update to sdk 29, migrate to androidx, new GUI

28 files changed, 723 insertions, 241 deletions

diff --git a/.gitignore b/.gitignore
index fd45b12..603b140 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,11 +1,14 @@
 *.iml
 .gradle
 /local.properties
-/.idea/caches/build_file_checksums.ser
+/.idea/caches
 /.idea/libraries
 /.idea/modules.xml
 /.idea/workspace.xml
+/.idea/navEditor.xml
+/.idea/assetWizardSettings.xml
 .DS_Store
 /build
 /captures
 .externalNativeBuild
+.cxx
diff --git a/.idea/codeStyles/Project.xml b/.idea/codeStyles/Project.xml
new file mode 100644
index 0000000..681f41a
--- /dev/null
+++ b/.idea/codeStyles/Project.xml
@@ -0,0 +1,116 @@
+<component name="ProjectCodeStyleConfiguration">
+  <code_scheme name="Project" version="173">
+    <codeStyleSettings language="XML">
+      <indentOptions>
+        <option name="CONTINUATION_INDENT_SIZE" value="4" />
+      </indentOptions>
+      <arrangement>
+        <rules>
+          <section>
+            <rule>
+              <match>
+                <AND>
+                  <NAME>xmlns:android</NAME>
+                  <XML_ATTRIBUTE />
+                  <XML_NAMESPACE>^$</XML_NAMESPACE>
+                </AND>
+              </match>
+            </rule>
+          </section>
+          <section>
+            <rule>
+              <match>
+                <AND>
+                  <NAME>xmlns:.*</NAME>
+                  <XML_ATTRIBUTE />
+                  <XML_NAMESPACE>^$</XML_NAMESPACE>
+                </AND>
+              </match>
+              <order>BY_NAME</order>
+            </rule>
+          </section>
+          <section>
+            <rule>
+              <match>
+                <AND>
+                  <NAME>.*:id</NAME>
+                  <XML_ATTRIBUTE />
+                  <XML_NAMESPACE>http://schemas.android.com/apk/res/android</XML_NAMESPACE>
+                </AND>
+              </match>
+            </rule>
+          </section>
+          <section>
+            <rule>
+              <match>
+                <AND>
+                  <NAME>.*:name</NAME>
+                  <XML_ATTRIBUTE />
+                  <XML_NAMESPACE>http://schemas.android.com/apk/res/android</XML_NAMESPACE>
+                </AND>
+              </match>
+            </rule>
+          </section>
+          <section>
+            <rule>
+              <match>
+                <AND>
+                  <NAME>name</NAME>
+                  <XML_ATTRIBUTE />
+                  <XML_NAMESPACE>^$</XML_NAMESPACE>
+                </AND>
+              </match>
+            </rule>
+          </section>
+          <section>
+            <rule>
+              <match>
+                <AND>
+                  <NAME>style</NAME>
+                  <XML_ATTRIBUTE />
+                  <XML_NAMESPACE>^$</XML_NAMESPACE>
+                </AND>
+              </match>
+            </rule>
+          </section>
+          <section>
+            <rule>
+              <match>
+                <AND>
+                  <NAME>.*</NAME>
+                  <XML_ATTRIBUTE />
+                  <XML_NAMESPACE>^$</XML_NAMESPACE>
+                </AND>
+              </match>
+              <order>BY_NAME</order>
+            </rule>
+          </section>
+          <section>
+            <rule>
+              <match>
+                <AND>
+                  <NAME>.*</NAME>
+                  <XML_ATTRIBUTE />
+                  <XML_NAMESPACE>http://schemas.android.com/apk/res/android</XML_NAMESPACE>
+                </AND>
+              </match>
+              <order>ANDROID_ATTRIBUTE_ORDER</order>
+            </rule>
+          </section>
+          <section>
+            <rule>
+              <match>
+                <AND>
+                  <NAME>.*</NAME>
+                  <XML_ATTRIBUTE />
+                  <XML_NAMESPACE>.*</XML_NAMESPACE>
+                </AND>
+              </match>
+              <order>BY_NAME</order>
+            </rule>
+          </section>
+        </rules>
+      </arrangement>
+    </codeStyleSettings>
+  </code_scheme>
+</component>
\ No newline at end of file
diff --git a/.idea/gradle.xml b/.idea/gradle.xml
new file mode 100644
index 0000000..d291b3d
--- /dev/null
+++ b/.idea/gradle.xml
@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="GradleSettings">
+    <option name="linkedExternalProjectsSettings">
+      <GradleProjectSettings>
+        <compositeConfiguration>
+          <compositeBuild compositeDefinitionSource="SCRIPT" />
+        </compositeConfiguration>
+        <option name="distributionType" value="DEFAULT_WRAPPED" />
+        <option name="externalProjectPath" value="$PROJECT_DIR$" />
+        <option name="resolveModulePerSourceSet" value="false" />
+        <option name="testRunner" value="PLATFORM" />
+      </GradleProjectSettings>
+    </option>
+  </component>
+</project>
\ No newline at end of file
diff --git a/.idea/misc.xml b/.idea/misc.xml
new file mode 100644
index 0000000..37a7509
--- /dev/null
+++ b/.idea/misc.xml
@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_1_7" project-jdk-name="1.8" project-jdk-type="JavaSDK">
+    <output url="file://$PROJECT_DIR$/build/classes" />
+  </component>
+  <component name="ProjectType">
+    <option name="id" value="Android" />
+  </component>
+</project>
\ No newline at end of file
diff --git a/.idea/runConfigurations.xml b/.idea/runConfigurations.xml
new file mode 100644
index 0000000..7f68460
--- /dev/null
+++ b/.idea/runConfigurations.xml
@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="RunConfigurationProducerService">
+    <option name="ignoredProducers">
+      <set>
+        <option value="org.jetbrains.plugins.gradle.execution.test.runner.AllInPackageGradleConfigurationProducer" />
+        <option value="org.jetbrains.plugins.gradle.execution.test.runner.TestClassGradleConfigurationProducer" />
+        <option value="org.jetbrains.plugins.gradle.execution.test.runner.TestMethodGradleConfigurationProducer" />
+      </set>
+    </option>
+  </component>
+</project>
\ No newline at end of file
diff --git a/.idea/vcs.xml b/.idea/vcs.xml
new file mode 100644
index 0000000..35eb1dd
--- /dev/null
+++ b/.idea/vcs.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="" vcs="Git" />
+  </component>
+</project>
\ No newline at end of file
diff --git a/app/build.gradle b/app/build.gradle
index 523c8a4..e13abab 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -1,14 +1,14 @@
 apply plugin: 'com.android.application'
 
