAddress.ToString());
uploadIntent.PutExtra("captureId", capture.WorkflowId.ToString());
StartService(uploadIntent);
return true;
}
catch (Exception exc)
{
App.logger.LogError(DateTime.Now, "Uploader", exc.ToString());
throw exc;
}
}
And this is the IntentService itself.
[Service]
public class ServiceIntent : IntentService
{
public ServiceIntent() : base("ServiceIntent")
{
}
//[return: GeneratedEnum]
public override StartCommandResult OnStartCommand(Intent intent, [GeneratedEnum] StartCommandFlags flags, int startId)
{
return base.OnStartCommand(intent, flags, startId);
}
public override void OnCreate()
{
base.OnCreate();
}
protected override void OnHandleIntent(Intent intent)
{
Uri serviceAddress = new Uri(intent.GetStringExtra("serviceAddress"));
Guid captureId = Guid.Parse(intent.GetStringExtra("captureId"));
CaptureEntity capture = new DatabaseConnection_Android().CreateConnection().Query<CaptureEntity>("SELECT * FROM [CaptureEntity]").Single(c => c.WorkflowId == captureId);
var images = new DatabaseConnection_Android().CreateConnection().Query<ImageEntity>("SELECT * FROM [ImageEntity]").Where(i => i.CaptureEntityId == capture.Id);
try
{
MultipartFormDataContent content = new MultipartFormDataContent();
StringContent strContent = new StringContent(
capture.XmlData,
Encoding.UTF8,
"text/xml");
IImageHandler handler = new ImageHandler_Droid();
HttpRequestMessage request = new HttpRequestMessage();
request.Headers.Add("workflow", capture.WorkflowId.ToString());
request.Method = HttpMethod.Post;
request.RequestUri = serviceAddress;
foreach (var image in images)
{
byte[] imageByte = handler.ReadAllBytes(image.ImagePath);
ByteArrayContent byteContent = new ByteArrayContent(imageByte);
byteContent.Headers.Add("Content-Type", "image/jpeg");
content.Add(byteContent, "file", image.ImageName);
}
content.Add(strContent, "text/xml");
request.Content = content;
using (HttpClient client = new HttpClient())
{
client.Timeout = TimeSpan.FromSeconds(180);
var response = client.SendAsync(
request,
HttpCompletionOption.ResponseContentRead).Result;
var readResponse = response.Content.ReadAsStringAsync().Result;
if (readResponse == "File uploaded.")
MessagingCenter.Send<CaptureEntity, string>(
capture,
"Completed",
"Success");
else if (readResponse.Contains("An error has occurred."))
MessagingCenter.Send<CaptureEntity, string>(
capture,
"Uploader",
String.Format(CultureInfo.InvariantCulture,
"Failed: {0}",
readResponse));
else
MessagingCenter.Send<CaptureEntity, string>(
capture,
"Uploader",
String.Format(CultureInfo.InvariantCulture,
"Failed: {0}",
readResponse));
}
}
catch (WebException webExc)
{
MessagingCenter.Send<string, string>("Uploader", "Failed",
String.Format(CultureInfo.InvariantCulture,
"{0} upload failed.\n{1}",
capture.DisplayName,
webExc.Message));
}
catch (TimeoutException timeExc)
{
MessagingCenter.Send<string, string>("Uploader", "Failed",
String.Format(CultureInfo.InvariantCulture,
"{0} upload failed.\n{1}",
capture.DisplayName,
timeExc.Message));
}
catch (Exception exc)
{
MessagingCenter.Send<string, string>("Uploader", "Failed",
String.Format(CultureInfo.InvariantCulture,
"{0} upload failed.\n{1}",
capture.DisplayName,
exc.Message));
}
}
}
Can anyone tell me what I am doing wrong as I am getting the following error when I want to start the service:
Java.Lang.NullPointerException: Attempt to invoke virtual method 'android.content.ComponentName android.content.Context.startService(android.content.Intent)' on a null object reference
In your Intent declaration you need to tell the service you want to call
Something like this:
var uploadIntent = new Intent(this, typeof(ServiceIntent));
Note: this represents the Context.
