android: Add a preference flag to ignore battery optimizations

This allows users to ignore whether the app is on the device's power
whitelist without a warning.  The flag is currently not set
automatically if the user denies the request.

src/frontends/android/app/src/main/java/org/strongswan/android/ui/VpnProfileControlActivity.java

@@ -23,6 +23,7 @@ import android.content.Context;
 import android.content.DialogInterface;
 import android.content.Intent;
 import android.content.ServiceConnection;
+import android.content.SharedPreferences;
 import android.net.Uri;
 import android.net.VpnService;
 import android.os.Build;
@@ -41,6 +42,7 @@ import org.strongswan.android.data.VpnProfileDataSource;
 import org.strongswan.android.data.VpnType.VpnTypeFeature;
 import org.strongswan.android.logic.VpnStateService;
 import org.strongswan.android.logic.VpnStateService.State;
+import org.strongswan.android.utils.Constants;
 
 import androidx.annotation.NonNull;
 import androidx.appcompat.app.AlertDialog;
@@ -49,6 +51,7 @@ import androidx.appcompat.app.AppCompatDialogFragment;
 import androidx.fragment.app.Fragment;
 import androidx.fragment.app.FragmentManager;
 import androidx.fragment.app.FragmentTransaction;
+import androidx.preference.PreferenceManager;
 
 public class VpnProfileControlActivity extends AppCompatActivity
 {
@@ -198,7 +201,9 @@ public class VpnProfileControlActivity extends AppCompatActivity
 		if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M)
 		{
 			PowerManager pm = (PowerManager)this.getSystemService(Context.POWER_SERVICE);
-			if (!pm.isIgnoringBatteryOptimizations(this.getPackageName()))
+			SharedPreferences pref = PreferenceManager.getDefaultSharedPreferences(this);
+			if (!pm.isIgnoringBatteryOptimizations(this.getPackageName()) &&
+				!pref.getBoolean(Constants.PREF_IGNORE_POWER_WHITELIST, false))
 			{
 				PowerWhitelistRequired whitelist = new PowerWhitelistRequired();
 				mWaitingForResult = true;

src/frontends/android/app/src/main/java/org/strongswan/android/utils/Constants.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2016-2018 Tobias Brunner
+ * Copyright (C) 2016-2020 Tobias Brunner
  * HSR Hochschule fuer Technik Rapperswil
  *
  * This program is free software; you can redistribute it and/or modify it
@@ -58,4 +58,9 @@ public final class Constants
 	 * Preference key to store the most recently used VPN profile
 	 */
 	public static final String PREF_MRU_VPN_PROFILE = "pref_mru_vpn_profile";
+
+	/**
+	 * Preference key to store whether the user permanently dismissed our warning to add the app to the power whitelist
+	 */
+	public static final String PREF_IGNORE_POWER_WHITELIST = "pref_ignore_power_whitelist";
 }

src/frontends/android/app/src/main/res/values-de/strings.xml

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!--
-    Copyright (C) 2012-2019 Tobias Brunner
+    Copyright (C) 2012-2020 Tobias Brunner
     Copyright (C) 2012 Giuliano Grassi
     Copyright (C) 2012 Ralf Sager
     HSR Hochschule fuer Technik Rapperswil
@@ -36,6 +36,8 @@
     <string name="pref_title">Einstellungen</string>
     <string name="pref_default_vpn_profile">Voreingestelltes VPN Profil</string>
     <string name="pref_default_vpn_profile_mru">Verbinden mit zuletzt verwendetem Profil</string>
+    <string name="pref_power_whitelist_title">Akku-Optimierung ignorieren</string>
+    <string name="pref_power_whitelist_summary">Keine Warnung anzeigen, falls die App nicht auf der weissen Liste für Akku-Optimierung ist</string>
 