 android {
-    compileSdkVersion 28
+    compileSdkVersion 29
     defaultConfig {
         applicationId "com.javispedro.vndroid"
         minSdkVersion 26
-        targetSdkVersion 28
+        targetSdkVersion 29
         versionCode 1
         versionName "1.0"
-        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
+        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
         ndk {
             //abiFilters 'x86'
         }
@@ -34,11 +34,9 @@ android {
 }
 
 dependencies {
-    implementation fileTree(include: ['*.jar'], dir: 'libs')
-    implementation 'com.android.support:appcompat-v7:28.0.0'
-    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
-    implementation 'com.android.support:support-v4:28.0.0'
-    testImplementation 'junit:junit:4.12'
-    androidTestImplementation 'com.android.support.test:runner:1.0.2'
-    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
+    implementation fileTree(dir: 'libs', include: ['*.jar'])
+    implementation 'androidx.appcompat:appcompat:1.0.2'
+    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
+    implementation 'com.google.android.material:material:1.0.0'
+    implementation 'androidx.preference:preference:1.1.0-alpha05'
 }
diff --git a/app/libs/.gitignore b/app/libs/.gitignore
new file mode 100644
index 0000000..b48c09f
--- /dev/null
+++ b/app/libs/.gitignore
@@ -0,0 +1,3 @@
+libjpeg-turbo*
+libvncserver*
+openssl*
diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index 5786f0f..2ad6c82 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -12,7 +12,10 @@
         android:roundIcon="@mipmap/ic_launcher_round"
         android:supportsRtl="true"
         android:theme="@style/AppTheme">
-        <activity android:name=".SetupActivity">
+
+        <activity
+            android:name=".SettingsActivity"
+            android:label="@string/app_name">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
                 <category android:name="android.intent.category.LAUNCHER" />
@@ -22,8 +25,8 @@
         <service
             android:name=".ServerService"
             android:enabled="true"
-            android:exported="true" />
-
+            android:exported="true"
+            android:foregroundServiceType="mediaProjection" />
         <service
             android:name=".ControlService"
             android:permission="android.permission.BIND_ACCESSIBILITY_SERVICE">
@@ -35,7 +38,6 @@
                 android:name="android.accessibilityservice"
                 android:resource="@xml/controlservice" />
         </service>
-
     </application>
 
 </manifest>
\ No newline at end of file
diff --git a/app/src/main/cpp/native-lib.cpp b/app/src/main/cpp/native-lib.cpp
index 3a1811c..6216181 100644
--- a/app/src/main/cpp/native-lib.cpp
+++ b/app/src/main/cpp/native-lib.cpp
@@ -41,6 +41,7 @@ struct Data
     jobject cb_obj;
     jmethodID cb_ev_ptr;
     jmethodID cb_ev_key;
+    jmethodID cb_ev_client;
 
     std::atomic<bool> pendingPtrEvent;
     int ptrButtonMask, ptrX, ptrY;
@@ -48,6 +49,10 @@ struct Data
     std::atomic<bool> pendingKeyEvent;
     rfbKeySym key;
     bool keyState;
+
+    std::atomic<bool> pendingClientEvent;
+
+    unsigned int numClients;
 };
 
 static inline Data * getData(JNIEnv *env, jobject instance)
@@ -71,6 +76,16 @@ static inline Data * getData(rfbClientPtr client)
     return data;
 }
 
+static void listen_thread_client_gone(rfbClientPtr client)
+{
+    Data *data = getData(client);
+
+    data->numClients--;
+    data->pendingClientEvent = true;
+
+    eventfd_write(data->eventEventFd, 1);
+}
+
 static void listen_thread_main(Data *data, JavaVM *vm)
 {
     rfbScreenInfoPtr screen = data->screen;
@@ -104,11 +119,20 @@ static void listen_thread_main(Data *data, JavaVM *vm)
         else if (data->listenEventFd >= 0 && FD_ISSET(data->listenEventFd, &listen_fds))
             break;
 
-        rfbClientPtr cl = NULL;
-        if(client_fd >= 0)
-            cl = rfbNewClient(screen,client_fd);
-        if (cl && !cl->onHold )
-            rfbStartOnHoldClient(cl);
+        if(client_fd >= 0) {
+            rfbClientPtr cl = rfbNewClient(screen, client_fd);
+            if (cl) {
+                cl->clientGoneHook = listen_thread_client_gone;
+
+                data->numClients++;
+                data->pendingClientEvent = true;
+
+                eventfd_write(data->eventEventFd, 1);
+
+                if (!cl->onHold)
+                    rfbStartOnHoldClient(cl);
+            }
+        }
     }
 }
 
@@ -134,6 +158,11 @@ static void event_thread_main(Data *data, JavaVM *vm)
             env->CallVoidMethod(data->cb_obj, data->cb_ev_key, (jint)data->key, (jboolean)data->keyState);
             data->pendingKeyEvent = false;
         }
+
+        if (data->pendingClientEvent) {
+            env->CallVoidMethod(data->cb_obj, data->cb_ev_client);
+            data->pendingClientEvent = false;
+        }
     }
 
     vm->DetachCurrentThread();
@@ -150,6 +179,7 @@ static void ptr_event(int buttonMask, int x, int y, rfbClientPtr cl)
 
     eventfd_write(data->eventEventFd, 1);
 
+    // Still send the event to RFB, to do server-side cursor processing
     rfbDefaultPtrAddEvent(buttonMask, x, y, cl);
 }
 