Update:
As mentioned in the comments your interface implementation cannot derive from Activity class. In order to have access to the Context to be able to call the StartService method and also create your Intent you can make it in two ways:
Using the Xamarin.Forms.Forms.Context:
public async Task<bool> UploadAsync(Uri serviceAddress,
CaptureEntity capture,
List<ImageEntity> images)
{
try
{
var context = Xamarin.Forms.Forms.Context;
var uploadIntent = new Intent(context, typeof(ServiceIntent));
uploadIntent.PutExtra("serviceAddress", serviceAddress.ToString());
uploadIntent.PutExtra("captureId", capture.WorkflowId.ToString());
context.StartService(uploadIntent);
return true;
}
catch (Exception exc)
{
App.logger.LogError(DateTime.Now, "Uploader", exc.ToString());
throw exc;
}
}
If you are using latest versions of Xamarin.Forms this global context was deprecated and they suggest to you local context instead. You can still use it though but in future updates of XF your app might break.
using CurrentActivity plugin:
public async Task<bool> UploadAsync(Uri serviceAddress,
CaptureEntity capture,
List<ImageEntity> images)
{
try
{
var context = CrossCurrentActivity.Current.Activity;
var uploadIntent = new Intent(context, typeof(ServiceIntent));
uploadIntent.PutExtra("serviceAddress", serviceAddress.ToString());
uploadIntent.PutExtra("captureId", capture.WorkflowId.ToString());
context.StartService(uploadIntent);
return true;
}
catch (Exception exc)
{
App.logger.LogError(DateTime.Now, "Uploader", exc.ToString());
throw exc;
}
}
This plugin can be installed from nugget and the setup is very straight forward. Basically it gives you access to the current activity and you can use it as your context to call the IntentService
Hope this helps.-
Here is the IntentService.
IntentService is a base class for Services that handle asynchronous requests (expressed as Intents) on demand. Clients send requests through startService(Intent) calls; the service is started as needed, handles each Intent in turn using a worker thread, and stops itself when it runs out of work.
In Android, we usually use IntentService to do asynchronous operator. As we all know, thread is also used to do asynchronous operator. The difference between IntentService and Thread is IntentService is Service which belongs to Android Component. So, the priority of IntentService is higher than Thread.
For example, there is a ActivityA which has a IntentService, and there is a ActivityB which has a Thread, both IntentService and Thread are working, and both ActivityA and ActivityB are al background Activity. Now, if your phone's system doesn't have extra resources, your ActivityB will be killed firstly.
About the Exception:
Java.Lang.NullPointerException: Attempt to invoke virtual method 'android.content.ComponentName android.content.Context.startService(android.content.Intent)' on a null object reference
That means you should use android.content.Context to call the StartService method. In Android, there are three kinds of Context. Application, Activity and Service. So you can call the StartService method in these three classes directly. If you are not in these three classes, you need pass the Context to your class, and then use the Context to call StartService.
I added Activity for this class' inheritance.
If you do this, your class will be a Activity, and you need to register it in your manifiest, add layout for your class, and it should have the lifecycle, and etc. It will not be what you want to get class. In Android, Activity is a Component, not normal class, so you can't inherit it unless you want your class to be a Activity.
Demo:
I have made a demo for you,
So, either I am asking incorrectly, or it isn't possible, let's see which...
If my app (Xamarin.Forms) is launched from another app, in order to get a url from my app, how do I return that data to the calling app? I wrongly assumed SetResult and Finish, I also wrongly assumed StartActivityForResult, but there has to be a way to do this. I know how to get data INTO my app from another app, but not the same in return.
POSSIBLE PARTIAL SOLUTION -- UPDATE, FAILS
So I have to setup an interface in my PCL, and call the method from the listview item selected handler, in the Android app I can then do this:
Intent result = new Intent("com.example.RESULT_ACTION", Uri.parse("content://result_url"));
setResult(Activity.RESULT_OK, result);
finish();
(source: https://developer.android.com/training/basics/intents/filters.html)
Is this looking right, and how would I implement the same thing on iOS?
END
I deleted my previous question because I couldn't explain the problem clearly, so here goes.
