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How to pass context in Repository in MVVM without DI and following the clean architecture?

I need to initiate Room in its repository. But to do that I need context. If I pass context through the viewmodel i got this message This field leaks a context object.
I have checked this answer but they init the repository object in the view layer but according to the clean architecture view layer shouldnt know anything about data layer right? So how to organize the delivery of the context to the data layer without DI?
class MainViewModel(private val context: Context) : ViewModel() {
private val roomManager : RoomManager = RoomManagerImpl(context)
private fun addItem(){
roomManager.addItem()
}
}
Here is repository code
class RoomManagerImpl(private val context: Context) : RoomManager {
private val db = Room.databaseBuilder(
context,
AppDatabase::class.java, "database-name"
)

Passing Activity Context to the Activity's ViewModel is not a good practice it will cause memory leak.
You can get the context in your ViewModel by extending the AndroidViewModel class check below code.
It will give you application level context.
class MainViewModel(application: Application) : AndroidViewModel(application) {
private val context = getApplication<Application>().applicationContext
private val roomManager: RoomManager = RoomManagerImpl(context)
fun addItem() {
roomManager.addItem()
}
}

class MainViewModal(val repository:roomManager) :ViewModel() {
fun testFunction(context: Context){
roomManager.testMethod(context) //text method is your repository method
}
}
i am telling like this I hope it's help you otherwise you can use AndroidViewModel instead of Viewmodal

Android Kotlin: Having a global Context object for all activities (best practice)

I have a global app settings class as follows:
class AppSettings : MultiDexApplication() {
override fun onCreate() {
super.onCreate()
instance = this
resourses = applicationContext.resources
outputPathCache = cacheDir.absolutePath
}
companion object {
lateinit var instance: AppSettings
private set
val context: Context
get() { return activityContext.get()!! }
lateinit var activityContext: WeakReference<Context>
var database: SQLiteDatabase? = null
var resourses: Resources? = null
private set
lateinit var dialog: AlertDialog
const val defLanguage = Enum.Language.ENGLISH
const val defIdLanguage = Enum.LanguageId.ENGLISH
const val screenshotFilename = "xxx"
const val actionBarTitleColor = "#0D0D0D"
const val footerColor = "#8a8a8a"
const val activityBackground = "#ffffff"
... whatever
}
}
And as you see I have a static Context variable as follows:
lateinit var activityContext: WeakReference<Context>
(I use WeakReference so the IDE doesn't complain about memory leaks).
And I have a constant Context like the next:
val context: Context
get() { return activityContext.get()!! }
I assign a value for the first time to activityContext in SplashActivity as follows (I do this because the first activity is a OnBoarding class that doesn't inherit from BaseActivity):
AppSettings.activityContext = WeakReference(this)
The same in BaseActivity onCreate (most of my activities inherit from this class):
AppSettings.activityContext = WeakReference(this)
And then, in any activity which extends BaseActivity I can use the context simply like this:
AppSettings.context
For the activities that doesn't inherit from BaseActivity I just initialise the context to be used in the activity in the same way as in Base, so I can always get it as "AppSettings.context".
The reason of not simply using "this" in all activities to get context (or to use any sort of Context creation in Base) is that I'm using MVVM and there are classes outside activities (like ViewModel) with methods that may need a context, and I just don't wan't to pass it as a parameter (this is why I'm expecting to have a global context that can be accessed anywhere).
Although I have just finished and I haven't fully tested yet, it is apparently working great, but I wonder to know if this is the recommended way to deal with this, or if there is a better approach to have a global Context.

There are some ways to achieve that, but I believe the most encouraged by google is with the dependency injection library dagger-hilt, which isn't hard to set-up, but saves a lot of time and prevents possible memory-leaks.
In order to inject context into any class later you just need to do:
class ExampleClass #Inject constructor(#ApplicationContext val context: Context) {}

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.

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.