@@ -199,10 +229,13 @@ Java_com_javispedro_vndroid_RFBServer_allocate(JNIEnv *env, jobject instance)
     assert(data->cb_ev_ptr);
     data->cb_ev_key = env->GetMethodID(cb_cls, "onKeyEvent", "(IZ)V");
     assert(data->cb_ev_key);
+    data->cb_ev_client = env->GetMethodID(cb_cls, "onClientEvent", "()V");
+    assert(data->cb_ev_client);
 
     data->screen = 0;
     data->listenEventFd = -1;
     data->eventEventFd = -1;
+    data->numClients = 0;
 
     env->SetLongField(instance, fid, reinterpret_cast<jlong>(data));
 
@@ -359,3 +392,10 @@ Java_com_javispedro_vndroid_RFBServer_put_1image(JNIEnv *env, jobject instance,
 
     return JNI_TRUE;
 }
+
+extern "C"
+JNIEXPORT jint JNICALL
+Java_com_javispedro_vndroid_RFBServer_get_1num_1clients(JNIEnv *env, jobject instance) {
+    Data *data = getData(env, instance);
+    return data->numClients;
+}
\ No newline at end of file
diff --git a/app/src/main/java/com/javispedro/vndroid/ControlService.java b/app/src/main/java/com/javispedro/vndroid/ControlService.java
index db5362d..166e379 100644
--- a/app/src/main/java/com/javispedro/vndroid/ControlService.java
+++ b/app/src/main/java/com/javispedro/vndroid/ControlService.java
@@ -2,10 +2,11 @@ package com.javispedro.vndroid;
 
 import android.accessibilityservice.AccessibilityService;
 import android.content.Intent;
-import android.support.annotation.Nullable;
 import android.util.Log;
 import android.view.accessibility.AccessibilityEvent;
 
+import androidx.annotation.Nullable;
+
 public class ControlService extends AccessibilityService {
     private final String TAG = ControlService.class.getSimpleName();
 
diff --git a/app/src/main/java/com/javispedro/vndroid/KeyEventOutput.java b/app/src/main/java/com/javispedro/vndroid/KeyEventOutput.java
index 597942a..3ec4319 100644
--- a/app/src/main/java/com/javispedro/vndroid/KeyEventOutput.java
+++ b/app/src/main/java/com/javispedro/vndroid/KeyEventOutput.java
@@ -1,10 +1,11 @@
 package com.javispedro.vndroid;
 
 import android.os.Bundle;
-import android.support.annotation.Nullable;
 import android.util.Log;
 import android.view.accessibility.AccessibilityNodeInfo;
 
+import androidx.annotation.Nullable;
+
 import com.javispedro.vndroid.keymaps.KeyActionHandler;
 import com.javispedro.vndroid.keymaps.KeyHandler;
 
diff --git a/app/src/main/java/com/javispedro/vndroid/RFBServer.java b/app/src/main/java/com/javispedro/vndroid/RFBServer.java
index f5af05c..8838818 100644
--- a/app/src/main/java/com/javispedro/vndroid/RFBServer.java
+++ b/app/src/main/java/com/javispedro/vndroid/RFBServer.java
@@ -2,8 +2,8 @@ package com.javispedro.vndroid;
 
 import android.graphics.PixelFormat;
 import android.media.Image;
-import android.support.annotation.Nullable;
-import android.util.EventLog;
+
+import androidx.annotation.Nullable;
 
 import java.nio.ByteBuffer;
 
@@ -25,6 +25,7 @@ public class RFBServer {
     public interface EventCallback {
         void onPointerEvent(int buttonMask, int x, int y);
         void onKeyEvent(int key, boolean state);
+        void onClientEvent();
     }
 
     public RFBServer() {
@@ -40,13 +41,13 @@ public class RFBServer {
     }
 
     public void stop() {
-        forgetLastImage();
         shutdown();
+        forgetLastImage();
     }
 
     public void finalize() {
-        forgetLastImage();
         shutdown();
+        forgetLastImage();
         deallocate();
     }
 
@@ -77,6 +78,10 @@ public class RFBServer {
         lastImage = image;
     }
 
+    public int getNumClients() {
+        return get_num_clients();
+    }
+
     private void forgetLastImage() {
         if (lastImage != null) {
             lastImage.close();
@@ -95,4 +100,6 @@ public class RFBServer {
     private native void set_event_callback(EventCallback c);
 
     private native boolean put_image(int width, int height, ByteBuffer buffer, int pixel_stride, int row_stride);
+
+    private native int get_num_clients();
 }
diff --git a/app/src/main/java/com/javispedro/vndroid/ScreenGrabber.java b/app/src/main/java/com/javispedro/vndroid/ScreenGrabber.java
index 54d11bc..a5701b3 100644
--- a/app/src/main/java/com/javispedro/vndroid/ScreenGrabber.java
+++ b/app/src/main/java/com/javispedro/vndroid/ScreenGrabber.java
@@ -5,9 +5,10 @@ import android.content.ContextWrapper;
 import android.hardware.display.VirtualDisplay;
 import android.media.Image;
 import android.media.ImageReader;
-import android.support.annotation.Nullable;
 import android.util.Log;
 
+import androidx.annotation.Nullable;
+
 public abstract class ScreenGrabber extends ContextWrapper {
     private static final String TAG = ScreenGrabber.class.getSimpleName();
 
diff --git a/app/src/main/java/com/javispedro/vndroid/ScreenMirrorGrabber.java b/app/src/main/java/com/javispedro/vndroid/ScreenMirrorGrabber.java
index 9f78b3c..c223c65 100644
--- a/app/src/main/java/com/javispedro/vndroid/ScreenMirrorGrabber.java
+++ b/app/src/main/java/com/javispedro/vndroid/ScreenMirrorGrabber.java
@@ -1,34 +1,50 @@
 package com.javispedro.vndroid;
 
+import android.app.Activity;
 import android.content.Context;
+import android.content.Intent;
 import android.graphics.PixelFormat;
 import android.hardware.display.DisplayManager;
 import android.media.ImageReader;
 import android.media.projection.MediaProjection;
+import android.media.projection.MediaProjectionManager;
 import android.os.Handler;
-import android.support.annotation.NonNull;
 import android.util.DisplayMetrics;
 import android.util.Log;
 import android.view.Display;
+import android.view.WindowManager;
 
 public class ScreenMirrorGrabber extends ScreenGrabber {
     private static final String TAG = ScreenMirrorGrabber.class.getSimpleName();
 
