Convert to using new React Native MainActivity template

Adjusted the README to reflect the modern way of doing things.

README.md

@@ -25,7 +25,7 @@ The ReactNative example project is in the `examples/ReactExample` directory. You
 - Run this command from the project directory: `react-native link realm`
 - Open `MainActivity.java` inside your project:
   - Add `import io.realm.react.RealmReactPackage;` under the other imports.
-  - Add `.addPackage(new RealmReactPackage())` directly under `.addPackage(new MainReactPackage())`
+  - Add `new RealmReactPackage()` to the list returned by the `getPackages()` method.
 - You can now `require('realm')` in your Android app's JS to use Realm!
 
 ## Getting Started

examples/ReactExample/android/app/src/main/java/io/realm/react/example/MainActivity.java

@@ -1,81 +1,43 @@
 package io.realm.react.example;
 
-import android.app.Activity;
+import com.facebook.react.ReactActivity;
-import android.os.Bundle;
+import com.facebook.react.ReactPackage;
-import android.view.KeyEvent;
-
-import com.facebook.react.LifecycleState;
-import com.facebook.react.ReactInstanceManager;
-import com.facebook.react.ReactRootView;
-import com.facebook.react.bridge.ReactApplicationContext;
-import com.facebook.react.modules.core.DefaultHardwareBackBtnHandler;
 import com.facebook.react.shell.MainReactPackage;
 
+import java.util.Arrays;
+import java.util.List;
+
 import io.realm.react.RealmReactPackage;
 
-public class MainActivity extends Activity implements DefaultHardwareBackBtnHandler {
+public class MainActivity extends ReactActivity {
-
-    private ReactInstanceManager mReactInstanceManager;
-    private ReactRootView mReactRootView;
 
+    /**
+     * Returns the name of the main component registered from JavaScript.
+     * This is used to schedule rendering of the component.
+     */
     @Override
-    protected void onCreate(Bundle savedInstanceState) {
+    protected String getMainComponentName() {
-        super.onCreate(savedInstanceState);
+        return "ReactExample";
-        mReactRootView = new ReactRootView(this);
-
-        mReactInstanceManager = ReactInstanceManager.builder()
-                .setApplication(getApplication())
-                .setBundleAssetName("index.android.bundle")
-                .setJSMainModuleName("index.android")
-                .addPackage(new MainReactPackage())
-                .addPackage(new RealmReactPackage())
-                .setUseDeveloperSupport(BuildConfig.DEBUG)
-                .setInitialLifecycleState(LifecycleState.RESUMED)
-                .build();
-
-        mReactRootView.startReactApplication(mReactInstanceManager, "ReactExample", null);
-
-        setContentView(mReactRootView);
     }
 
+    /**
+     * Returns whether dev mode should be enabled.
+     * This enables e.g. the dev menu.
+     */
     @Override
-    public boolean onKeyUp(int keyCode, KeyEvent event) {
+    protected boolean getUseDeveloperSupport() {
-        if (keyCode == KeyEvent.KEYCODE_MENU && mReactInstanceManager != null) {
+        return BuildConfig.DEBUG;
-            mReactInstanceManager.showDevOptionsDialog();
-            return true;
-        }
-        return super.onKeyUp(keyCode, event);
     }
 
+    /**
+     * A list of packages used by the app. If the app uses additional views
+     * or modules besides the default ones, add more packages here.
+     */
     @Override
-    public void onBackPressed() {
+    protected List<ReactPackage> getPackages() {
-      if (mReactInstanceManager != null) {
+        return Arrays.<ReactPackage>asList(
-        mReactInstanceManager.onBackPressed();
+            new MainReactPackage(),
-      } else {
+            new RealmReactPackage()
-        super.onBackPressed();
+        );
-      }
-    }
-
-    @Override
-    public void invokeDefaultOnBackPressed() {
-      super.onBackPressed();
-    }
-
-    @Override
-    protected void onPause() {
-        super.onPause();
-
-        if (mReactInstanceManager != null) {
-            mReactInstanceManager.onPause();
-        }
-    }
-
-    @Override
-    protected void onResume() {
-        super.onResume();
-
-        if (mReactInstanceManager != null) {
-            mReactInstanceManager.onResume(this, this);
-        }
     }
 }

tests/react-test-app/android/app/src/main/java/MainActivity.java

@@ -1,84 +1,45 @@
 package io.realm.react.testapp;
 
