react-native-navigation/lib/android/app/src/main/java/com/reactnativenavigation/NavigationActivity.java

package com.reactnativenavigation;

import android.annotation.TargetApi;
import android.support.annotation.NonNull;

import android.content.Intent;
import android.os.Bundle;
import android.os.Build;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.view.KeyEvent;
import android.view.View;

import com.facebook.react.modules.core.DefaultHardwareBackBtnHandler;
import com.reactnativenavigation.presentation.OverlayManager;
import com.reactnativenavigation.react.ReactGateway;
import com.reactnativenavigation.utils.CommandListenerAdapter;
import com.reactnativenavigation.viewcontrollers.ChildControllersRegistry;
import com.reactnativenavigation.viewcontrollers.Navigator;

import com.facebook.react.modules.core.PermissionAwareActivity;
import com.facebook.react.modules.core.PermissionListener;

public class NavigationActivity extends AppCompatActivity implements DefaultHardwareBackBtnHandler, PermissionAwareActivity {
    @Nullable
    private PermissionListener mPermissionListener;
    
    protected Navigator navigator;

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        navigator = new Navigator(this, new ChildControllersRegistry(), new OverlayManager());
        getReactGateway().onActivityCreated(this);
        getReactGateway().addReloadListener(navigator);
        navigator.getView().setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN);
        setContentView(navigator.getView());
    }

    @Override
    protected void onResume() {
        super.onResume();
        getReactGateway().onActivityResumed(this);
    }

    @Override
    protected void onPause() {
        super.onPause();
        getReactGateway().onActivityPaused(this);
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        navigator.destroy();
        getReactGateway().removeReloadListener(navigator);
        getReactGateway().onActivityDestroyed(this);
    }

    @Override
    public void invokeDefaultOnBackPressed() {
        if (!navigator.handleBack(new CommandListenerAdapter())) {
            super.onBackPressed();
        }
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        getReactGateway().onActivityResult(this, requestCode, resultCode, data);
    }

    @Override
    public void onBackPressed() {
        getReactGateway().onBackPressed();
    }

    @Override
    public boolean onKeyUp(final int keyCode, final KeyEvent event) {
        return getReactGateway().onKeyUp(keyCode) || super.onKeyUp(keyCode, event);
    }

    public ReactGateway getReactGateway() {
        return app().getReactGateway();
    }

    private NavigationApplication app() {
        return (NavigationApplication) getApplication();
    }

    public Navigator getNavigator() {
        return navigator;
    }

    @TargetApi(Build.VERSION_CODES.M)
    public void requestPermissions(String[] permissions, int requestCode, PermissionListener listener) {
        mPermissionListener = listener;
        requestPermissions(permissions, requestCode);
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        NavigationApplication.instance.onRequestPermissionsResult(requestCode, permissions, grantResults);
        if (mPermissionListener != null && mPermissionListener.onRequestPermissionsResult(requestCode, permissions, grantResults)) {
            mPermissionListener = null;
        }
    }
}