I have a Xamarin Forms app, I want to use a section of this app as a gallery. Currently I have images displayed in a list, and I have an Intent filter set that launches this page when you select the app as the source for an image (such as upload image on Facebook).
My issue is that I don't know how to return the data (the selected image) back to the app / webpage that made the request. In android I understand that you would use StartActivityForResult and OnActivityResult to handle this, but I am using Xamarin Forms (Android, iOS, UWP) and can't really find a solution that could be used cross-platform.
Just a link to documentation that covers this would be great, but if you have an example then even better.
Thanks
EDIT
Here is the code used to launch the app, I am interested in getting data back from the Intent.ActionPick after the user has selected an image from a ListView, which is in a ContentPage in the PCL.
[Activity(Label = "", Icon = "#drawable/icon", Theme = "#style/DefaultTheme", MainLauncher = true, LaunchMode = LaunchMode.SingleTop,
ConfigurationChanges = ConfigChanges.ScreenSize | ConfigChanges.Orientation)]
[IntentFilter(new[] { Intent.ActionSend }, Categories = new[] { Intent.CategoryDefault }, DataMimeType = #"*/*")]
[IntentFilter(new[] { Intent.ActionView, Intent.ActionPick, Intent.ActionGetContent }, Categories = new[] { Intent.CategoryDefault, Intent.CategoryOpenable }, DataMimeType = #"*/*")]
public class MainActivity : FormsAppCompatActivity
{
protected override void OnCreate(Bundle bundle)
{
try
{
base.OnCreate(bundle);
CurrentPlatform.Init();
Xamarin.Forms.Forms.Init(this, bundle);
App _app = new App();
LoadApplication(_app);
if (Intent.Action == Intent.ActionSend)
{
var image = Intent.ClipData.GetItemAt(0);
var imageStream = ContentResolver.OpenInputStream(image.Uri);
var memOfImage = new System.IO.MemoryStream();
imageStream.CopyTo(memOfImage);
_app.UploadManager(memOfImage.ToArray()); //This allows me to upload images to my app
}
else if (Intent.Action == Intent.ActionPick)
{
_app.SelectManager(); //here is where I need help
}
else
{
_app.AuthManager(); //this is the default route
}
}
catch (Exception e)
{
}
}
It seems you cannot use remote URI to provide to calling app. Some posts I checked suggest to store the file locally and provide it's path to calling app. To avoid memory leak with many files stored I suggest to use the same file name then you will have only one file at any moment.
One more note. I tested this solution in facebook. Skype doesn't seem to accept that and, again, the posts I checked saying that Skype doesn't handle Intent properly (not sure what that means).
Now to solution. In main activity for example in OnCreate method add the follow.
ReturnImagePage is the name of my page class where I select an image
Xamarin.Forms.MessagingCenter.Subscribe<ReturnImagePage, string>(this, "imageUri", (sender, requestedUri) => {
Intent share = new Intent();
string uri = "file://" + requestedUri;
share.SetData(Android.Net.Uri.Parse(uri));
// OR
//Android.Net.Uri uri = Android.Net.Uri.Parse(requestedUri);
//Intent share = new Intent(Intent.ActionSend);
//share.PutExtra(Intent.ExtraStream, uri);
//share.SetType("image/*");
//share.AddFlags(ActivityFlags.GrantReadUriPermission);
SetResult(Result.Ok, share);
Finish();
});
Above will listen for the message when the image is selected.
Then in XFroms code when image is selected dowload it, store it, get path and send to Activity using it's path. Below is my test path
MessagingCenter.Send<ReturnImagePage, string>(this, "imageUri", "/storage/emulated/0/Android/data/ButtonRendererDemo.Droid/files/Pictures/temp/IMG_20170207_174559_21.jpg");
You can use static public class to save and access results like:
public static class StaticClass
{
public static int Result;
}
I have a picture of item in external storage (that was saved by intent in my app). I want to display this picture in Image view in my shared project.
Image.Source takes object of ImageSource type. I tried ImageSource.FromFile, ImageSource.FromStream and even ImageSource.FromUri. The result is always that image is not displayed (no error or exception). I validated that the path to file is correct by first opening it with File.Open one line above.