     <!-- Log view -->
     <string name="log_title">Log</string>

src/frontends/android/app/src/main/res/values-pl/strings.xml

@@ -36,6 +36,8 @@
     <string name="pref_title">Settings</string>
     <string name="pref_default_vpn_profile">Default VPN profile</string>
     <string name="pref_default_vpn_profile_mru">Connect to most recently used profile</string>
+    <string name="pref_power_whitelist_title">Ignore battery optimizations</string>
+    <string name="pref_power_whitelist_summary">Don\'t show a warning if the app is not on the device\'s power whitelist</string>
 
     <!-- Log view -->
     <string name="log_title">Log</string>

src/frontends/android/app/src/main/res/values-ru/strings.xml

@@ -33,6 +33,8 @@
     <string name="pref_title">Settings</string>
     <string name="pref_default_vpn_profile">Default VPN profile</string>
     <string name="pref_default_vpn_profile_mru">Connect to most recently used profile</string>
+    <string name="pref_power_whitelist_title">Ignore battery optimizations</string>
+    <string name="pref_power_whitelist_summary">Don\'t show a warning if the app is not on the device\'s power whitelist</string>
 
     <!-- Log view -->
     <string name="log_title">Журнал</string>

src/frontends/android/app/src/main/res/values-ua/strings.xml

@@ -34,6 +34,8 @@
     <string name="pref_title">Settings</string>
     <string name="pref_default_vpn_profile">Default VPN profile</string>
     <string name="pref_default_vpn_profile_mru">Connect to most recently used profile</string>
+    <string name="pref_power_whitelist_title">Ignore battery optimizations</string>
+    <string name="pref_power_whitelist_summary">Don\'t show a warning if the app is not on the device\'s power whitelist</string>
 
     <!-- Log view -->
     <string name="log_title">Журнал</string>

src/frontends/android/app/src/main/res/values-zh-rCN/strings.xml

@@ -33,6 +33,8 @@
     <string name="pref_title">Settings</string>
     <string name="pref_default_vpn_profile">Default VPN profile</string>
     <string name="pref_default_vpn_profile_mru">Connect to most recently used profile</string>
+    <string name="pref_power_whitelist_title">Ignore battery optimizations</string>
+    <string name="pref_power_whitelist_summary">Don\'t show a warning if the app is not on the device\'s power whitelist</string>
 
     <!-- Log view -->
     <string name="log_title">日志</string>

src/frontends/android/app/src/main/res/values-zh-rTW/strings.xml

@@ -33,6 +33,8 @@
     <string name="pref_title">Settings</string>
     <string name="pref_default_vpn_profile">Default VPN profile</string>
     <string name="pref_default_vpn_profile_mru">Connect to most recently used profile</string>
+    <string name="pref_power_whitelist_title">Ignore battery optimizations</string>
+    <string name="pref_power_whitelist_summary">Don\'t show a warning if the app is not on the device\'s power whitelist</string>
 
     <!-- Log view -->
     <string name="log_title">日誌</string>

src/frontends/android/app/src/main/res/values/strings.xml

@@ -36,6 +36,8 @@
     <string name="pref_title">Settings</string>
     <string name="pref_default_vpn_profile">Default VPN profile</string>
     <string name="pref_default_vpn_profile_mru">Connect to most recently used profile</string>
+    <string name="pref_power_whitelist_title">Ignore battery optimizations</string>
+    <string name="pref_power_whitelist_summary">Don\'t show a warning if the app is not on the device\'s power whitelist</string>
 
     <!-- Log view -->
     <string name="log_title">Log</string>

src/frontends/android/app/src/main/res/xml/settings.xml

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!--
-    Copyright (C) 2018 Tobias Brunner
+    Copyright (C) 2018-2020 Tobias Brunner
     HSR Hochschule fuer Technik Rapperswil
 
     This program is free software; you can redistribute it and/or modify it
@@ -20,4 +20,9 @@
         android:title="@string/pref_default_vpn_profile"
         android:summary="@string/pref_default_vpn_profile_mru" />
 
+    <SwitchPreference
+        android:key="pref_ignore_power_whitelist"
+        android:title="@string/pref_power_whitelist_title"
+        android:summary="@string/pref_power_whitelist_summary" />
+
 </PreferenceScreen>