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In Hilt, How can I Inject a context in a non activity/ fragment class using field injection?

I have a Exception Handling class
class IOException : BaseException {
#EntryPoint
#InstallIn(SingletonComponent::class)
interface AnalyticsServiceProviderEntryPoint {
fun analyticsService(): AnalyticsService
}
private val hiltEntryPoint = EntryPointAccessors.fromApplication(**Need Context**, AnalyticsServiceProviderEntryPoint::class.java)
val analyticsService = hiltEntryPoint.analyticsService()
}
If I see this offical link, it says
In this example, you must use the ApplicationContext to retrieve the
entry point because the entry point is installed in SingletonComponent
What If I don't have the context in the class and in the function body which I will use and I don't want to use from Constructor Injection as well?
I only want to use the field injection. How can I access it, since I don't have the context.

In your application add a companion object with lateinit var applicationContext and initialize the variable when the application is initialized like:
companion object {
lateinit var applicationContext: Context
private set
then you have an static variable with the application context and you can you something like:
private val hiltEntryPoint = EntryPointAccessors.fromApplication(Application.applicationContext, AnalyticsServiceProviderEntryPoint::class.java)
I can't think of anything else to do what you want to do

Did you try to get applicationContext from dagger-hilt ApplicationContextModule? Its already provided by this module in your app and you can get that probably. You need to use the qualifer also
#Provides
#ApplicationContext
Context provideContext() {
return applicationContext;
}

How to define context in a kotlin object

How can I define a context for the progressdialog within such an object
import dmax.dialog.SpotsDialog
object Constants {
//These are all the constants within our application
const val permission_request = 100
val firebaseAuth = FirebaseAuth.getInstance()
val progressDialog = SpotsDialog.Builder().setContext(thecontext).build()
}

You can give it a lateinit context property that you set in your Application class. Then make the property that's dependent on it Lazy. But in this case, it doesn't make sense, because a Dialog is transient. It wouldn't be a constant. You can't reuse dialogs, because Android destroys and recreates the Activities/Fragments that host them according to various lifecycle processes.
But if you do have something like a constant that needs a Context, this is how you could do it:
object Constants {
lateinit var context: Context
val foo by lazy { Foo(context) }
}
class MyApplication: Application() {
override fun onCreate() {
super.onCreate()
Constants.context = this
}
}
And make sure you set .MyApplication as the Application name in the manifest.

How i can use context in Singleton?

I need in my Singleton -> Context. I know that I can't passing argument in constructor, because object hasn't constructor.
Then I call it from my Application class.
Here is the code:
object Singleton {
var userAgentInfo: String = UserAgentTools.buildUserAgent(context)
fun initializeSdk() {
AuthenticatorApiManager.initializeSdk(userAgentInfo)
}
}

Move the initialization of userAgentInfo to the initializeSDK method, and send the Context as an argument, make sure to send the ApplicationContext.
object Singleton {
var userAgentInfo: String? = null
fun initializeSdk(context: Context) {
userAgentInfo = UserAgentTools.buildUserAgent(context)
AuthenticatorApiManager.initializeSdk(userAgentInfo)
}
}

Make Application class and write below code.
companion object {
private lateinit var sInstance: ApplicationClass
fun getInstance(): ApplicationClass {
return sInstance
}
}
Use in object like below.
ApplicationClass.getInstance()

You can use context in your Singleton class using Application class instance.here it is

Accessing method from Application class in Kotlin Android

I have created an application class in Kotlin. I need to access a method that returns a variable from anywhere in my application. The problem is I am not able to access that method from other parts of the program. I am able to access when code is written in Java , but when code is written in Kotlin,then the method in Application class is not accessible. Please find below code for reference:
class MyRetroApplication : Application() {
lateinit var apiComponent:APIComponent
companion object {
var ctx: Context? = null
}
override fun onCreate() {
super.onCreate()
ctx = applicationContext
apiComponent = initDaggerComponent()
}
fun getMyComponent(): APIComponent {
return apiComponent
}
fun initDaggerComponent():APIComponent{
apiComponent = DaggerAPIComponent
.builder()
.aPIModule(APIModule(APIURL.BASE_URL))
.build()
return apiComponent
} }
In the above code how to access the function getMyComponent() globally in Kotlin.

Put getMyComponen() inside companion like #Md. Asaduzzaman answer or use applicationContext to access it like -
(application as MyRetroApplication).getMyComponent()
or
(applicationContext as MyRetroApplication).getMyComponent()
or
MyRetroApplication.ctx?.let{
(it as MyRetroApplication).getMyComponent() //by your companion app context
}

Approach-1:
Put getMyComponent() inside companion
companion object {
var ctx: Context? = null
private lateinit var apiComponent: APIComponent
fun getMyComponent(): APIComponent = apiComponent
}
And then from anywhere:
MyRetroApplication.getMyComponent()
Approach-2:
Change the type of ctx to MyRetroApplication instead of Context and then from anywhere:
MyRetroApplication.ctx.getMyComponent()
Approach-3:
Same as approach 2 but in a formal way. Create getInstance() inside companion and pass ctx (private)
companion object {
private lateinit var ctx: MyRetroApplication
fun getInstance(): MyRetroApplication {
return ctx
}
}
And then from anywhere:
MyRetroApplication.getInstance().getMyComponent()

Kotlin singleton application class

On Android I want to make my application class a singleton.
Making it like this:
object MyApplication: Application(){}
won't work. The following error is thrown at runtime:
java.lang.IllegalAccessException: private com....is not accessible from class android.app.Instrumentation.
Doing this is also not possible:
class MyApp: Application() {
private val instance_: MyApp
init{
instance_ = this
}
override fun onCreate() {
super.onCreate()
if (BuildConfig.DEBUG) {
Timber.plant(Timber.DebugTree());
}
}
companion object{
fun getInstance() = instance_
}
}
How can I get an instance of my application class everywhere in my app? I would like to use MyApp.instance() instead of (applicationContext as MyApp).
Also an explanation why I want this: I have classes in my app. For example, a SharedPreference Singleton which is initialised with a context, and as it’s a singleton, it can't have arguments.

You can do the same thing you would do in Java, i.e. put the Application instance in a static field. Kotlin doesn't have static fields, but properties in objects are statically accessible.
class MyApp: Application() {
override fun onCreate() {
super.onCreate()
instance = this
}
companion object {
lateinit var instance: MyApp
private set
}
}
You can then access the property via MyApp.instance.

If you want to use it to access some static properties you have there: You will only have one instance of your Application, so simply use the name you gave to the class. Don't worry about it not being an actual singleton, you can use it the same way.
Example:
class MyApp : Application() {
companion object {
const val CONSTANT = 12
lateinit var typeface: Typeface
}
override fun onCreate() {
super.onCreate()
typeface = Typeface.createFromAsset(assets, "fonts/myFont.ttf")
}
}
Then you can use MyApp.CONSTANT and MyApp.typeface anywhere in your app.
-
If what you want is to use it as an application context you can create an extension property for Context:
val Context.myApp: MyApp
get() = applicationContext as MyApp
Then you can use myApp to get the the application context anywhere you have a context.

class AppController : Application() {
init {
instance = this
}
companion object {
private var instance: AppController? = null
fun applicationContext() : AppController {
return instance as AppController
}
}
override fun onCreate() {
super.onCreate()
}
}

You cannot do that because Android creates an Application instance using its parameterless constructor.
The problem you want to solve can be easily solved with DI. Just create instances with an injector so that the Context can be injected into objects as a dependency.