Android AppState

Summary: Closes https://github.com/facebook/react-native/pull/5152

Reviewed By: svcscm

Differential Revision: D2850250

Pulled By: mkonicek

fb-gh-sync-id: 0b5063fa7121d4e304a70da8573c9ba1d05a757c

ReactAndroid/src/main/java/com/facebook/react/modules/appstate/AppStateModule.java

@@ -0,0 +1,76 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+package com.facebook.react.modules.appstate;
+
+import com.facebook.react.bridge.Arguments;
+import com.facebook.react.bridge.Callback;
+import com.facebook.react.bridge.LifecycleEventListener;
+import com.facebook.react.bridge.ReactApplicationContext;
+import com.facebook.react.bridge.ReactContextBaseJavaModule;
+import com.facebook.react.bridge.ReactMethod;
+import com.facebook.react.bridge.WritableMap;
+import com.facebook.react.modules.core.DeviceEventManagerModule.RCTDeviceEventEmitter;
+
+public class AppStateModule extends ReactContextBaseJavaModule
+        implements LifecycleEventListener {
+
+  public static final String APP_STATE_ACTIVE = "active";
+  public static final String APP_STATE_BACKGROUND = "background";
+
+  private String mAppState = "uninitialized";
+
+  public AppStateModule(ReactApplicationContext reactContext) {
+    super(reactContext);
+  }
+
+  @Override
+  public String getName() {
+    return "AppState";
+  }
+
+  @Override
+  public void initialize() {
+    getReactApplicationContext().addLifecycleEventListener(this);
+  }
+
+  @ReactMethod
+  public void getCurrentAppState(Callback success, Callback error) {
+    success.invoke(createAppStateEventMap());
+  }
+
+  @Override
+  public void onHostResume() {
+    mAppState = APP_STATE_ACTIVE;
+    sendAppStateChangeEvent();
+  }
+
+  @Override
+  public void onHostPause() {
+    mAppState = APP_STATE_BACKGROUND;
+    sendAppStateChangeEvent();
+  }
+
+  @Override
+  public void onHostDestroy() {
+    // do not set state to destroyed, do not send an event. By the current implementation, the
+    // catalyst instance is going to be immediately dropped, and all JS calls with it.
+  }
+
+  private WritableMap createAppStateEventMap() {
+    WritableMap appState = Arguments.createMap();
+    appState.putString("app_state", mAppState);
+    return appState;
+  }
+
+  private void sendAppStateChangeEvent() {
+    getReactApplicationContext().getJSModule(RCTDeviceEventEmitter.class)
+            .emit("appStateDidChange", createAppStateEventMap());
+  }
+}

ReactAndroid/src/main/java/com/facebook/react/shell/MainReactPackage.java

@@ -26,6 +26,7 @@ import com.facebook.react.modules.netinfo.NetInfoModule;
 import com.facebook.react.modules.network.NetworkingModule;
 import com.facebook.react.modules.storage.AsyncStorageModule;
 import com.facebook.react.modules.toast.ToastModule;
+import com.facebook.react.modules.appstate.AppStateModule;
 import com.facebook.react.modules.websocket.WebSocketModule;
 import com.facebook.react.uimanager.ViewManager;
 import com.facebook.react.views.art.ARTRenderableViewManager;
@@ -59,6 +60,7 @@ public class MainReactPackage implements ReactPackage {
   @Override
   public List<NativeModule> createNativeModules(ReactApplicationContext reactContext) {
     return Arrays.<NativeModule>asList(
+      new AppStateModule(reactContext),
       new AsyncStorageModule(reactContext),
       new CameraRollManager(reactContext),
       new ClipboardModule(reactContext),
@@ -68,8 +70,8 @@ public class MainReactPackage implements ReactPackage {
       new LocationModule(reactContext),
       new NetworkingModule(reactContext),
       new NetInfoModule(reactContext),
-      new WebSocketModule(reactContext),
-      new ToastModule(reactContext));
+      new ToastModule(reactContext),
+      new WebSocketModule(reactContext));
   }
 
   @Override
@@ -91,17 +93,17 @@ public class MainReactPackage implements ReactPackage {
       new ReactImageManager(),
       new ReactProgressBarViewManager(),
       new ReactRawTextManager(),
-      new RecyclerViewBackedScrollViewManager(),
       new ReactScrollViewManager(),
       new ReactSwitchManager(),
+      new ReactTextInlineImageViewManager(),
       new ReactTextInputManager(),
       new ReactTextViewManager(),
       new ReactToolbarManager(),
       new ReactViewManager(),
       new ReactViewPagerManager(),
-      new ReactTextInlineImageViewManager(),
       new ReactVirtualTextViewManager(),
-      new SwipeRefreshLayoutManager(),
-      new ReactWebViewManager());
+      new ReactWebViewManager(),
+      new RecyclerViewBackedScrollViewManager(),
+      new SwipeRefreshLayoutManager());
   }
 }