android: clearing the activity from view concerns

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

 package com.reactnativenavigation.controllers;
 
 import android.os.Bundle;
+import android.support.annotation.Nullable;
 import android.support.v7.app.AppCompatActivity;
 import android.view.View;
 
 import com.facebook.react.modules.core.DefaultHardwareBackBtnHandler;
 import com.facebook.react.shell.MainReactPackage;
 import com.reactnativenavigation.R;
-import com.reactnativenavigation.layout.StackLayout;
 import com.reactnativenavigation.react.NavigationEventEmitter;
 import com.reactnativenavigation.react.NavigationPackage;
 import com.reactnativenavigation.react.ReactDevPermission;
 public class NavigationActivity extends AppCompatActivity implements DefaultHardwareBackBtnHandler {
     public static NavigationActivity instance;
     private ReactNativeHost host;
-    private StackLayout root;
+    private View contentView;
 
     @Override
     public void onCreate(Bundle savedInstanceState) {
         });
     }
 
+    @Override
+    public void setContentView(View contentView) {
+        super.setContentView(contentView);
+        this.contentView = contentView;
+    }
+
+    @Nullable
+    public View getContentView() {
+        return contentView;
+    }
+
     @Override
     protected void onResume() {
         super.onResume();
     public ReactNativeHost getHost() {
         return host;
     }
-
-    public void setRoot(StackLayout rootView) {
-        this.root = rootView;
-        setContentView(rootView.asView());
-    }
-
-    public void push(View view) {
-        root.push(view);
-    }
-
-    public void pop() {
-        root.pop();
-    }
 }

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

 
                 final LayoutNode layoutTreeRoot = readableMapToLayoutNode(layoutTree);
                 final View rootView = factory.create(layoutTreeRoot);
-                NavigationActivity.instance.setRoot((StackLayout) rootView);
+                NavigationActivity.instance.setContentView(rootView);
             }
         });
     }
                         }, new BottomTabsCreator());
                 final LayoutNode layoutNode = readableMapToLayoutNode(layout);
                 final View rootView = factory.create(layoutNode);
-                NavigationActivity.instance.push(rootView);
+                ((StackLayout) NavigationActivity.instance.getContentView()).push(rootView);
             }
         });
     }
         NavigationActivity.instance.runOnUiThread(new Runnable() {
             @Override
             public void run() {
-                NavigationActivity.instance.pop();
+                ((StackLayout) NavigationActivity.instance.getContentView()).pop();
             }
         });
     }