Converted activity to kt code & improved custom context syntax

Author: cioccarellia

app/build.gradle

@@ -25,6 +25,7 @@ dependencies {
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
     implementation 'com.android.support:appcompat-v7:28.0.0'
     implementation 'com.android.support.constraint:constraint-layout:1.1.3'
+    implementation "org.jetbrains.kotlinx:kotlinx-coroutines-android:1.3.2"
     implementation 'com.android.support:design:28.0.0'
     implementation "com.android.support:support-v4:28.0.0"
     implementation project(path: ':library')

app/src/main/java/com/andreacioccarelli/billingprotectorsample/DetectionActivity.java

@@ -0,0 +1,56 @@
+package com.andreacioccarelli.billingprotectorsample
+
+import android.annotation.SuppressLint
+import android.os.Bundle
+import android.app.Activity
+import android.content.Context
+import android.os.Vibrator
+import android.support.design.widget.FloatingActionButton
+import android.widget.TextView
+import android.widget.Toast
+
+import com.andreacioccarelli.billingprotector.*
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.launch
+import java.util.concurrent.TimeUnit
+import kotlin.coroutines.CoroutineContext
+import kotlin.system.measureTimeMillis
+
+class DetectionActivity : Activity() {
+
+    private lateinit var bp: BillingProtector
+
+    @SuppressLint("SetTextI18n")
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setContentView(R.layout.activity)
+
+        bp = BillingProtector(this)
+        runRefresh()
+
+        val fab = findViewById<FloatingActionButton>(R.id.fab)
+        fab.setOnClickListener {
+            val vib = getSystemService(Context.VIBRATOR_SERVICE) as Vibrator
+            vib.vibrate(100)
+
+            runRefresh()
+        }
+    }
+
+    private fun runRefresh() = CoroutineScope(Dispatchers.Main).launch {
+        val millis = measureTimeMillis {  updateData() }
+        val seconds = TimeUnit.MILLISECONDS.toSeconds(millis)
+
+        runOnUiThread {
+            Toast.makeText(this@DetectionActivity, "Re-computed. time: ${seconds}s", Toast.LENGTH_SHORT).show()
+        }
+    }
+
+    private var i = 0
+    @SuppressLint("SetTextI18n")
+    private suspend fun updateData() {
+        val mxp = findViewById<TextView>(R.id.mxp)
+        mxp.text = "i=${i++}\nisRootInstalled: ${bp.isRootInstalled()}\npirateAppsList: ${bp.getPirateAppsListAsync()}"
+    }
+}

app/src/main/java/com/andreacioccarelli/billingprotectorsample/DetectionActivity.kt

@@ -14,7 +14,7 @@
 
         <android.support.v7.widget.Toolbar
             android:id="@+id/toolbar"
-            app:title="Java activity"
+            app:title="Kt activity"
             android:layout_width="match_parent"
             android:layout_height="?attr/actionBarSize"
             android:background="?attr/colorPrimary"

app/src/main/res/layout/activity.xml

@@ -9,6 +9,7 @@ import com.andreacioccarelli.billingprotector.data.PirateApp
 import com.andreacioccarelli.billingprotector.data.SelectionCriteria
 import com.andreacioccarelli.billingprotector.utils.RootUtils
 import com.andreacioccarelli.billingprotector.utils.assembleAppList
+import kotlinx.coroutines.CoroutineDispatcher
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.withContext
@@ -18,7 +19,8 @@ import kotlinx.coroutines.withContext
  */
 class BillingProtector(
     private val context: Context,
-    private val simulateSafeEnvironment: Boolean = false
+    private val simulateSafeEnvironment: Boolean = false,
+    private val coroutineContext: CoroutineDispatcher = Dispatchers.Default
 ) {
     /**
      * Lazily-evaluated and statically-generated pirate apps list
@@ -49,7 +51,7 @@ class BillingProtector(
      * */
     suspend fun getPirateAppsListAsync(): List<PirateApp> {
         if (simulateSafeEnvironment) return emptyList()
-        return withContext(CoroutineScope(Dispatchers.Default).coroutineContext) { startScan() }
+        return withContext(coroutineContext) { startScan() }
     }
 
     /**