Android volume change event (#7)

* Adds volume change event in Android

* Updates podspec and ios module with correct name

* Adds getVolume method to README

* Use correct package name in README example

* Update event Type

Author: rtmalone

README.md

@@ -46,18 +46,25 @@ This component only exposes an api to update device volume and listens for `Volu
 
 import VolumeControl, {
   VolumeControlEvents
-} from "react-native-volume-controller";
+} from "react-native-volume-control";
 import Slider from '@react-native-community/slider';
 
 class App extends React.Component {
+  state = {
+    volume: 0
+  }
 
-    componentDidMount() {
-      // Add and store event listener
-      this.volEvent = VolumeControlEvents.addListener(
-        "VolumeChanged",
-        this.volumeEvent
-      );
-    }
+  async componentDidMount() {
+    this.setState({
+      volume: await VolumeControl.getVolume()
+    });
+
+    // Add and store event listener
+    this.volEvent = VolumeControlEvents.addListener(
+      "VolumeChanged",
+      this.volumeEvent
+    );
+  }
 
   // Updates Slider UI when hardware buttons change volume
   volumeEvent = event => {

RNVolumeController.podspec

@@ -3,10 +3,10 @@ require 'json'
 package = JSON.parse(File.read(File.join(__dir__, 'package.json')))
 
 Pod::Spec.new do |s|
-  s.name                = "RNVolumeController"
+  s.name                = "RNVolumeControl"
   s.version             = package['version']
   s.summary             = package['description']
-  s.homepage            = "https://github.com/tlenclos/react-native-volume-controller"
+  s.homepage            = "https://github.com/rtmalone/react-native-volume-control"
   s.license             = package['license']
   s.author              = package['author']
   s.source              = { :git => package['repository']['url'], :tag => "v#{s.version}" }
@@ -16,6 +16,6 @@ Pod::Spec.new do |s|
   s.preserve_paths      = "**/*.js"
 
   s.subspec 'Main' do |ss|
-    ss.source_files     = "ios/ReactNativeVolumeController.{h,m}"
+    ss.source_files     = "ios/RNVolumeControl.{h,m}"
   end
 end

android/src/main/java/com/rtmalone/volumecontrol/RNVolumeControlModule.java

@@ -1,11 +1,18 @@
 package com.rtmalone.volumecontrol;
 
+import android.app.Activity;
 import android.content.Context;
+import android.content.Intent;
+import android.content.BroadcastReceiver;
+import android.content.IntentFilter;
+import android.media.AudioManager;
+
 import android.support.annotation.Nullable;
 import android.util.Log;
-import android.media.AudioManager;
 
+import com.facebook.react.bridge.ActivityEventListener;
 import com.facebook.react.bridge.Arguments;
+import com.facebook.react.bridge.LifecycleEventListener;
 import com.facebook.react.bridge.ReactApplicationContext;
 import com.facebook.react.bridge.ReactContext;
 import com.facebook.react.bridge.ReactContextBaseJavaModule;
@@ -14,39 +21,79 @@
 import com.facebook.react.bridge.Promise;
 import com.facebook.react.modules.core.DeviceEventManagerModule;
 
-public class RNVolumeControlModule extends ReactContextBaseJavaModule {
+public class RNVolumeControlModule extends ReactContextBaseJavaModule
+    implements ActivityEventListener, LifecycleEventListener {
 
-  private ReactApplicationContext context;
+  private String TAG = RNVolumeControlModule.class.getSimpleName();
+  private ReactApplicationContext rContext;
   private float max_volume = (float) 0.0;
   private AudioManager am;
+  private VolumeBroadcastReceiver volumeBR;
 
   public RNVolumeControlModule(ReactApplicationContext reactContext) {
     super(reactContext);
-    this.context = reactContext;
+    this.rContext = reactContext;
   }
 