-import android.app.Activity;
+import com.facebook.react.ReactActivity;
-import android.os.Bundle;
-import android.view.KeyEvent;
-
-import com.facebook.react.LifecycleState;
-import com.facebook.react.ReactInstanceManager;
 import com.facebook.react.ReactPackage;
-import com.facebook.react.ReactRootView;
-import com.facebook.react.bridge.ReactApplicationContext;
-import com.facebook.react.modules.core.DefaultHardwareBackBtnHandler;
 import com.facebook.react.shell.MainReactPackage;
-import com.rnfs.RNFSPackage;
 
+import java.util.Arrays;
+import java.util.List;
+
+import com.rnfs.RNFSPackage;
 import io.realm.react.RealmReactPackage;
 
-public class MainActivity extends Activity implements DefaultHardwareBackBtnHandler {
+public class MainActivity extends ReactActivity {
-
-    private ReactInstanceManager mReactInstanceManager;
-    private ReactRootView mReactRootView;
 
+    /**
+     * Returns the name of the main component registered from JavaScript.
+     * This is used to schedule rendering of the component.
+     */
     @Override
-    protected void onCreate(Bundle savedInstanceState) {
+    protected String getMainComponentName() {
-        super.onCreate(savedInstanceState);
+        return "ReactTests";
-        mReactRootView = new ReactRootView(this);
-
-        mReactInstanceManager = ReactInstanceManager.builder()
-                .setApplication(getApplication())
-                .setBundleAssetName("index.android.bundle")
-                .setJSMainModuleName("index.android")
-                .addPackage(new MainReactPackage())
-                .addPackage(new RNFSPackage())
-                .addPackage(new RealmReactPackage())
-                .setUseDeveloperSupport(BuildConfig.DEBUG)
-                .setInitialLifecycleState(LifecycleState.RESUMED)
-                .build();
-
-        mReactRootView.startReactApplication(mReactInstanceManager, "ReactTests", null);
-
-        setContentView(mReactRootView);
     }
 
+    /**
+     * Returns whether dev mode should be enabled.
+     * This enables e.g. the dev menu.
+     */
     @Override
-    public boolean onKeyUp(int keyCode, KeyEvent event) {
+    protected boolean getUseDeveloperSupport() {
-        if (keyCode == KeyEvent.KEYCODE_MENU && mReactInstanceManager != null) {
+        return BuildConfig.DEBUG;
-            mReactInstanceManager.showDevOptionsDialog();
-            return true;
-        }
-        return super.onKeyUp(keyCode, event);
     }
 
+    /**
+     * A list of packages used by the app. If the app uses additional views
+     * or modules besides the default ones, add more packages here.
+     */
     @Override
-    public void onBackPressed() {
+    protected List<ReactPackage> getPackages() {
-      if (mReactInstanceManager != null) {
+        return Arrays.<ReactPackage>asList(
-        mReactInstanceManager.onBackPressed();
+            new MainReactPackage(),
-      } else {
+            new RNFSPackage(),
-        super.onBackPressed();
+            new RealmReactPackage()
-      }
+        );
-    }
-
-    @Override
-    public void invokeDefaultOnBackPressed() {
-      super.onBackPressed();
-    }
-
-    @Override
-    protected void onPause() {
-        super.onPause();
-
-        if (mReactInstanceManager != null) {
-            mReactInstanceManager.onPause();
-        }
-    }
-
-    @Override
-    protected void onResume() {
-        super.onResume();
-
-        if (mReactInstanceManager != null) {
-            mReactInstanceManager.onResume(this, this);
-        }
     }
 }