-    protected final MediaProjection projection;
-    protected final Display realDisplay;
+    protected MediaProjection projection;
 
-    protected final DisplayMetrics realDisplayMetrics;
+    protected int projAskCode;
+    protected Intent projAskData;
+
+    protected Display realDisplay;
+    protected DisplayMetrics realDisplayMetrics;
 
     private float scale = 0.5f;
 
-    public ScreenMirrorGrabber(Context context, @NonNull MediaProjection proj, @NonNull Display display) {
+    public ScreenMirrorGrabber(Context context, MediaProjection proj) {
         super(context);
         projection = proj;
-        realDisplay = display;
-        realDisplayMetrics = new DisplayMetrics();
+        projAskCode = 0;
+        projAskData = null; // Already obtained
+    }
+
+    public ScreenMirrorGrabber(Context context, int projectionResultCode, Intent projectionResultData) {
+        super(context);
+        projection = null;
+        projAskCode = projectionResultCode;
+        projAskData = projectionResultData;
     }
 
     private void initDisplay() {
+        WindowManager wm = getSystemService(WindowManager.class);
+        realDisplay = wm.getDefaultDisplay();
+        realDisplayMetrics = new DisplayMetrics();
         realDisplay.getRealMetrics(realDisplayMetrics);
 
         Log.d(TAG, "real display size: " + realDisplayMetrics.widthPixels + "x" + realDisplayMetrics.heightPixels);
@@ -55,6 +71,12 @@ public class ScreenMirrorGrabber extends ScreenGrabber {
             Log.w(TAG, "already started");
             return;
         }
+        if (projection == null && projAskCode == Activity.RESULT_OK) {
+            MediaProjectionManager manager = getSystemService(MediaProjectionManager.class);
+            projection = manager.getMediaProjection(projAskCode, projAskData);
+            projAskCode = 0;
+            projAskData = null;
+        }
 
         initDisplay();
     }
diff --git a/app/src/main/java/com/javispedro/vndroid/ServerRunningNotification.java b/app/src/main/java/com/javispedro/vndroid/ServerRunningNotification.java
index 6fcf8ab..224df0e 100644
--- a/app/src/main/java/com/javispedro/vndroid/ServerRunningNotification.java
+++ b/app/src/main/java/com/javispedro/vndroid/ServerRunningNotification.java
@@ -1,6 +1,5 @@
 package com.javispedro.vndroid;
 
-import android.annotation.TargetApi;
 import android.app.Notification;
 import android.app.NotificationChannel;
 import android.app.NotificationManager;
@@ -8,11 +7,8 @@ import android.app.PendingIntent;
 import android.content.Context;
 import android.content.Intent;
 import android.content.res.Resources;
-import android.graphics.Bitmap;
-import android.graphics.BitmapFactory;
-import android.net.Uri;
-import android.os.Build;
-import android.support.v4.app.NotificationCompat;
+
+import androidx.core.app.NotificationCompat;
 
 /**
  * Helper class for showing and canceling server running
@@ -86,7 +82,7 @@ public class ServerRunningNotification {
                         PendingIntent.getActivity(
                                 context,
                                 0,
-                                new Intent(context, SetupActivity.class),
+                                new Intent(context, SettingsActivity.class),
                                 PendingIntent.FLAG_UPDATE_CURRENT))
 
                 // Example additional actions for this notification. These will
@@ -100,7 +96,7 @@ public class ServerRunningNotification {
                         PendingIntent.getForegroundService(
                                 context,
                                 0,
-                                new Intent(context, ServerService.class).setAction(ServerService.ACTION_STOP),
+                                new Intent(context, ServerService.class).setAction(ServerService.ACTION_STOP_SERVER),
                                 PendingIntent.FLAG_UPDATE_CURRENT));
 
         return builder.build();
diff --git a/app/src/main/java/com/javispedro/vndroid/ServerService.java b/app/src/main/java/com/javispedro/vndroid/ServerService.java
index bf72d21..96420df 100644
--- a/app/src/main/java/com/javispedro/vndroid/ServerService.java
+++ b/app/src/main/java/com/javispedro/vndroid/ServerService.java
@@ -1,61 +1,80 @@
 package com.javispedro.vndroid;
 
-import android.app.Activity;
 import android.app.Notification;
 import android.app.Service;
 import android.content.Intent;
 import android.content.res.Configuration;
 import android.media.Image;
-import android.media.projection.MediaProjection;
-import android.media.projection.MediaProjectionManager;
+import android.os.Binder;
 import android.os.IBinder;
 import android.util.Log;
-import android.view.WindowManager;
 import android.widget.Toast;
 
 import com.javispedro.vndroid.keymaps.AndroidKeyHandler;
 import com.javispedro.vndroid.keymaps.SpanishKeyHandler;
 
+import java.lang.ref.WeakReference;
+import java.net.InetAddress;
+import java.net.NetworkInterface;
+import java.util.Enumeration;
+import java.util.LinkedList;
+import java.util.List;
+
 public class ServerService extends Service {
     private static final String TAG = ServerService.class.getSimpleName();
-    public static final String ACTION_START = "ACTION_START";
-    public static final String ACTION_STOP = "ACTION_STOP";
-    public static final String ACTION_NOTIFY_MEDIA_PROJECTION_RESULT = "ACTION_NOTIFY_MEDIA_PROJECTION_RESULT";
+
+    public static final String ACTION_START_SERVER = "ACTION_START_SERVER";
+    public static final String ACTION_STOP_SERVER = "ACTION_STOP_SERVER";
+
+    public class ServerBinder extends Binder {
+        ServerService getService() {
+            return ServerService.this;
+        }
+    }
+    public interface ServerStatusCallback {
+        void onServerStatusChanged();
+        void onNumClientChanged();
+    }
+
+    private ServerBinder binder;
+    private WeakReference<ServerStatusCallback> callback;
 
     private ScreenGrabber screenGrabber;
     private RFBServer rfbServer;
     private PointerEventOutput pointerOut;
     private KeyEventOutput keyOut;
 
-    public ServerService() {
-    }
-
     @Override
     public void onCreate() {
+        Log.d(TAG, "onCreate");
+        binder = new ServerBinder();
         ServerRunningNotification.initNotificationChannel(this);
         System.loadLibrary("native-lib");
     }
 
