Native android service implemented

client/android/src/org/amnezia/vpn/qt/VPNPermissionHelper.kt

@@ -0,0 +1,37 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.amnezia.vpn.qt
+
+import android.content.Context
+import android.content.Intent
+
+class VPNPermissionHelper : android.net.VpnService() {
+    /**
+     * This small service does nothing else then checking if the vpn permission
+     * is present and prompting if not.
+     */
+    override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
+        val intent = prepare(this.applicationContext)
+        if (intent != null) {
+            startActivityForResult(intent)
+        }
+        return START_NOT_STICKY
+    }
+
+    companion object {
+        @JvmStatic
+        fun startService(c: Context) {
+            val appC = c.applicationContext
+            appC.startService(Intent(appC, VPNPermissionHelper::class.java))
+        }
+    }
+
+    /**
+     * Fetches the Global QTAndroidActivity and calls startActivityForResult with the given intent
+     * Is used to request the VPN-Permission, if not given.
+     * Actually Implemented in src/platforms/android/AndroidController.cpp
+     */
+    external fun startActivityForResult(i: Intent)
+}