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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()

Access application context in companion object in kotlin

How can we access application context inside companion object in Android kotlin?
I have a companion object inside an abstract class and I want to access context to read Shared Preferences, but I'm not able to get the context.
UPDATE: I'm working with this stuff in an Android library and also the class that I'm working in is abstract

please see this go to link
class MainApplication : Application() {
init {
instance = this
}
companion object {
private var instance: MainApplication? = null
fun applicationContext() : Context {
return instance!!.applicationContext
}
}
override fun onCreate() {
super.onCreate()
// initialize for any
// Use ApplicationContext.
// example: SharedPreferences etc...
val context: Context = MainApplication.applicationContext()
}
}

Extends Application class like this
import android.app.Application
import android.content.Context
class MyApplication : Application() {
override fun onCreate() {
super.onCreate()
MyApplication.appContext = applicationContext
}
companion object {
lateinit var appContext: Context
}
}
then get context like this
val context = MyApplication.appContext

Actually I'm working inside an Android library and the class is abstract, so can't go with the already suggested solutions. However, I found way to do that.
Creat a lateinit Context field inside companion object.
abstract class MyClass {
companion object {
private lateinit var context: Context
fun setContext(con: Context) {
context=con
}
}
}
And then set it after the app has started
public class WelcomeActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_welcome);
MyClass.Companion.setContext(this);
}
}

There is a super cool article from the guys from Firebase explaining how their SDK gets hold of the context.
Basically my contentprovider looks like this:
/**
* This content provider is only responsible to inject the application context into the common module.
*/
class ContextProvider : ContentProvider() {
companion object {
private val TAG = ContextProvider::class.java.simpleName
}
override fun onCreate(): Boolean {
context?.let {
Common.setContext(it)
return true
}
Logger.e(TAG, "Context injection to common failed. Context is null! Check ContextProvider registration in the Manifest!")
return false
}
override fun query(uri: Uri, projection: Array<String>?, selection: String?, selectionArgs: Array<String>?, sortOrder: String?): Cursor? = null
override fun getType(uri: Uri): String? = null
override fun insert(uri: Uri, values: ContentValues?): Uri? = null
override fun delete(uri: Uri, selection: String?, selectionArgs: Array<String>?): Int = 0
override fun update(uri: Uri, values: ContentValues?, selection: String?, selectionArgs: Array<String>?): Int = 0
}
And the Common object, which I treat like an sibling of any Application class looks like this:
/**
* Partially working like an Application class by holding the appContext which makes it accessible inside this module.
*/
#SuppressLint("StaticFieldLeak")
object Common {
/**
* App appContext
*/
#Volatile
lateinit var appContext: Context
var isStoreVersion: Boolean = false
fun setContext(context: Context) {
appContext = context
}
}
As you can see I also enriched the Common object with a flag to store if the current build is a store version or not. Mainly because the BuildConfig of the app module is also not available in a module or library.
Don't forget to add the ContentProvider to the AndroidManifest of your library within the <application> tag
<provider android:name=".util.ContextProvider"
android:authorities="${applicationId}.common.util.contextprovider"
android:exported="false" />

You can save the instance directly inside a companion object and accessing it outside without problems, I think this approach is the simplest.
IMPORTANT: change the visibility of the instance property to private to ensure no one but Application has write access.
class App : Application() {
override fun onCreate() {
super.onCreate()
instance = this
}
companion object {
lateinit var instance: App
private set
}
}

class Test {
companion object {
lateinit var sharedPreferences: SharedPreferences
fun init(context: Context) {
// to prevent multiple initialization
if (!Companion::sharedPreferences.isInitialized) {
sharedPreferences = context.getSharedPreferences("preference_name", Context.MODE_PRIVATE)
}
}
}
}

How to assign same name Class variable in kotlin?

I want to assign my context in constructor but when I use "this" ide warn me. How can I write code like this Java code below, but in Kotlin:
here is java code
public class LoginApiService {
Context context;
public LoginApiService(Context context) {
this.context = context;
}
}
here is what I want to do
class YLAService {
var context:Context?=null
class YLAService constructor(context: Context) {
this.context=context
}
}

In Kotlin, if you provide a var or val in the constructor, it automatically becomes available as a property you can use. No other assignment is required.
class LoginApiService(val context: Context) {
// Example...
fun doSomething() {
context.doSomethingOnContext()
}
}

Static like methods in Android application with kotlin

I am trying to add a "static" method to my MyApplication class in kotlin
I have added (as a property) the variable :
private var context: Context? = null
in method:
override fun onCreate()
I added:
context = applicationContext
then I add a companion object like this
companion object {
#JvmStatic fun getMyApplicationContext(): Context?
{
return MyApplication().context
}
}
when I call this method from other parts of the application like
MyApplication.getMyApplicationContext() it always returns null. I have gleaned all this from several sources but I am not sure if it is anywhere near correct or not.

It sounds like you want a global application context object. Now casting aside my dislike for global variables, I think you are pretty close.
I think you just need to add the variable into the MyApplication classes companion object and use that directly. You only need the #JvmField annotation if you're going to access the field from Java.
class MyApplication {
companion object {
#JvmField
var context: Context? = null
// Not really needed since we can access the variable directly.
#JvmStatic fun getMyApplicationContext(): Context? {
return context
}
}
override fun onCreate() {
...
MyApplication.context = appContext
}
}