     @Override
+    public void onDestroy() {
+        Log.d(TAG, "onDestroy");
+        cleanupServer();
+        binder = null;
+        callback = null;
+    }
+
+    @Override
     public IBinder onBind(Intent intent) {
-        throw new UnsupportedOperationException("Not implemented");
+        return binder;
     }
 
     @Override
     public int onStartCommand(Intent intent, int flags, int startId) {
-        if (intent != null) {
-            switch (intent.getAction()) {
-                case ACTION_START:
-                    start();
-                    break;
-                case ACTION_STOP:
-                    stop();
-                    break;
-                case ACTION_NOTIFY_MEDIA_PROJECTION_RESULT:
-                    notifyMediaProjectionResult(intent.getIntExtra("resultCode", Activity.RESULT_CANCELED),
-                            (Intent) intent.getParcelableExtra("resultData"));
-                    break;
-            }
+        Log.d(TAG, "onStartCommand intent=" + intent);
+        switch (intent.getAction()) {
+            case ACTION_START_SERVER:
+                startServer();
+                return START_REDELIVER_INTENT;
+            case ACTION_STOP_SERVER:
+                stopServer();
+                return START_NOT_STICKY;
         }
         return super.onStartCommand(intent, flags, startId);
     }
@@ -69,43 +88,15 @@ public class ServerService extends Service {
         }
     }
 
-    protected class ScreenGrabberCallback implements ScreenGrabber.Callback {
-        @Override
-        public void onImage(Image image) {
-            if (rfbServer != null) {
-                rfbServer.putImage(image);
-            } else {
-                image.close();
-            }
+    public void setServerStatusCallback(ServerStatusCallback callback) {
+        if (callback != null) {
+            this.callback = new WeakReference<>(callback);
+        } else {
+            this.callback = null;
         }
     }
 
-    protected class EventCallback implements RFBServer.EventCallback {
-        @Override
-        public void onPointerEvent(int buttonMask, int x, int y) {
-            try {
-                x = screenGrabber.scaleInputX(x);
-                y = screenGrabber.scaleInputY(y);
-                pointerOut.postPointerEvent((byte) buttonMask, x, y);
-            } catch (Exception e) {
-                Log.e(TAG, "Exception on pointer EventCallback: " + e.toString());
-                e.printStackTrace();
-                // Need to supress the exception, otherwise we'll crash JNI
-            }
-        }
-
-        @Override
-        public void onKeyEvent(int key, boolean state) {
-            try {
-                keyOut.postKeyEvent(key, state);
-            } catch (Exception e) {
-                Log.e(TAG, "Exception on key EventCallback: " + e.toString());
-                e.printStackTrace();
-            }
-        }
-    }
-
-    protected void start() {
+    public void startServer() {
         if (rfbServer != null) {
             Log.w(TAG, "cannot start, already started");
             return;
@@ -113,6 +104,9 @@ public class ServerService extends Service {
 
         Log.d(TAG, "starting");
 
+        Notification notification = ServerRunningNotification.build(this);
+        startForeground(1, notification);
+
         if (!ControlService.isServiceStarted()) {
             Toast toast = Toast.makeText(this, R.string.toast_no_input_service, Toast.LENGTH_SHORT);
             toast.show();
@@ -123,7 +117,6 @@ public class ServerService extends Service {
         keyOut.addHandler(new AndroidKeyHandler());
         keyOut.addHandler(new SpanishKeyHandler());
 
-
         if (screenGrabber == null) {
             screenGrabber = new ScreenVirtualGrabber(this);
         }
@@ -135,13 +128,61 @@ public class ServerService extends Service {
         screenGrabber.setCallback(new ScreenGrabberCallback());
         screenGrabber.start();
 
-        Notification notification = ServerRunningNotification.build(this);
-        startForeground(1, notification);
+        notifyServerStatusChanged();
     }
 
-    protected void stop() {
+    public void stopServer() {
         Log.d(TAG, "stopping");
 
+        cleanupServer();
+
+        stopForeground(true);
+        stopSelf();
+
+        notifyServerStatusChanged();
+    }
+
+    public boolean isServerActive() {
+        return rfbServer != null;
+    }
+
+    public void setMediaProjectionResult(int resultCode, Intent data) {
+        if (screenGrabber != null) {
+            Log.w(TAG, "already have an screen grabber");
+        }
+
+        screenGrabber = new ScreenMirrorGrabber(this, resultCode, data);
+    }
+
+    public int getListeningDisplay() {
+        return 0;
+    }
+
+    public List<String> getListeningIPAddresses() {
+        LinkedList<String> result = new LinkedList<String>();
+        try {
+            for (Enumeration<NetworkInterface> netif_it = NetworkInterface.getNetworkInterfaces(); netif_it.hasMoreElements(); ) {
+                NetworkInterface netif = netif_it.nextElement();
+
+                for (Enumeration<InetAddress> addr_it = netif.getInetAddresses(); addr_it.hasMoreElements(); ) {
+                    InetAddress addr = addr_it.nextElement();
+
+                    if (addr.isLoopbackAddress()) continue;
+
+                    result.add(addr.getHostAddress());
+                }
+            }
+        } catch (Exception ex) {
+            Log.w(TAG, "While enumerating IP addresses: " + ex.toString());
+        }
+        return result;
+    }
+
+    public int getNumClients() {
+        return rfbServer.getNumClients();
+    }
+
+    private void cleanupServer() {
         if (rfbServer != null) {
             rfbServer.stop();
             rfbServer = null;
@@ -156,20 +197,67 @@ public class ServerService extends Service {
         if (keyOut != null) {
             keyOut = null;
         }
+    }
 
-        stopForeground(true);
-        stopSelf();
+    private ServerStatusCallback getStatusCallback() {
+        return callback == null ? null : callback.get();
     }
 
