Fix ActivityTracker

Koin does not support nullable types

app/src/main/java/com/topjohnwu/magisk/App.kt

@@ -13,6 +13,7 @@ import androidx.work.impl.WorkDatabase
 import androidx.work.impl.WorkDatabase_Impl
 import com.topjohnwu.magisk.data.database.RepoDatabase
 import com.topjohnwu.magisk.data.database.RepoDatabase_Impl
+import com.topjohnwu.magisk.di.ActivityTracker
 import com.topjohnwu.magisk.di.koinModules
 import com.topjohnwu.magisk.extensions.get
 import com.topjohnwu.magisk.utils.LocaleManager
@@ -26,7 +27,7 @@ import java.util.concurrent.ThreadPoolExecutor
 
 open class App : Application() {
 
-    lateinit var protectedContext: Context
+    lateinit var deContext: Context
 
     override fun attachBaseContext(base: Context) {
         super.attachBaseContext(base)
@@ -39,15 +40,15 @@ open class App : Application() {
             modules(koinModules)
         }
 
-        protectedContext = baseContext
+        deContext = base
         self = this
 
         if (Build.VERSION.SDK_INT >= 24) {
-            protectedContext = base.createDeviceProtectedStorageContext()
-            protectedContext.moveSharedPreferencesFrom(base, base.defaultPrefsName)
+            deContext = base.createDeviceProtectedStorageContext()
+            deContext.moveSharedPreferencesFrom(base, defaultPrefsName)
         }
 
-        registerActivityLifecycleCallbacks(get())
+        registerActivityLifecycleCallbacks(get<ActivityTracker>())
 
         Networking.init(base)
         LocaleManager.setLocale(this)

app/src/main/java/com/topjohnwu/magisk/di/ApplicationModule.kt

@@ -1,5 +1,6 @@
 package com.topjohnwu.magisk.di
 
+import android.annotation.SuppressLint
 import android.app.Activity
 import android.app.Application
 import android.content.Context
@@ -14,15 +15,16 @@ val applicationModule = module {
     factory { get<Context>().resources }
     factory { get<Context>() as App }
     factory { get<Context>().packageManager }
-    factory(Protected) { get<App>().protectedContext }
+    factory(Protected) { get<App>().deContext }
     single(SUTimeout) { get<Context>(Protected).getSharedPreferences("su_timeout", 0) }
     single { PreferenceManager.getDefaultSharedPreferences(get<Context>(Protected)) }
-    single { ActivityTracker() as Application.ActivityLifecycleCallbacks }
-    factory { (get<Application.ActivityLifecycleCallbacks>() as ActivityTracker).foreground }
+    single { ActivityTracker() }
+    factory { get<ActivityTracker>().foreground ?: NullActivity }
 }
 
-private class ActivityTracker : Application.ActivityLifecycleCallbacks {
+class ActivityTracker : Application.ActivityLifecycleCallbacks {
 
+    @Volatile
     var foreground: Activity? = null
 
     override fun onActivityCreated(activity: Activity, bundle: Bundle?) {}
@@ -45,3 +47,6 @@ private class ActivityTracker : Application.ActivityLifecycleCallbacks {
 
     override fun onActivityDestroyed(activity: Activity) {}
 }
+
+@SuppressLint("Registered")
+object NullActivity : Activity()

app/src/main/java/com/topjohnwu/magisk/model/download/RemoteFileService.kt

@@ -7,6 +7,7 @@ import com.skoumal.teanity.extensions.subscribeK
 import com.topjohnwu.magisk.Config
 import com.topjohnwu.magisk.R
 import com.topjohnwu.magisk.data.network.GithubRawServices
+import com.topjohnwu.magisk.di.NullActivity
 import com.topjohnwu.magisk.extensions.firstMap
 import com.topjohnwu.magisk.extensions.get
 import com.topjohnwu.magisk.extensions.writeTo
@@ -56,7 +57,7 @@ abstract class RemoteFileService : NotificationService() {
             }
         }) {
             val newId = finishNotify(it, subject)
-            get<Activity?>()?.run {
+            if (get<Activity>() !is NullActivity) {
                 onFinished(it, subject, newId)
             }
         }