   @Override
   public String getName() {
     return "VolumeControl";
   }
 
+  @Override
+  public void onNewIntent(Intent intent) {
+  }
+
+  @Override
+  public void onActivityResult(Activity activity, int requestCode, int resultCode, Intent data) {
+  }
+
+  @Override
+  public void onHostResume() {
+    registerVolumeReceiver();
+  }
+
+  @Override
+  public void onHostPause() {
+    unregisterVolumeReceiver();
+  }
+
+  @Override
+  public void onHostDestroy() {
+  }
+
   @Override
   public void initialize() {
     super.initialize();
 
     try {
-      am = (AudioManager) this.context.getSystemService(Context.AUDIO_SERVICE);
+      am = (AudioManager) this.rContext.getSystemService(Context.AUDIO_SERVICE);
       max_volume = am.getStreamMaxVolume(AudioManager.STREAM_MUSIC);
+      volumeBR = new VolumeBroadcastReceiver();
+      registerVolumeReceiver();
     } catch (Exception e) {
-      Log.e("ERROR", e.getMessage());
+      Log.e(TAG, "Initialize Error", e);
     }
   }
 
-  // public void sendEvent(ReactContext reactContext, String eventName, @Nullable
-  // WritableMap params) {
-  // this.context.getJSModule(DeviceEventManagerModule.RCTDeviceEventEmitter.class).emit(eventName,
-  // params);
-  // }
+  private void registerVolumeReceiver() {
+    if (!volumeBR.isRegistered()) {
+      IntentFilter filter = new IntentFilter("android.media.VOLUME_CHANGED_ACTION");
+      this.rContext.registerReceiver(volumeBR, filter);
+      volumeBR.setRegistered(true);
+    }
+  }
+
+  private void unregisterVolumeReceiver() {
+    if (volumeBR.isRegistered()) {
+      this.rContext.unregisterReceiver(volumeBR);
+      volumeBR.setRegistered(false);
+    }
+  }
+
+  public void sendEvent(ReactContext reactContext, String eventName, @Nullable WritableMap params) {
+    this.rContext.getJSModule(DeviceEventManagerModule.RCTDeviceEventEmitter.class).emit(eventName, params);
+  }
 
   @ReactMethod
   public void getVolume(Promise promise) {
@@ -55,10 +102,44 @@ public void getVolume(Promise promise) {
 
   @ReactMethod
   public void change(float volume) {
-    am.setStreamVolume(AudioManager.STREAM_MUSIC, (int) (volume * max_volume), 0);
+    unregisterVolumeReceiver();
+    try {
+      am.setStreamVolume(AudioManager.STREAM_MUSIC, (int) (volume * max_volume), 0);
+    } catch (Exception e) {
+      Log.e(TAG, "Error Setting Volume", e);
+    }
+    registerVolumeReceiver();
   }
 
   private float getNormalizedVolume() {
-    return am.getStreamVolume(AudioManager.STREAM_MUSIC) * 1.0f / am.getStreamMaxVolume(AudioManager.STREAM_MUSIC);
+    return am.getStreamVolume(AudioManager.STREAM_MUSIC) * 1.0f / max_volume;
+  }
+
+  public class VolumeBroadcastReceiver extends BroadcastReceiver {
+
+    private boolean isRegistered = false;
+
+    public void setRegistered(boolean registered) {
+      isRegistered = registered;
+    }
+
+    public boolean isRegistered() {
+      return isRegistered;
+    }
+
+    @Override
+    public void onReceive(Context context, Intent intent) {
+      if (intent.getAction().equals("android.media.VOLUME_CHANGED_ACTION")) {
+        float volume = getNormalizedVolume();
+        WritableMap params = Arguments.createMap();
+        params.putDouble("volume", volume);
+        try {
+          sendEvent(rContext, "VolumeChanged", params);
+        } catch (RuntimeException e) {
+          // Possible to interact with volume before JS bundle execution is finished.
+          // This is here to avoid app crashing.
+        }
+      }
+    }
   }
 }

index.d.ts

@@ -11,5 +11,5 @@ declare namespace RNVolumeControl {
     volume: number;
   };
 
-  export class RNVCEvents extends NativeEventEmitter {}
+  export class VolumeControlEvents extends NativeEventEmitter {}
 }

ios/RNVolumeControl/RNVolumeControl.m

@@ -18,7 +18,7 @@ @implementation RNVolumeControl {
     bool hasListeners;
 }
 
-RCT_EXPORT_MODULE()
+RCT_EXPORT_MODULE(VolumeControl)
 
 - (NSArray<NSString *> *)supportedEvents
 {