-    protected void notifyMediaProjectionResult(int resultCode, Intent data) {
-        if (screenGrabber != null) {
-            Log.w(TAG, "already have an screen grabber");
+    private void notifyServerStatusChanged() {
+        ServerStatusCallback cb = getStatusCallback();
+        if (cb == null) return;
+        cb.onServerStatusChanged();
+    }
+
+    private void notifyNumClientChanged() {
+        ServerStatusCallback cb = getStatusCallback();
+        if (cb == null) return;
+        cb.onNumClientChanged();
+    }
+
+    private class ScreenGrabberCallback implements ScreenGrabber.Callback {
+        @Override
+        public void onImage(Image image) {
+            if (rfbServer != null) {
+                rfbServer.putImage(image);
+            } else {
+                image.close();
+            }
         }
-        MediaProjectionManager manager = getSystemService(MediaProjectionManager.class);
-        MediaProjection projection = manager.getMediaProjection(resultCode, data);
+    }
 
-        WindowManager wm = getSystemService(WindowManager.class);
+    private class EventCallback implements RFBServer.EventCallback {
+        @Override
+        public void onPointerEvent(int buttonMask, int x, int y) {
+            try {
+                x = screenGrabber.scaleInputX(x);
+                y = screenGrabber.scaleInputY(y);
+                pointerOut.postPointerEvent((byte) buttonMask, x, y);
+            } catch (Exception e) {
+                Log.e(TAG, "Exception on pointer EventCallback: " + e.toString());
+                e.printStackTrace();
+                // Need to suppress the exception, otherwise we'll crash JNI
+            }
+        }
 