What is the correct way of displaying pictures from normal storage, not from assets/resources/etc?
This code does not work:
var path = "/storage/emulated/0/Pictures/6afbd8c6-bb1e-49d3-838c-0fa809e97cf1.jpg" //in real app the path is taken from DB
var image = new Image() {Aspect = Aspect.AspectFit, WidthRequest = 200, HeightRequest = 200};
image.Source = ImageSource.FromFile(path);
Your Xamarin Forms PCL don't know what its a URI from Android beacuse its platform specific, so:
ImageSource.FromFile(path);
won't work.
In that case you are handling platform specific features, that is loading an image from Android.
I suggest this approach:
Create an interface on Xamarin Forms PCL like:
public interface IPhoto
{
Task<Stream> GetPhoto ();
}
Then in Android you implement that interface and register the implementation in DependencyService:
[assembly: Xamarin.Forms.Dependency(typeof(PhotoImplementation))]
namespace xpto
{
public class PhotoImplementation : Java.Lang.Object, IPhoto
{
public async Task<Stream> GetPhoto()
{
// Open the photo and put it in a Stream to return
var memoryStream = new MemoryStream();
using (var source = System.IO.File.OpenRead(path))
{
await source.CopyToAsync(memoryStream);
}
return memoryStream;
}
}
}
In the Xamarin Forms PCL code get the image:
var image = ImageSource.FromStream ( () => await DependencyService.Get<IPhoto>().GetPhoto());
For more detail you can consult this.
NOTE1: This will work on iOS if you implement the interface IPhoto too.
NOTE2: There exist a helpful library for this kind of features from Xamarin-Forms-Labs called Camera.
UPDATE (Shared Project solution)
As requested in the comments, to use this in a Shared Project instead of PCL we could do this.
1 - Place the IPhotoInterface in the Shared Project.
2 - Implement the interface in Android/iOS project:
public class PhotoImplementation : IPhoto
{
public async Task<Stream> GetPhoto()
{
// Open the photo and put it in a Stream to return.
}
}
3 - Use it in the Shared Project:
IPhoto iPhotoImplementation;
#if __ANDROID__
iPhotoImplementation = new shared_native.Droid.GetPicture();
#elif __IOS__
iPhotoImplementation = new shared_native.iOS.GetPicture();
#endif
var image = ImageSource.FromStream ( () => await iPhotoImplementation.GetPhoto());
NOTE: shared_native is the namespace of my solution and Droid/iOS are the projects for Android and iOS.
I am new to xamarin.in my project open gallery for select image for this i have used IMediaPicker interface.my code as below:
IMediaPicker mediaPicker;
ImageSource imageSource;
async void OnTapEntertainer(object sender, EventArgs args)
{
await TakePicture();
}
private async Task TakePicture()
{
mediaPicker = DependencyService.Get<IMediaPicker>();
imageSource = null;
var mediaFile = await mediaPicker.SelectPhotoAsync(new CameraMediaStorageOptions
{
DefaultCamera = CameraDevice.Front,
MaxPixelDimension = 400
});
imageSource = ImageSource.FromStream(() => mediaFile.Source);
Imgmn.Source = imageSource;
}
I got mediaPicker is null value in this code.Please help me to solve this issue.
I have added capability required for perform function.
To use MediaPicker item from XLabs please double check you have comleted all the items below:
Add a reference to XLabs.IoC to all of your projects (PCL, Android, iOS, etc.)
Initialize Resolver using the following code snippet:
var resolverContainer = new SimpleContainer();
resolverContainer.Register<IMediaPicker, MediaPicker>()
.Register<IDependencyContainer>(t => resolverContainer);
Resolver.SetResolver(resolverContainer.GetResolver());
Put this code before Xamarin.Forms.Forms.Init method for each platform in your solution.
Use var mediaPicker = Resolver.Resolve<IMediaPicker>(); to get the instance.
As per the comments following process resolves the issue:
Add Dependency Service class in .Droid library project to resolve IMediaPicker as given in example and use [assembly:Xamarin.Forms.Dependency(typeof(MediaPicker))] Reference