It shows welcome screen

android/app/src/main/AndroidManifest.xml

     package="com.reactnativenavigation">
 
     <application>
-        <!--<activity android:name=".controllers.NavigationActivity" />-->
+        <activity android:name=".controllers.NavigationActivity"/>
         <!--<activity-->
             <!--android:name=".controllers.PortraitNavigationActivity"-->
             <!--android:screenOrientation="portrait" />-->

android/app/src/main/java/com/reactnativenavigation/container/Container.java

+package com.reactnativenavigation.container;
+
+public class Container {
+
+}

android/app/src/main/java/com/reactnativenavigation/controllers/NavigationActivity.java

 import com.facebook.react.ReactInstanceManager;
 import com.facebook.react.ReactNativeHost;
 import com.facebook.react.ReactPackage;
+import com.facebook.react.ReactRootView;
 import com.facebook.react.bridge.ReactContext;
 import com.facebook.react.modules.core.DefaultHardwareBackBtnHandler;
 import com.facebook.react.shell.MainReactPackage;
 import java.util.List;
 
 public class NavigationActivity extends AppCompatActivity implements DefaultHardwareBackBtnHandler {
-
+    public static NavigationActivity instance;
     private ReactNativeHost host;
 
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
+        instance = this;
         setContentView(R.layout.splash);
         host = new ReactNativeHost(getApplication()) {
             @Override
             }
         });
         host.getReactInstanceManager().createReactContextInBackground();
-
-
     }
 
     @Override
         host.getReactInstanceManager().onHostResume(this, this);
     }
 
+    @Override
+    protected void onPause() {
+        super.onPause();
+        host.getReactInstanceManager().onHostPause(this);
+    }
+
+    @Override
+    protected void onDestroy() {
+        super.onDestroy();
+        instance = null;
+        host.getReactInstanceManager().onHostDestroy(this);
+    }
+
     @Override
     public void invokeDefaultOnBackPressed() {
         onBackPressed();
     }
+
+    public void setRoot(String name, Bundle args) {
+        ReactRootView v = new ReactRootView(getApplicationContext());
+        setContentView(v);
+        v.startReactApplication(host.getReactInstanceManager(), name, args);
+    }
 }

android/app/src/main/java/com/reactnativenavigation/layout/Layout.java

+package com.reactnativenavigation.layout;
+
+import android.content.Context;
+import android.graphics.Color;
+import android.widget.FrameLayout;
+
+public class Layout extends FrameLayout {
+    public Layout(Context context) {
+        super(context);
+        setBackgroundColor(Color.RED);
+    }
+}

android/app/src/main/java/com/reactnativenavigation/react/NavigationModule.java

 package com.reactnativenavigation.react;
 
+import android.os.Bundle;
+
 import com.facebook.react.bridge.ReactApplicationContext;
 import com.facebook.react.bridge.ReactContextBaseJavaModule;
 import com.facebook.react.bridge.ReactMethod;
 import com.facebook.react.bridge.ReadableMap;
+import com.reactnativenavigation.controllers.NavigationActivity;
 
 public class NavigationModule extends ReactContextBaseJavaModule {
     public static final String NAME = "RNNBridgeModule";
     }
 
     @ReactMethod
-    public void setRoot(ReadableMap layoutTree) {
-        
+    public void setRoot(final ReadableMap layoutTree) {
+        NavigationActivity.instance.runOnUiThread(new Runnable() {
+            @Override
+            public void run() {
+                Bundle args = new Bundle();
+                args.putString("id", layoutTree.getArray("children").getMap(0).getString("id"));
+                NavigationActivity.instance.setRoot(layoutTree.getArray("children").getMap(0).getMap("data").getString("name"), args);
+            }
+        });
     }
 }

android/app/src/main/res/layout/new_root.xml

+<?xml version="1.0" encoding="utf-8"?>
+<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
+              android:layout_width="match_parent"
+              android:layout_height="match_parent"
+              android:orientation="vertical">
+    <TextView
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_centerInParent="true"
+        android:text="new root :)"/>
+</RelativeLayout>

src/adapters/NativeCommandsSender.js

   }
 
   setRoot(layoutTree) {
+    console.log(layoutTree);
     this.nativeCommandsModule.setRoot(layoutTree);
     return Promise.resolve(layoutTree);
   }

src/commands/AppCommands.js

   }
 
   setRoot(simpleApi) {
+    console.log('AppCommands', 'setRoot');
     const input = _.cloneDeep(simpleApi);
     const layout = this.layoutTreeParser.parseFromSimpleJSON(input);
     this.layoutTreeCrawler.crawl(layout);
+    console.log('layout: ', JSON.stringify(layout));
     return this.nativeCommandsSender.setRoot(layout);
   }
 }