-        screenGrabber = new ScreenMirrorGrabber(this, projection, wm.getDefaultDisplay());
+        @Override
+        public void onKeyEvent(int key, boolean state) {
+            try {
+                keyOut.postKeyEvent(key, state);
+            } catch (Exception e) {
+                Log.e(TAG, "Exception on key EventCallback: " + e.toString());
+                e.printStackTrace();
+            }
+        }
+
+        @Override
+        public void onClientEvent() {
+            try {
+                notifyNumClientChanged();
+            } catch (Exception e) {
+                Log.e(TAG, "Exception on client EventCallback: " + e.toString());
+                e.printStackTrace();
+            }
+        }
     }
 }
diff --git a/app/src/main/java/com/javispedro/vndroid/SettingsActivity.java b/app/src/main/java/com/javispedro/vndroid/SettingsActivity.java
new file mode 100644
index 0000000..676af3d
--- /dev/null
+++ b/app/src/main/java/com/javispedro/vndroid/SettingsActivity.java
@@ -0,0 +1,213 @@
+package com.javispedro.vndroid;
+
+import android.app.Activity;
+import android.content.ComponentName;
+import android.content.Context;
+import android.content.Intent;
+import android.content.ServiceConnection;
+import android.media.projection.MediaProjectionManager;
+import android.os.Bundle;
+import android.os.IBinder;
+import android.util.Log;
+import android.widget.Toast;
+
+import androidx.annotation.Nullable;
+import androidx.appcompat.app.AppCompatActivity;
+import androidx.preference.Preference;
+import androidx.preference.PreferenceFragmentCompat;
+import androidx.preference.TwoStatePreference;
+
+import java.util.List;
+
+public class SettingsActivity extends AppCompatActivity {
+    private static final String TAG = SettingsActivity.class.getSimpleName();
+
+    private static final int REQUEST_MEDIA_PROJECTION = 1;
+
+    private static final boolean mirrorScreenMode = true;
+
+
+    public static class SettingsFragment extends PreferenceFragmentCompat implements ServerService.ServerStatusCallback {
+        private ServerConnection serverConnection = null;
+
+        @Override
+        public void onCreate(@Nullable Bundle savedInstanceState) {
+            super.onCreate(savedInstanceState);
+        }
+
+        @Override
+        public void onCreatePreferences(Bundle savedInstanceState, String rootKey) {
+            setPreferencesFromResource(R.xml.root_preferences, rootKey);
+            findPreference(getString(R.string.settings_enable_key)).setOnPreferenceClickListener(new Preference.OnPreferenceClickListener() {
+                @Override
+                public boolean onPreferenceClick(Preference preference) {
+                    TwoStatePreference pref = (TwoStatePreference) preference;
+                    setServerEnabled(pref.isChecked());
+                    return true;
+                }
+            });
+        }
+
+        @Override
+        public void onStart() {
+            super.onStart();
+            serverConnection = new ServerConnection();
+            serverConnection.bind(requireActivity(), this);
+        }
+
+        @Override
+        public void onStop() {
+            serverConnection.close(requireActivity());
+            serverConnection = null;
+            super.onStop();
+        }
+
+        @Override
+        public void onActivityResult(int requestCode, int resultCode, Intent data) {
+            switch (requestCode) {
+                case REQUEST_MEDIA_PROJECTION:
+                    notifyMediaProjectionResult(resultCode, data);
+                    return;
+            }
+            super.onActivityResult(requestCode, resultCode, data);
+        }
+
+        @Override
+        public void onServerStatusChanged() {
+            postUpdateServerStatus();
+        }
+
+        @Override
+        public void onNumClientChanged() {
+            postUpdateServerStatus();
+        }
+
+        private void setServerEnabled(boolean state) {
+            Log.d(TAG, "setServerEnabled: " + state);
+            ServerService server = serverConnection.getServer();
+            if (state) {
+                if (server == null) {
+                    throw new IllegalStateException("ServerService not bound");
+                }
+                if (server.isServerActive()) return;
+
+                if (mirrorScreenMode) {
+                    MediaProjectionManager manager = requireContext().getSystemService(MediaProjectionManager.class);
+                    startActivityForResult(manager.createScreenCaptureIntent(), REQUEST_MEDIA_PROJECTION);
+                } else {
+                    server.startServer();
+                }
+            } else {
+                if (server == null) return;
+                server.stopServer();
+            }
+        }
+
+        private void notifyMediaProjectionResult(int resultCode, Intent resultData) {
+            if (resultCode != Activity.RESULT_OK) {
+                Log.w(TAG, "User cancelled media projection");
+                Toast.makeText(requireContext(), getString(R.string.toast_no_mirror_permission), Toast.LENGTH_SHORT).show();
+                updateServerStatus();
+                return;
+            }
+
+            ServerService server = serverConnection.getServer();
+            if (server == null) {
+                Log.e(TAG, "server died before projection could be sent");
+                updateServerStatus();
+                return;
+            }
+            if (server.isServerActive()) {
+                Log.w(TAG, "server already active");
+                updateServerStatus();
+                return;
+            }
+
+            server.setMediaProjectionResult(resultCode, resultData);
+            server.startServer();
+        }
+
+        private void updateServerStatus() {
+            TwoStatePreference enablePref = findPreference(getString(R.string.settings_enable_key));
+            Preference statusPref = findPreference(getString(R.string.settings_status_key));
+            ServerService server = serverConnection.getServer();
+            if (server != null && server.isServerActive()) {
+                enablePref.setChecked(true);
+                StringBuilder sb = new StringBuilder();
+                int display = server.getListeningDisplay();
+                List<String> ips = server.getListeningIPAddresses();
+                if (!ips.isEmpty()) {
+                    sb.append('\n');
+                    sb.append(getString(R.string.status_server_addresses));
+                    for (String ip : ips) {
+                        sb.append(' ');
+                        sb.append(ip);
+                        sb.append(':');
+                        sb.append(display);
+                    }
+                }
+                int numClients = server.getNumClients();
+                if (numClients > 0) {
+                    sb.append('\n');
+                    sb.append(getResources().getQuantityString(R.plurals.status_num_clients, numClients, numClients));
+                }
+                statusPref.setSummary(sb.toString());
+            } else {
+                enablePref.setChecked(false);
+                statusPref.setSummary("");
+            }
+        }
+
+        private void postUpdateServerStatus() {
+            requireActivity().runOnUiThread(new Runnable() {
+                public void run() {
+                    updateServerStatus();
+                }
+            });
+        }
+    }
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.settings_activity);
+        getSupportFragmentManager()
+                .beginTransaction()
+                .replace(R.id.settings, new SettingsFragment())
+                .commit();
+    }
+
+    private static class ServerConnection implements ServiceConnection {
+        private ServerService server = null;
+        private ServerService.ServerStatusCallback callback = null;
+
+        public void bind(Activity activity, ServerService.ServerStatusCallback callback) {
+            this.callback = callback;
+            activity.bindService(new Intent(activity, ServerService.class), this, Context.BIND_AUTO_CREATE);
+        }
+
+        public void close(Activity activity) {
+            server.setServerStatusCallback(null);
+            activity.unbindService(this);
+        }
+
+        public boolean connected() {
+            return server != null;
+        }
+
+        public @Nullable ServerService getServer() {
+            return server;
+        }
+
+        @Override
+        public void onServiceConnected(ComponentName name, IBinder service) {
+            server = ((ServerService.ServerBinder) service).getService();
+            server.setServerStatusCallback(this.callback);
+        }
+
+        @Override
+        public void onServiceDisconnected(ComponentName name) {
+            server = null;
+        }
+    }
+}
\ No newline at end of file
diff --git a/app/src/main/java/com/javispedro/vndroid/SetupActivity.java b/app/src/main/java/com/javispedro/vndroid/SetupActivity.java
deleted file mode 100644
index 123bbe7..0000000
--- a/app/src/main/java/com/javispedro/vndroid/SetupActivity.java
+++ /dev/null
@@ -1,78 +0,0 @@
-package com.javispedro.vndroid;
-
-import android.app.Activity;
-import android.content.Intent;
-import android.media.projection.MediaProjectionManager;
-import android.os.Bundle;
-import android.support.v7.app.AppCompatActivity;
-import android.util.Log;
-import android.view.View;
-
-public class SetupActivity extends AppCompatActivity {
-    private static String TAG = SetupActivity.class.getSimpleName();
-
-    private static final int REQUEST_MEDIA_PROJECTION = 1;
-
-    private boolean mirror = true;
-
-    @Override
-    protected void onCreate(Bundle savedInstanceState) {
-        super.onCreate(savedInstanceState);
-        setContentView(R.layout.activity_setup);
-    }
-
-    @Override
-    public void onActivityResult(int requestCode, int resultCode, Intent data)
-    {
-        switch (requestCode) {
-            case REQUEST_MEDIA_PROJECTION:
-                if (resultCode != Activity.RESULT_OK) {
-                    Log.w(TAG, "User cancelled media projection");
-                    return;
-                }
-
-                notifyMediaProjectionResult(resultCode, data);
-                startServer();
-
-                break;
-        }
-    }
-
-    private void startServer()
-    {
-        Intent intent = new Intent(this, ServerService.class);
-        intent.setAction(ServerService.ACTION_START);
-        startService(intent);
-    }
-
-    private void stopServer()
-    {
-        Intent intent = new Intent(this, ServerService.class);
-        intent.setAction(ServerService.ACTION_STOP);
-        startService(intent);
-    }
-
-    private void notifyMediaProjectionResult(int resultCode, Intent resultData)
-    {
-        Intent intent = new Intent(this, ServerService.class);
-        intent.setAction(ServerService.ACTION_NOTIFY_MEDIA_PROJECTION_RESULT);
-        intent.putExtra("resultCode", resultCode);
-        intent.putExtra("resultData", resultData);
-        startService(intent);
-    }
-
-    public void onStartClick(View view) {
-        Log.d(TAG, "onStartClick");
-        if (mirror) {
-            MediaProjectionManager manager = getSystemService(MediaProjectionManager.class);
-            startActivityForResult(manager.createScreenCaptureIntent(), REQUEST_MEDIA_PROJECTION);
-        } else {
-            startServer();
-        }
-    }
-
-    public void onStopClick(View view) {
-        Log.d(TAG, "onStopClick");
-        stopServer();
-    }
-}
diff --git a/app/src/main/res/layout/activity_setup.xml b/app/src/main/res/layout/activity_setup.xml
deleted file mode 100644
index 9512149..0000000
--- a/app/src/main/res/layout/activity_setup.xml
+++ /dev/null
@@ -1,45 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
-    xmlns:app="http://schemas.android.com/apk/res-auto"
-    xmlns:tools="http://schemas.android.com/tools"
-    android:layout_width="match_parent"
-    android:layout_height="match_parent"
-    tools:context=".SetupActivity">
-
-    <LinearLayout
-        android:layout_width="wrap_content"
-        android:layout_height="wrap_content"
-        android:layout_marginStart="8dp"
-        android:layout_marginTop="8dp"
-        android:layout_marginEnd="8dp"
-        android:layout_marginBottom="8dp"
-        android:gravity="center"
-        android:orientation="horizontal"
-        app:layout_constraintBottom_toBottomOf="parent"
-        app:layout_constraintEnd_toEndOf="parent"
-        app:layout_constraintStart_toStartOf="parent"
-        app:layout_constraintTop_toTopOf="parent"
-        app:layout_constraintVertical_bias="0.19">
-
-        <Button
-            android:id="@+id/btnStart"
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:onClick="onStartClick"
-            android:text="@string/action_start" />
-
-        <Space
-            android:layout_width="75dp"
-            android:layout_height="wrap_content"
-            android:layout_weight="1" />
-
-        <Button
-            android:id="@+id/btnStop"
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
-            android:onClick="onStopClick"
-            android:text="@string/action_stop" />
-
-    </LinearLayout>
-
-</android.support.constraint.ConstraintLayout>
\ No newline at end of file
diff --git a/app/src/main/res/layout/settings_activity.xml b/app/src/main/res/layout/settings_activity.xml
new file mode 100644
index 0000000..de6591a
--- /dev/null
+++ b/app/src/main/res/layout/settings_activity.xml
@@ -0,0 +1,9 @@
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent">
+
+    <FrameLayout
+        android:id="@+id/settings"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent" />
+</LinearLayout>
\ No newline at end of file
diff --git a/app/src/main/res/values/arrays.xml b/app/src/main/res/values/arrays.xml
new file mode 100644
index 0000000..6b30d8d
--- /dev/null
+++ b/app/src/main/res/values/arrays.xml
@@ -0,0 +1,3 @@
+<resources>
+
+</resources>
\ No newline at end of file
diff --git a/app/src/main/res/values/colors.xml b/app/src/main/res/values/colors.xml
index 69b2233..d044e23 100644
--- a/app/src/main/res/values/colors.xml
+++ b/app/src/main/res/values/colors.xml
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <resources>
-    <color name="colorPrimary">#008577</color>
-    <color name="colorPrimaryDark">#00574B</color>
-    <color name="colorAccent">#D81B60</color>
+    <color name="colorPrimary">#2196F3</color>
+    <color name="colorPrimaryDark">#3F51B5</color>
+    <color name="colorAccent">#00BCD4</color>
 </resources>
diff --git a/app/src/main/res/values/dimens.xml b/app/src/main/res/values/dimens.xml
new file mode 100644
index 0000000..8542005
--- /dev/null
+++ b/app/src/main/res/values/dimens.xml
@@ -0,0 +1,2 @@
+<resources>
+</resources>
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 9c0ca47..bf12595 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -7,5 +7,18 @@
     <string name="action_start">Start</string>
     <string name="action_stop">Stop</string>
 
+    <string name="toast_no_mirror_permission">Cannot continue without broadcast screen permission</string>
     <string name="toast_no_input_service">Accessibility service not enabled: clients will not be able to control</string>
+
+    <!-- Settings activity -->
+    <string name="settings_category_main">Main</string>
+    <string name="settings_enable_key" translatable="false">enable</string>
+    <string name="settings_enable_title">Enable server</string>
+    <string name="settings_status_key" translatable="false">status</string>
+    <string name="status_server_enabled">Server enabled</string>
+    <string name="status_server_addresses">Server addresses:</string>
+    <plurals name="status_num_clients">
+        <item quantity="one">%d client connected.</item>
+        <item quantity="other">%d clients connected.</item>
+    </plurals>
 </resources>
diff --git a/app/src/main/res/values/styles.xml b/app/src/main/res/values/styles.xml
index 5885930..545b9c6 100644
--- a/app/src/main/res/values/styles.xml
+++ b/app/src/main/res/values/styles.xml
@@ -8,4 +8,13 @@
         <item name="colorAccent">@color/colorAccent</item>
     </style>
 
+    <style name="AppTheme.NoActionBar">
+        <item name="windowActionBar">false</item>
+        <item name="windowNoTitle">true</item>
+    </style>
+
+    <style name="AppTheme.AppBarOverlay" parent="ThemeOverlay.AppCompat.Dark.ActionBar" />
+
+    <style name="AppTheme.PopupOverlay" parent="ThemeOverlay.AppCompat.Light" />
+
 </resources>
diff --git a/app/src/main/res/xml/root_preferences.xml b/app/src/main/res/xml/root_preferences.xml
new file mode 100644
index 0000000..daedcc8
--- /dev/null
+++ b/app/src/main/res/xml/root_preferences.xml
@@ -0,0 +1,31 @@
+<!--
+  ~ Copyright 2018 The app Open Source Project
+  ~
+  ~ Licensed under the Apache License, Version 2.0 (the "License");
+  ~ you may not use this file except in compliance with the License.
+  ~ You may obtain a copy of the License at
+  ~
+  ~      http://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing, software
+  ~ distributed under the License is distributed on an "AS IS" BASIS,
+  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  ~ See the License for the specific language governing permissions and
+  ~ limitations under the License.
+  -->
+
+<PreferenceScreen xmlns:app="http://schemas.android.com/apk/res-auto">
+
+    <PreferenceCategory app:title="@string/settings_category_main">
+        <SwitchPreferenceCompat
+            app:key="@string/settings_enable_key"
+            app:title="@string/settings_enable_title"
+            app:persistent="false" />
+
+        <Preference
+            app:key="status"
+            app:title=""
+            app:persistent="false"/>
+    </PreferenceCategory>
+
+</PreferenceScreen>
diff --git a/gradle.properties b/gradle.properties
index 82618ce..f6853fb 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -11,5 +11,9 @@ org.gradle.jvmargs=-Xmx1536m
 # This option should only be used with decoupled projects. More details, visit
 # http://www.gradle.org/docs/current/userguide/multi_project_builds.html#sec:decoupled_projects
 # org.gradle.parallel=true
-
-
+# AndroidX package structure to make it clearer which packages are bundled with the
+# Android operating system, and which are packaged with your app's APK
+# https://developer.android.com/topic/libraries/support-library/androidx-rn
+android.useAndroidX=true
+# Automatically convert third-party libraries to use AndroidX
+android.enableJetifier=true
\ No newline at end of file